// SEED.cs // SPDX-License-Identifier: GPL-3.0-or-later // SPDX-FileCopyrightText: 2025 Catswords OSS and WelsonJS Contributors // https://github.com/gnh1201/welsonjs // // SEED(ISO/IEC 18033-3) cryptography algorithm implementation (Experimental) // using System; namespace WelsonJS.Cryptography { public class SEED { public enum ENDIAN { BIG, LITTLE }; private static ENDIAN DEFAULT_ENDIAN = ENDIAN.BIG; // Constants for Key schedule private const uint KC0 = 0x9e3779b9; private const uint KC1 = 0x3c6ef373; private const uint KC2 = 0x78dde6e6; private const uint KC3 = 0xf1bbcdcc; private const uint KC4 = 0xe3779b99; private const uint KC5 = 0xc6ef3733; private const uint KC6 = 0x8dde6e67; private const uint KC7 = 0x1bbcdccf; private const uint KC8 = 0x3779b99e; private const uint KC9 = 0x6ef3733c; private const uint KC10 = 0xdde6e678; private const uint KC11 = 0xbbcdccf1; private const uint KC12 = 0x779b99e3; private const uint KC13 = 0xef3733c6; private const uint KC14 = 0xde6e678d; private const uint KC15 = 0xbcdccf1b; private const int ABCD_A = 0; private const int ABCD_B = 1; private const int ABCD_C = 2; private const int ABCD_D = 3; private const int LR_L0 = 0; private const int LR_L1 = 1; private const int LR_R0 = 2; private const int LR_R1 = 3; private const int BLOCK_SIZE_SEED = 16; private const int BLOCK_SIZE_SEED_INT = 4; // S-BOX private static readonly uint[] SS0 = new uint[] { 0x2989a1a8, 0x05858184, 0x16c6d2d4, 0x13c3d3d0, 0x14445054, 0x1d0d111c, 0x2c8ca0ac, 0x25052124, 0x1d4d515c, 0x03434340, 0x18081018, 0x1e0e121c, 0x11415150, 0x3cccf0fc, 0x0acac2c8, 0x23436360, 0x28082028, 0x04444044, 0x20002020, 0x1d8d919c, 0x20c0e0e0, 0x22c2e2e0, 0x08c8c0c8, 0x17071314, 0x2585a1a4, 0x0f8f838c, 0x03030300, 0x3b4b7378, 0x3b8bb3b8, 0x13031310, 0x12c2d2d0, 0x2ecee2ec, 0x30407070, 0x0c8c808c, 0x3f0f333c, 0x2888a0a8, 0x32023230, 0x1dcdd1dc, 0x36c6f2f4, 0x34447074, 0x2ccce0ec, 0x15859194, 0x0b0b0308, 0x17475354, 0x1c4c505c, 0x1b4b5358, 0x3d8db1bc, 0x01010100, 0x24042024, 0x1c0c101c, 0x33437370, 0x18889098, 0x10001010, 0x0cccc0cc, 0x32c2f2f0, 0x19c9d1d8, 0x2c0c202c, 0x27c7e3e4, 0x32427270, 0x03838380, 0x1b8b9398, 0x11c1d1d0, 0x06868284, 0x09c9c1c8, 0x20406060, 0x10405050, 0x2383a3a0, 0x2bcbe3e8, 0x0d0d010c, 0x3686b2b4, 0x1e8e929c, 0x0f4f434c, 0x3787b3b4, 0x1a4a5258, 0x06c6c2c4, 0x38487078, 0x2686a2a4, 0x12021210, 0x2f8fa3ac, 0x15c5d1d4, 0x21416160, 0x03c3c3c0, 0x3484b0b4, 0x01414140, 0x12425250, 0x3d4d717c, 0x0d8d818c, 0x08080008, 0x1f0f131c, 0x19899198, 0x00000000, 0x19091118, 0x04040004, 0x13435350, 0x37c7f3f4, 0x21c1e1e0, 0x3dcdf1fc, 0x36467274, 0x2f0f232c, 0x27072324, 0x3080b0b0, 0x0b8b8388, 0x0e0e020c, 0x2b8ba3a8, 0x2282a2a0, 0x2e4e626c, 0x13839390, 0x0d4d414c, 0x29496168, 0x3c4c707c, 0x09090108, 0x0a0a0208, 0x3f8fb3bc, 0x2fcfe3ec, 0x33c3f3f0, 0x05c5c1c4, 0x07878384, 0x14041014, 0x3ecef2fc, 0x24446064, 0x1eced2dc, 0x2e0e222c, 0x0b4b4348, 0x1a0a1218, 0x06060204, 0x21012120, 0x2b4b6368, 0x26466264, 0x02020200, 0x35c5f1f4, 0x12829290, 0x0a8a8288, 0x0c0c000c, 0x3383b3b0, 0x3e4e727c, 0x10c0d0d0, 0x3a4a7278, 0x07474344, 0x16869294, 0x25c5e1e4, 0x26062224, 0x00808080, 0x2d8da1ac, 0x1fcfd3dc, 0x2181a1a0, 0x30003030, 0x37073334, 0x2e8ea2ac, 0x36063234, 0x15051114, 0x22022220, 0x38083038, 0x34c4f0f4, 0x2787a3a4, 0x05454144, 0x0c4c404c, 0x01818180, 0x29c9e1e8, 0x04848084, 0x17879394, 0x35053134, 0x0bcbc3c8, 0x0ecec2cc, 0x3c0c303c, 0x31417170, 0x11011110, 0x07c7c3c4, 0x09898188, 0x35457174, 0x3bcbf3f8, 0x1acad2d8, 0x38c8f0f8, 0x14849094, 0x19495158, 0x02828280, 0x04c4c0c4, 0x3fcff3fc, 0x09494148, 0x39093138, 0x27476364, 0x00c0c0c0, 0x0fcfc3cc, 0x17c7d3d4, 0x3888b0b8, 0x0f0f030c, 0x0e8e828c, 0x02424240, 0x23032320, 0x11819190, 0x2c4c606c, 0x1bcbd3d8, 0x2484a0a4, 0x34043034, 0x31c1f1f0, 0x08484048, 0x02c2c2c0, 0x2f4f636c, 0x3d0d313c, 0x2d0d212c, 0x00404040, 0x3e8eb2bc, 0x3e0e323c, 0x3c8cb0bc, 0x01c1c1c0, 0x2a8aa2a8, 0x3a8ab2b8, 0x0e4e424c, 0x15455154, 0x3b0b3338, 0x1cccd0dc, 0x28486068, 0x3f4f737c, 0x1c8c909c, 0x18c8d0d8, 0x0a4a4248, 0x16465254, 0x37477374, 0x2080a0a0, 0x2dcde1ec, 0x06464244, 0x3585b1b4, 0x2b0b2328, 0x25456164, 0x3acaf2f8, 0x23c3e3e0, 0x3989b1b8, 0x3181b1b0, 0x1f8f939c, 0x1e4e525c, 0x39c9f1f8, 0x26c6e2e4, 0x3282b2b0, 0x31013130, 0x2acae2e8, 0x2d4d616c, 0x1f4f535c, 0x24c4e0e4, 0x30c0f0f0, 0x0dcdc1cc, 0x08888088, 0x16061214, 0x3a0a3238, 0x18485058, 0x14c4d0d4, 0x22426260, 0x29092128, 0x07070304, 0x33033330, 0x28c8e0e8, 0x1b0b1318, 0x05050104, 0x39497178, 0x10809090, 0x2a4a6268, 0x2a0a2228, 0x1a8a9298 }; private static readonly uint[] SS1 = new uint[] { 0x38380830, 0xe828c8e0, 0x2c2d0d21, 0xa42686a2, 0xcc0fcfc3, 0xdc1eced2, 0xb03383b3, 0xb83888b0, 0xac2f8fa3, 0x60204060, 0x54154551, 0xc407c7c3, 0x44044440, 0x6c2f4f63, 0x682b4b63, 0x581b4b53, 0xc003c3c3, 0x60224262, 0x30330333, 0xb43585b1, 0x28290921, 0xa02080a0, 0xe022c2e2, 0xa42787a3, 0xd013c3d3, 0x90118191, 0x10110111, 0x04060602, 0x1c1c0c10, 0xbc3c8cb0, 0x34360632, 0x480b4b43, 0xec2fcfe3, 0x88088880, 0x6c2c4c60, 0xa82888a0, 0x14170713, 0xc404c4c0, 0x14160612, 0xf434c4f0, 0xc002c2c2, 0x44054541, 0xe021c1e1, 0xd416c6d2, 0x3c3f0f33, 0x3c3d0d31, 0x8c0e8e82, 0x98188890, 0x28280820, 0x4c0e4e42, 0xf436c6f2, 0x3c3e0e32, 0xa42585a1, 0xf839c9f1, 0x0c0d0d01, 0xdc1fcfd3, 0xd818c8d0, 0x282b0b23, 0x64264662, 0x783a4a72, 0x24270723, 0x2c2f0f23, 0xf031c1f1, 0x70324272, 0x40024242, 0xd414c4d0, 0x40014141, 0xc000c0c0, 0x70334373, 0x64274763, 0xac2c8ca0, 0x880b8b83, 0xf437c7f3, 0xac2d8da1, 0x80008080, 0x1c1f0f13, 0xc80acac2, 0x2c2c0c20, 0xa82a8aa2, 0x34340430, 0xd012c2d2, 0x080b0b03, 0xec2ecee2, 0xe829c9e1, 0x5c1d4d51, 0x94148490, 0x18180810, 0xf838c8f0, 0x54174753, 0xac2e8ea2, 0x08080800, 0xc405c5c1, 0x10130313, 0xcc0dcdc1, 0x84068682, 0xb83989b1, 0xfc3fcff3, 0x7c3d4d71, 0xc001c1c1, 0x30310131, 0xf435c5f1, 0x880a8a82, 0x682a4a62, 0xb03181b1, 0xd011c1d1, 0x20200020, 0xd417c7d3, 0x00020202, 0x20220222, 0x04040400, 0x68284860, 0x70314171, 0x04070703, 0xd81bcbd3, 0x9c1d8d91, 0x98198991, 0x60214161, 0xbc3e8eb2, 0xe426c6e2, 0x58194951, 0xdc1dcdd1, 0x50114151, 0x90108090, 0xdc1cccd0, 0x981a8a92, 0xa02383a3, 0xa82b8ba3, 0xd010c0d0, 0x80018181, 0x0c0f0f03, 0x44074743, 0x181a0a12, 0xe023c3e3, 0xec2ccce0, 0x8c0d8d81, 0xbc3f8fb3, 0x94168692, 0x783b4b73, 0x5c1c4c50, 0xa02282a2, 0xa02181a1, 0x60234363, 0x20230323, 0x4c0d4d41, 0xc808c8c0, 0x9c1e8e92, 0x9c1c8c90, 0x383a0a32, 0x0c0c0c00, 0x2c2e0e22, 0xb83a8ab2, 0x6c2e4e62, 0x9c1f8f93, 0x581a4a52, 0xf032c2f2, 0x90128292, 0xf033c3f3, 0x48094941, 0x78384870, 0xcc0cccc0, 0x14150511, 0xf83bcbf3, 0x70304070, 0x74354571, 0x7c3f4f73, 0x34350531, 0x10100010, 0x00030303, 0x64244460, 0x6c2d4d61, 0xc406c6c2, 0x74344470, 0xd415c5d1, 0xb43484b0, 0xe82acae2, 0x08090901, 0x74364672, 0x18190911, 0xfc3ecef2, 0x40004040, 0x10120212, 0xe020c0e0, 0xbc3d8db1, 0x04050501, 0xf83acaf2, 0x00010101, 0xf030c0f0, 0x282a0a22, 0x5c1e4e52, 0xa82989a1, 0x54164652, 0x40034343, 0x84058581, 0x14140410, 0x88098981, 0x981b8b93, 0xb03080b0, 0xe425c5e1, 0x48084840, 0x78394971, 0x94178793, 0xfc3cccf0, 0x1c1e0e12, 0x80028282, 0x20210121, 0x8c0c8c80, 0x181b0b13, 0x5c1f4f53, 0x74374773, 0x54144450, 0xb03282b2, 0x1c1d0d11, 0x24250521, 0x4c0f4f43, 0x00000000, 0x44064642, 0xec2dcde1, 0x58184850, 0x50124252, 0xe82bcbe3, 0x7c3e4e72, 0xd81acad2, 0xc809c9c1, 0xfc3dcdf1, 0x30300030, 0x94158591, 0x64254561, 0x3c3c0c30, 0xb43686b2, 0xe424c4e0, 0xb83b8bb3, 0x7c3c4c70, 0x0c0e0e02, 0x50104050, 0x38390931, 0x24260622, 0x30320232, 0x84048480, 0x68294961, 0x90138393, 0x34370733, 0xe427c7e3, 0x24240420, 0xa42484a0, 0xc80bcbc3, 0x50134353, 0x080a0a02, 0x84078783, 0xd819c9d1, 0x4c0c4c40, 0x80038383, 0x8c0f8f83, 0xcc0ecec2, 0x383b0b33, 0x480a4a42, 0xb43787b3 }; private static readonly uint[] SS2 = new uint[] { 0xa1a82989, 0x81840585, 0xd2d416c6, 0xd3d013c3, 0x50541444, 0x111c1d0d, 0xa0ac2c8c, 0x21242505, 0x515c1d4d, 0x43400343, 0x10181808, 0x121c1e0e, 0x51501141, 0xf0fc3ccc, 0xc2c80aca, 0x63602343, 0x20282808, 0x40440444, 0x20202000, 0x919c1d8d, 0xe0e020c0, 0xe2e022c2, 0xc0c808c8, 0x13141707, 0xa1a42585, 0x838c0f8f, 0x03000303, 0x73783b4b, 0xb3b83b8b, 0x13101303, 0xd2d012c2, 0xe2ec2ece, 0x70703040, 0x808c0c8c, 0x333c3f0f, 0xa0a82888, 0x32303202, 0xd1dc1dcd, 0xf2f436c6, 0x70743444, 0xe0ec2ccc, 0x91941585, 0x03080b0b, 0x53541747, 0x505c1c4c, 0x53581b4b, 0xb1bc3d8d, 0x01000101, 0x20242404, 0x101c1c0c, 0x73703343, 0x90981888, 0x10101000, 0xc0cc0ccc, 0xf2f032c2, 0xd1d819c9, 0x202c2c0c, 0xe3e427c7, 0x72703242, 0x83800383, 0x93981b8b, 0xd1d011c1, 0x82840686, 0xc1c809c9, 0x60602040, 0x50501040, 0xa3a02383, 0xe3e82bcb, 0x010c0d0d, 0xb2b43686, 0x929c1e8e, 0x434c0f4f, 0xb3b43787, 0x52581a4a, 0xc2c406c6, 0x70783848, 0xa2a42686, 0x12101202, 0xa3ac2f8f, 0xd1d415c5, 0x61602141, 0xc3c003c3, 0xb0b43484, 0x41400141, 0x52501242, 0x717c3d4d, 0x818c0d8d, 0x00080808, 0x131c1f0f, 0x91981989, 0x00000000, 0x11181909, 0x00040404, 0x53501343, 0xf3f437c7, 0xe1e021c1, 0xf1fc3dcd, 0x72743646, 0x232c2f0f, 0x23242707, 0xb0b03080, 0x83880b8b, 0x020c0e0e, 0xa3a82b8b, 0xa2a02282, 0x626c2e4e, 0x93901383, 0x414c0d4d, 0x61682949, 0x707c3c4c, 0x01080909, 0x02080a0a, 0xb3bc3f8f, 0xe3ec2fcf, 0xf3f033c3, 0xc1c405c5, 0x83840787, 0x10141404, 0xf2fc3ece, 0x60642444, 0xd2dc1ece, 0x222c2e0e, 0x43480b4b, 0x12181a0a, 0x02040606, 0x21202101, 0x63682b4b, 0x62642646, 0x02000202, 0xf1f435c5, 0x92901282, 0x82880a8a, 0x000c0c0c, 0xb3b03383, 0x727c3e4e, 0xd0d010c0, 0x72783a4a, 0x43440747, 0x92941686, 0xe1e425c5, 0x22242606, 0x80800080, 0xa1ac2d8d, 0xd3dc1fcf, 0xa1a02181, 0x30303000, 0x33343707, 0xa2ac2e8e, 0x32343606, 0x11141505, 0x22202202, 0x30383808, 0xf0f434c4, 0xa3a42787, 0x41440545, 0x404c0c4c, 0x81800181, 0xe1e829c9, 0x80840484, 0x93941787, 0x31343505, 0xc3c80bcb, 0xc2cc0ece, 0x303c3c0c, 0x71703141, 0x11101101, 0xc3c407c7, 0x81880989, 0x71743545, 0xf3f83bcb, 0xd2d81aca, 0xf0f838c8, 0x90941484, 0x51581949, 0x82800282, 0xc0c404c4, 0xf3fc3fcf, 0x41480949, 0x31383909, 0x63642747, 0xc0c000c0, 0xc3cc0fcf, 0xd3d417c7, 0xb0b83888, 0x030c0f0f, 0x828c0e8e, 0x42400242, 0x23202303, 0x91901181, 0x606c2c4c, 0xd3d81bcb, 0xa0a42484, 0x30343404, 0xf1f031c1, 0x40480848, 0xc2c002c2, 0x636c2f4f, 0x313c3d0d, 0x212c2d0d, 0x40400040, 0xb2bc3e8e, 0x323c3e0e, 0xb0bc3c8c, 0xc1c001c1, 0xa2a82a8a, 0xb2b83a8a, 0x424c0e4e, 0x51541545, 0x33383b0b, 0xd0dc1ccc, 0x60682848, 0x737c3f4f, 0x909c1c8c, 0xd0d818c8, 0x42480a4a, 0x52541646, 0x73743747, 0xa0a02080, 0xe1ec2dcd, 0x42440646, 0xb1b43585, 0x23282b0b, 0x61642545, 0xf2f83aca, 0xe3e023c3, 0xb1b83989, 0xb1b03181, 0x939c1f8f, 0x525c1e4e, 0xf1f839c9, 0xe2e426c6, 0xb2b03282, 0x31303101, 0xe2e82aca, 0x616c2d4d, 0x535c1f4f, 0xe0e424c4, 0xf0f030c0, 0xc1cc0dcd, 0x80880888, 0x12141606, 0x32383a0a, 0x50581848, 0xd0d414c4, 0x62602242, 0x21282909, 0x03040707, 0x33303303, 0xe0e828c8, 0x13181b0b, 0x01040505, 0x71783949, 0x90901080, 0x62682a4a, 0x22282a0a, 0x92981a8a }; private static uint[] SS3 = new uint[] { 0x08303838, 0xc8e0e828, 0x0d212c2d, 0x86a2a426, 0xcfc3cc0f, 0xced2dc1e, 0x83b3b033, 0x88b0b838, 0x8fa3ac2f, 0x40606020, 0x45515415, 0xc7c3c407, 0x44404404, 0x4f636c2f, 0x4b63682b, 0x4b53581b, 0xc3c3c003, 0x42626022, 0x03333033, 0x85b1b435, 0x09212829, 0x80a0a020, 0xc2e2e022, 0x87a3a427, 0xc3d3d013, 0x81919011, 0x01111011, 0x06020406, 0x0c101c1c, 0x8cb0bc3c, 0x06323436, 0x4b43480b, 0xcfe3ec2f, 0x88808808, 0x4c606c2c, 0x88a0a828, 0x07131417, 0xc4c0c404, 0x06121416, 0xc4f0f434, 0xc2c2c002, 0x45414405, 0xc1e1e021, 0xc6d2d416, 0x0f333c3f, 0x0d313c3d, 0x8e828c0e, 0x88909818, 0x08202828, 0x4e424c0e, 0xc6f2f436, 0x0e323c3e, 0x85a1a425, 0xc9f1f839, 0x0d010c0d, 0xcfd3dc1f, 0xc8d0d818, 0x0b23282b, 0x46626426, 0x4a72783a, 0x07232427, 0x0f232c2f, 0xc1f1f031, 0x42727032, 0x42424002, 0xc4d0d414, 0x41414001, 0xc0c0c000, 0x43737033, 0x47636427, 0x8ca0ac2c, 0x8b83880b, 0xc7f3f437, 0x8da1ac2d, 0x80808000, 0x0f131c1f, 0xcac2c80a, 0x0c202c2c, 0x8aa2a82a, 0x04303434, 0xc2d2d012, 0x0b03080b, 0xcee2ec2e, 0xc9e1e829, 0x4d515c1d, 0x84909414, 0x08101818, 0xc8f0f838, 0x47535417, 0x8ea2ac2e, 0x08000808, 0xc5c1c405, 0x03131013, 0xcdc1cc0d, 0x86828406, 0x89b1b839, 0xcff3fc3f, 0x4d717c3d, 0xc1c1c001, 0x01313031, 0xc5f1f435, 0x8a82880a, 0x4a62682a, 0x81b1b031, 0xc1d1d011, 0x00202020, 0xc7d3d417, 0x02020002, 0x02222022, 0x04000404, 0x48606828, 0x41717031, 0x07030407, 0xcbd3d81b, 0x8d919c1d, 0x89919819, 0x41616021, 0x8eb2bc3e, 0xc6e2e426, 0x49515819, 0xcdd1dc1d, 0x41515011, 0x80909010, 0xccd0dc1c, 0x8a92981a, 0x83a3a023, 0x8ba3a82b, 0xc0d0d010, 0x81818001, 0x0f030c0f, 0x47434407, 0x0a12181a, 0xc3e3e023, 0xcce0ec2c, 0x8d818c0d, 0x8fb3bc3f, 0x86929416, 0x4b73783b, 0x4c505c1c, 0x82a2a022, 0x81a1a021, 0x43636023, 0x03232023, 0x4d414c0d, 0xc8c0c808, 0x8e929c1e, 0x8c909c1c, 0x0a32383a, 0x0c000c0c, 0x0e222c2e, 0x8ab2b83a, 0x4e626c2e, 0x8f939c1f, 0x4a52581a, 0xc2f2f032, 0x82929012, 0xc3f3f033, 0x49414809, 0x48707838, 0xccc0cc0c, 0x05111415, 0xcbf3f83b, 0x40707030, 0x45717435, 0x4f737c3f, 0x05313435, 0x00101010, 0x03030003, 0x44606424, 0x4d616c2d, 0xc6c2c406, 0x44707434, 0xc5d1d415, 0x84b0b434, 0xcae2e82a, 0x09010809, 0x46727436, 0x09111819, 0xcef2fc3e, 0x40404000, 0x02121012, 0xc0e0e020, 0x8db1bc3d, 0x05010405, 0xcaf2f83a, 0x01010001, 0xc0f0f030, 0x0a22282a, 0x4e525c1e, 0x89a1a829, 0x46525416, 0x43434003, 0x85818405, 0x04101414, 0x89818809, 0x8b93981b, 0x80b0b030, 0xc5e1e425, 0x48404808, 0x49717839, 0x87939417, 0xccf0fc3c, 0x0e121c1e, 0x82828002, 0x01212021, 0x8c808c0c, 0x0b13181b, 0x4f535c1f, 0x47737437, 0x44505414, 0x82b2b032, 0x0d111c1d, 0x05212425, 0x4f434c0f, 0x00000000, 0x46424406, 0xcde1ec2d, 0x48505818, 0x42525012, 0xcbe3e82b, 0x4e727c3e, 0xcad2d81a, 0xc9c1c809, 0xcdf1fc3d, 0x00303030, 0x85919415, 0x45616425, 0x0c303c3c, 0x86b2b436, 0xc4e0e424, 0x8bb3b83b, 0x4c707c3c, 0x0e020c0e, 0x40505010, 0x09313839, 0x06222426, 0x02323032, 0x84808404, 0x49616829, 0x83939013, 0x07333437, 0xc7e3e427, 0x04202424, 0x84a0a424, 0xcbc3c80b, 0x43535013, 0x0a02080a, 0x87838407, 0xc9d1d819, 0x4c404c0c, 0x83838003, 0x8f838c0f, 0xcec2cc0e, 0x0b33383b, 0x4a42480a, 0x87b3b437 }; private static uint GetUIntFromByteArray(byte[] src, int srcOffset, ENDIAN endian = ENDIAN.BIG) { if (src == null || src.Length < srcOffset + 4) throw new ArgumentException("Invalid source array or offset."); return (uint)(endian == ENDIAN.BIG ? (src[srcOffset] & 0xFF) << 24 | (src[srcOffset + 1] & 0xFF) << 16 | (src[srcOffset + 2] & 0xFF) << 8 | (src[srcOffset + 3] & 0xFF) : (src[srcOffset] & 0xFF) | (src[srcOffset + 1] & 0xFF) << 8 | (src[srcOffset + 2] & 0xFF) << 16 | (src[srcOffset + 3] & 0xFF) << 24); } private static byte GetByteFromUInt(uint value, int position) { if (position < 0 || position >= 4) throw new ArgumentException("Position must be between 0 and 3."); return position > 0 ? (byte)((value >> (8 * position)) & 0xFF) : (byte)(value & 0xFF); } public static void SetByteToUIntArray(ref uint[] dst, int byteOffset, byte value, ENDIAN endian) { if (dst == null || byteOffset < 0 || byteOffset >= dst.Length * 4) throw new ArgumentOutOfRangeException(nameof(byteOffset), "Invalid byte offset."); int uintIndex = byteOffset / 4; int shiftValue = (endian == ENDIAN.BIG) ? (3 - byteOffset % 4) * 8 : (byteOffset % 4) * 8; uint maskValue = (uint)(0xFF << shiftValue); uint maskValue2 = ~maskValue; uint valueToSet = (uint)(value & 0xFF) << shiftValue; dst[uintIndex] = (dst[uintIndex] & maskValue2) | (valueToSet & maskValue); } public static byte GetByteFromUIntArray(uint[] src, int byteOffset, ENDIAN endian) { if (src == null || byteOffset < 0 || byteOffset >= src.Length * 4) throw new ArgumentOutOfRangeException(nameof(byteOffset), "Invalid byte offset."); int uintIndex = byteOffset / 4; int shiftValue = (endian == ENDIAN.BIG) ? (3 - byteOffset % 4) * 8 : (byteOffset % 4) * 8; return (byte)((src[uintIndex] >> shiftValue) & 0xFF); } private static uint[] ConvertToUIntArray(byte[] src, int inLen, ENDIAN endian = ENDIAN.BIG) { if (src == null) throw new ArgumentNullException(nameof(src), "source cannot be null."); if (inLen <= 0 || inLen > src.Length) throw new ArgumentException("Invalid input length.", nameof(inLen)); int outLen = (inLen + 3) / 4; uint[] data = new uint[outLen]; for (int i = 0; i < outLen; i++) { data[i] = GetUIntFromByteArray(src, i * 4, endian); } return data; } private static byte[] ConvertToByteArray(uint[] src, int inLen, ENDIAN endian = ENDIAN.BIG) { if (src == null) throw new ArgumentNullException(nameof(src), "source cannot be null."); if (inLen <= 0 || inLen > src.Length) throw new ArgumentException("Invalid input length.", nameof(inLen)); int outLen = inLen; byte[] data = new byte[outLen]; for (int i = 0; i < outLen; i++) { data[i] = GetByteFromUIntArray(src, i, endian); } return data; } private static uint Substitute(uint value) { return SS0[GetByteFromUInt(value, 0)] ^ SS1[GetByteFromUInt(value, 1)] ^ SS2[GetByteFromUInt(value, 2)] ^ SS3[GetByteFromUInt(value, 3)]; } // Round function F and adding output of F to L. // L0, L1 : left input values at each round // R0, R1 : right input values at each round // K : round keys at each round private static void SeedRound(ref uint[] T, ref uint[] LR, int L0, int L1, int R0, int R1, uint[] K, int K_offset) { T[0] = LR[R0] ^ K[K_offset + 0]; T[1] = LR[R1] ^ K[K_offset + 1]; T[1] ^= T[0]; T[1] = Substitute(T[1]); T[0] += T[1]; T[0] = Substitute(T[0]); T[1] += T[0]; T[1] = Substitute(T[1]); T[0] += T[1]; LR[L0] ^= T[0]; LR[L1] ^= T[1]; } private static uint EndianChange(uint value) { return ((value & 0x000000FF) << 24) | // Move the first byte to the fourth byte position ((value & 0x0000FF00) << 8) | // Move the second byte to the third byte position ((value & 0x00FF0000) >> 8) | // Move the third byte to the second byte position ((value & 0xFF000000) >> 24); // Move the fourth byte to the first byte position } private static void RoundKeyUpdate0(ref uint[] T, ref uint[] K, int K_offset, ref uint[] ABCD, uint KC) { T[0] = ABCD[ABCD_A] + ABCD[ABCD_C] - KC; T[1] = ABCD[ABCD_B] + KC - ABCD[ABCD_D]; K[K_offset + 0] = Substitute(T[0]); K[K_offset + 1] = Substitute(T[1]); T[0] = ABCD[ABCD_A]; ABCD[ABCD_A] = ((ABCD[ABCD_A] >> 8) & 0x00ffffff) ^ (ABCD[ABCD_B] << 24); ABCD[ABCD_B] = ((ABCD[ABCD_B] >> 8) & 0x00ffffff) ^ (T[0] << 24); } private static void RoundKeyUpdate1(ref uint[] T, ref uint[] K, int K_offset, ref uint[] ABCD, uint KC) { T[0] = ABCD[ABCD_A] + ABCD[ABCD_C] - KC; T[1] = ABCD[ABCD_B] + KC - ABCD[ABCD_D]; K[K_offset + 0] = Substitute(T[0]); K[K_offset + 1] = Substitute(T[1]); T[0] = ABCD[ABCD_C]; ABCD[ABCD_C] = (ABCD[ABCD_C] << 8) ^ ((ABCD[ABCD_D] >> 24) & 0x000000ff); ABCD[ABCD_D] = (ABCD[ABCD_D] << 8) ^ ((T[0] >> 24) & 0x000000ff); } public class ECB { public void EncryptBlock(in uint[] _in, int in_offset, ref uint[] _out, int out_offset, KISA_SEED_KEY ks) { uint[] LR = new uint[4]; // Iuput/output values at each rounds uint[] T = new uint[2]; // Temporary variables for round function F uint[] K = ks.key_data; // Pointer of round keys // Set up input values for first round LR[LR_L0] = _in[in_offset + 0]; LR[LR_L1] = _in[in_offset + 1]; LR[LR_R0] = _in[in_offset + 2]; LR[LR_R1] = _in[in_offset + 3]; // Reorder for big endian // Because SEED use little endian order in default if (ENDIAN.BIG != DEFAULT_ENDIAN) { LR[LR_L0] = EndianChange(LR[LR_L0]); LR[LR_L1] = EndianChange(LR[LR_L1]); LR[LR_R0] = EndianChange(LR[LR_R0]); LR[LR_R1] = EndianChange(LR[LR_R1]); } SeedRound(ref T, ref LR, LR_L0, LR_L1, LR_R0, LR_R1, K, 0); // Round 1 SeedRound(ref T, ref LR, LR_R0, LR_R1, LR_L0, LR_L1, K, 2); // Round 2 SeedRound(ref T, ref LR, LR_L0, LR_L1, LR_R0, LR_R1, K, 4); // Round 3 SeedRound(ref T, ref LR, LR_R0, LR_R1, LR_L0, LR_L1, K, 6); // Round 4 SeedRound(ref T, ref LR, LR_L0, LR_L1, LR_R0, LR_R1, K, 8); // Round 5 SeedRound(ref T, ref LR, LR_R0, LR_R1, LR_L0, LR_L1, K, 10); // Round 6 SeedRound(ref T, ref LR, LR_L0, LR_L1, LR_R0, LR_R1, K, 12); // Round 7 SeedRound(ref T, ref LR, LR_R0, LR_R1, LR_L0, LR_L1, K, 14); // Round 8 SeedRound(ref T, ref LR, LR_L0, LR_L1, LR_R0, LR_R1, K, 16); // Round 9 SeedRound(ref T, ref LR, LR_R0, LR_R1, LR_L0, LR_L1, K, 18); // Round 10 SeedRound(ref T, ref LR, LR_L0, LR_L1, LR_R0, LR_R1, K, 20); // Round 11 SeedRound(ref T, ref LR, LR_R0, LR_R1, LR_L0, LR_L1, K, 22); // Round 12 SeedRound(ref T, ref LR, LR_L0, LR_L1, LR_R0, LR_R1, K, 24); // Round 13 SeedRound(ref T, ref LR, LR_R0, LR_R1, LR_L0, LR_L1, K, 26); // Round 14 SeedRound(ref T, ref LR, LR_L0, LR_L1, LR_R0, LR_R1, K, 28); // Round 15 SeedRound(ref T, ref LR, LR_R0, LR_R1, LR_L0, LR_L1, K, 30); // Round 16 if (ENDIAN.BIG != DEFAULT_ENDIAN) { LR[LR_L0] = EndianChange(LR[LR_L0]); LR[LR_L1] = EndianChange(LR[LR_L1]); LR[LR_R0] = EndianChange(LR[LR_R0]); LR[LR_R1] = EndianChange(LR[LR_R1]); } // Copying output values from last round to pbData _out[out_offset + 0] = LR[LR_R0]; _out[out_offset + 1] = LR[LR_R1]; _out[out_offset + 2] = LR[LR_L0]; _out[out_offset + 3] = LR[LR_L1]; } public void DecryptBlock(in uint[] _in, int in_offset, ref uint[] _out, int out_offset, KISA_SEED_KEY ks) { uint[] LR = new uint[4]; // Iuput/output values at each rounds uint[] T = new uint[2]; // Temporary variables for round function F uint[] K = ks.key_data; // Pointer of round keys // Set up input values for first round LR[LR_L0] = _in[in_offset + 0]; LR[LR_L1] = _in[in_offset + 1]; LR[LR_R0] = _in[in_offset + 2]; LR[LR_R1] = _in[in_offset + 3]; // Reorder for big endian if (ENDIAN.BIG != DEFAULT_ENDIAN) { LR[LR_L0] = EndianChange(LR[LR_L0]); LR[LR_L1] = EndianChange(LR[LR_L1]); LR[LR_R0] = EndianChange(LR[LR_R0]); LR[LR_R1] = EndianChange(LR[LR_R1]); } SeedRound(ref T, ref LR, LR_L0, LR_L1, LR_R0, LR_R1, K, 30); // Round 1 SeedRound(ref T, ref LR, LR_R0, LR_R1, LR_L0, LR_L1, K, 28); // Round 2 SeedRound(ref T, ref LR, LR_L0, LR_L1, LR_R0, LR_R1, K, 26); // Round 3 SeedRound(ref T, ref LR, LR_R0, LR_R1, LR_L0, LR_L1, K, 24); // Round 4 SeedRound(ref T, ref LR, LR_L0, LR_L1, LR_R0, LR_R1, K, 22); // Round 5 SeedRound(ref T, ref LR, LR_R0, LR_R1, LR_L0, LR_L1, K, 20); // Round 6 SeedRound(ref T, ref LR, LR_L0, LR_L1, LR_R0, LR_R1, K, 18); // Round 7 SeedRound(ref T, ref LR, LR_R0, LR_R1, LR_L0, LR_L1, K, 16); // Round 8 SeedRound(ref T, ref LR, LR_L0, LR_L1, LR_R0, LR_R1, K, 14); // Round 9 SeedRound(ref T, ref LR, LR_R0, LR_R1, LR_L0, LR_L1, K, 12); // Round 10 SeedRound(ref T, ref LR, LR_L0, LR_L1, LR_R0, LR_R1, K, 10); // Round 11 SeedRound(ref T, ref LR, LR_R0, LR_R1, LR_L0, LR_L1, K, 8); // Round 12 SeedRound(ref T, ref LR, LR_L0, LR_L1, LR_R0, LR_R1, K, 6); // Round 13 SeedRound(ref T, ref LR, LR_R0, LR_R1, LR_L0, LR_L1, K, 4); // Round 14 SeedRound(ref T, ref LR, LR_L0, LR_L1, LR_R0, LR_R1, K, 2); // Round 15 SeedRound(ref T, ref LR, LR_R0, LR_R1, LR_L0, LR_L1, K, 0); // Round 16 if (ENDIAN.BIG != DEFAULT_ENDIAN) { LR[LR_L0] = EndianChange(LR[LR_L0]); LR[LR_L1] = EndianChange(LR[LR_L1]); LR[LR_R0] = EndianChange(LR[LR_R0]); LR[LR_R1] = EndianChange(LR[LR_R1]); } // Copy output values from last round to pbData _out[out_offset + 0] = LR[LR_R0]; _out[out_offset + 1] = LR[LR_R1]; _out[out_offset + 2] = LR[LR_L0]; _out[out_offset + 3] = LR[LR_L1]; } public void Init(KISA_SEED_INFO pInfo, KISA_ENC_DEC enc, byte[] pbszUserKey) { uint[] ABCD = new uint[4]; // Iuput/output values at each rounds uint[] T = new uint[2]; // Temporary variable uint[] K; if (pInfo == null || pbszUserKey == null) throw new ArgumentException("Invalid arguments"); K = pInfo.seed_key.key_data; // Pointer of round keys pInfo.encrypt = enc.value; pInfo.last_block_flag = pInfo.buffer_length = 0; // Set up input values for Key Schedule ABCD[ABCD_A] = GetUIntFromByteArray(pbszUserKey, 0 * 4, DEFAULT_ENDIAN); ABCD[ABCD_B] = GetUIntFromByteArray(pbszUserKey, 1 * 4, DEFAULT_ENDIAN); ABCD[ABCD_C] = GetUIntFromByteArray(pbszUserKey, 2 * 4, DEFAULT_ENDIAN); ABCD[ABCD_D] = GetUIntFromByteArray(pbszUserKey, 3 * 4, DEFAULT_ENDIAN); // Reorder for big endian if (ENDIAN.BIG != DEFAULT_ENDIAN) { ABCD[ABCD_A] = EndianChange(ABCD[ABCD_A]); ABCD[ABCD_B] = EndianChange(ABCD[ABCD_B]); ABCD[ABCD_C] = EndianChange(ABCD[ABCD_C]); ABCD[ABCD_D] = EndianChange(ABCD[ABCD_D]); } // i-th round keys( K_i,0 and K_i,1 ) are denoted as K[2*(i-1)] and K[2*i-1], respectively RoundKeyUpdate0(ref T, ref K, 0, ref ABCD, KC0); // K_1,0 and K_1,1 RoundKeyUpdate1(ref T, ref K, 2, ref ABCD, KC1); // K_2,0 and K_2,1 RoundKeyUpdate0(ref T, ref K, 4, ref ABCD, KC2); // K_3,0 and K_3,1 RoundKeyUpdate1(ref T, ref K, 6, ref ABCD, KC3); // K_4,0 and K_4,1 RoundKeyUpdate0(ref T, ref K, 8, ref ABCD, KC4); // K_5,0 and K_5,1 RoundKeyUpdate1(ref T, ref K, 10, ref ABCD, KC5); // K_6,0 and K_6,1 RoundKeyUpdate0(ref T, ref K, 12, ref ABCD, KC6); // K_7,0 and K_7,1 RoundKeyUpdate1(ref T, ref K, 14, ref ABCD, KC7); // K_8,0 and K_8,1 RoundKeyUpdate0(ref T, ref K, 16, ref ABCD, KC8); // K_9,0 and K_9,1 RoundKeyUpdate1(ref T, ref K, 18, ref ABCD, KC9); // K_10,0 and K_10,1 RoundKeyUpdate0(ref T, ref K, 20, ref ABCD, KC10); // K_11,0 and K_11,1 RoundKeyUpdate1(ref T, ref K, 22, ref ABCD, KC11); // K_12,0 and K_12,1 RoundKeyUpdate0(ref T, ref K, 24, ref ABCD, KC12); // K_13,0 and K_13,1 RoundKeyUpdate1(ref T, ref K, 26, ref ABCD, KC13); // K_14,0 and K_14,1 RoundKeyUpdate0(ref T, ref K, 28, ref ABCD, KC14); // K_15,0 and K_15,1 T[0] = ABCD[ABCD_A] + ABCD[ABCD_C] - KC15; T[1] = ABCD[ABCD_B] - ABCD[ABCD_D] + KC15; K[30] = SS0[GetByteFromUInt(T[0], 0) & 0x0ff] ^ SS1[GetByteFromUInt(T[0], 1) & 0x0ff] ^ // K_16,0 SS2[GetByteFromUInt(T[0], 2) & 0x0ff] ^ SS3[GetByteFromUInt(T[0], 3) & 0x0ff]; K[31] = SS0[GetByteFromUInt(T[1], 0) & 0x0ff] ^ SS1[GetByteFromUInt(T[1], 1) & 0x0ff] ^ // K_16,1 SS2[GetByteFromUInt(T[1], 2) & 0x0ff] ^ SS3[GetByteFromUInt(T[1], 3) & 0x0ff]; } public void Process(KISA_SEED_INFO pInfo, in uint[] _in, int inLen, ref uint[] _out, ref int[] outLen) { int nCurrentCount = BLOCK_SIZE_SEED; int in_offset = 0; int out_offset = 0; if (pInfo == null || _in == null || _out == null || inLen <= 0) throw new ArgumentException("Invalid arguments."); if (KISA_ENC_DEC._KISA_ENCRYPT == pInfo.encrypt) { while (nCurrentCount <= inLen) { EncryptBlock(_in, in_offset, ref _out, out_offset, pInfo.seed_key); nCurrentCount += BLOCK_SIZE_SEED; in_offset += BLOCK_SIZE_SEED_INT; out_offset += BLOCK_SIZE_SEED_INT; } outLen[0] = nCurrentCount - BLOCK_SIZE_SEED; pInfo.buffer_length = inLen - outLen[0]; Array.Copy(_in, in_offset, pInfo.ecb_buffer, 0, pInfo.buffer_length); } else { while (nCurrentCount <= inLen) { DecryptBlock(_in, in_offset, ref _out, out_offset, pInfo.seed_key); nCurrentCount += BLOCK_SIZE_SEED; in_offset += BLOCK_SIZE_SEED_INT; out_offset += BLOCK_SIZE_SEED_INT; } outLen[0] = nCurrentCount - BLOCK_SIZE_SEED; Array.Copy(_out, out_offset - BLOCK_SIZE_SEED_INT, pInfo.ecb_last_block, 0, BLOCK_SIZE_SEED); } } public bool Close(KISA_SEED_INFO pInfo, uint[] _out, int out_offset, ref int[] outLen) { int nPaddngLen; outLen[0] = 0; if (_out == null) return false; if (KISA_ENC_DEC._KISA_ENCRYPT == pInfo.encrypt) { nPaddngLen = BLOCK_SIZE_SEED - pInfo.buffer_length; for (int i = pInfo.buffer_length; i < BLOCK_SIZE_SEED; i++) { SetByteToUIntArray(ref pInfo.ecb_buffer, i, (byte)nPaddngLen, DEFAULT_ENDIAN); } EncryptBlock(pInfo.ecb_buffer, 0, ref _out, (out_offset) / 4, pInfo.seed_key); outLen[0] = BLOCK_SIZE_SEED; } else { nPaddngLen = GetByteFromUIntArray(pInfo.ecb_last_block, BLOCK_SIZE_SEED - 1, DEFAULT_ENDIAN); if (nPaddngLen > 0 && nPaddngLen <= BLOCK_SIZE_SEED) { for (int i = nPaddngLen; i > 0; i--) { SetByteToUIntArray(ref _out, out_offset - i, (byte)0x00, DEFAULT_ENDIAN); } outLen[0] = nPaddngLen; } else { return false; } } return true; } public byte[] Encrypt(byte[] pbszUserKey, byte[] pbData, int offset, int length) { KISA_SEED_INFO info = new KISA_SEED_INFO(); uint[] _out; uint[] data; byte[] cdata; int outLen; int[] nRetOutLen = new int[] { 0 }; int[] nPaddingLen = new int[] { 0 }; byte[] pbszPlainText = new byte[length]; Array.Copy(pbData, offset, pbszPlainText, 0, length); int nPlainTextLen = length; int nPlainTextPadding = (BLOCK_SIZE_SEED - (nPlainTextLen) % BLOCK_SIZE_SEED); byte[] newpbszPlainText = new byte[nPlainTextLen + nPlainTextPadding]; Array.Copy(pbszPlainText, newpbszPlainText, nPlainTextLen); byte[] pbszCipherText = new byte[nPlainTextLen + nPlainTextPadding]; Init(info, KISA_ENC_DEC.KISA_ENCRYPT, pbszUserKey); outLen = ((nPlainTextLen / 16) + 1) * 4; _out = new uint[outLen]; data = ConvertToUIntArray(newpbszPlainText, nPlainTextLen); Process(info, data, nPlainTextLen, ref _out, ref nRetOutLen); Close(info, _out, nRetOutLen[0], ref nPaddingLen); cdata = ConvertToByteArray(_out, nRetOutLen[0] + nPaddingLen[0]); Array.Copy(cdata, pbszCipherText, nRetOutLen[0] + nPaddingLen[0]); data = null; cdata = null; _out = null; return pbszCipherText; } public byte[] Decrypt(byte[] pbszUserKey, byte[] pbData, int offset, int length) { byte[] result = new byte[] { }; KISA_SEED_INFO info = new KISA_SEED_INFO(); uint[] _out; uint[] data; byte[] cdata; int outLen = 0; int[] nRetOutLen = new int[] { 0 }; int[] nPaddingLen = new int[] { 0 }; byte[] pbszCipherText = pbData; int nCipherTextLen = length; if (nCipherTextLen % BLOCK_SIZE_SEED > 0) { return result; } byte[] newpbszCipherText = new byte[nCipherTextLen]; Array.Copy(pbszCipherText, newpbszCipherText, nCipherTextLen); byte[] pbszPlainText = new byte[nCipherTextLen]; Init(info, KISA_ENC_DEC.KISA_DECRYPT, pbszUserKey); outLen = (nCipherTextLen / 16) * 4; _out = new uint[outLen]; data = ConvertToUIntArray(newpbszCipherText, nCipherTextLen); Process(info, data, nCipherTextLen, ref _out, ref nRetOutLen); if (Close(info, _out, nRetOutLen[0], ref nPaddingLen)) { cdata = ConvertToByteArray(_out, nRetOutLen[0] - nPaddingLen[0]); Array.Copy(cdata, pbszPlainText, nRetOutLen[0] - nPaddingLen[0]); int message_length = nRetOutLen[0] - nPaddingLen[0]; if (message_length < 0) { message_length = 0; } result = new byte[message_length]; Array.Copy(pbszPlainText, 0, result, 0, message_length); data = null; cdata = null; _out = null; } return result; } } public static void SetDefaultEndian(ENDIAN endian) { DEFAULT_ENDIAN = endian; } public class KISA_ENC_DEC { public const int _KISA_DECRYPT = 0; public const int _KISA_ENCRYPT = 1; public int value; public KISA_ENC_DEC(int value) { this.value = value; } public static KISA_ENC_DEC KISA_ENCRYPT = new KISA_ENC_DEC(_KISA_ENCRYPT); public static KISA_ENC_DEC KISA_DECRYPT = new KISA_ENC_DEC(_KISA_DECRYPT); } public class KISA_SEED_KEY { public uint[] key_data = new uint[32]; public void Init() { for (int i = 0; i < key_data.Length; i++) { key_data[i] = 0; } } } public class KISA_SEED_INFO { public int encrypt; public KISA_SEED_KEY seed_key = new KISA_SEED_KEY(); public uint[] ecb_buffer = new uint[4]; public int buffer_length; public uint[] ecb_last_block = new uint[4]; public int last_block_flag; public KISA_SEED_INFO() { encrypt = 0; seed_key.Init(); ecb_buffer[0] = ecb_buffer[1] = ecb_buffer[2] = ecb_buffer[3] = 0; buffer_length = 0; ecb_last_block[0] = ecb_last_block[1] = ecb_last_block[2] = ecb_last_block[3] = 0; last_block_flag = 0; } } } } /* References: * [1] KISA(Korea Internet & Security Agency) - SEED * https://seed.kisa.or.kr/kisa/algorithm/EgovSeedInfo.do * [2] ISO - ISO/IEC 18033-3:2010 - Information technology — Security techniques — Encryption algorithms - Part 3: Block ciphers * https://www.iso.org/standard/54531.html * [3] KISA(Korea Internet & Security Agency) - SEED 128 Algorithm Specification * https://ics.catswords.net/SEED%2B128_Specification_english_M.pdf * [4] KISA(Korea Internet & Security Agency) - SEED 128 알고리즘 상세 명세서 * https://ics.catswords.net/SEED_Algorithm_Specification_korean_M.pdf * [5] KISA(Korea Internet & Security Agency) - SEED 블록암호 알고리즘에 대한 소스코드 활용 매뉴얼 * https://ics.catswords.net/SEED_sourcecode_explanation_korean.pdf */