// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Cryptographic API.
 *
 * SEED Cipher Algorithm.
 *
 * Documentation of SEED can be found in RFC 4269.
 * Copyright (C) 2007 Korea Information Security Agency (KISA).
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/crypto.h>
#include <asm/byteorder.h>

#define SEED_NUM_KCONSTANTS	16
#define SEED_KEY_SIZE		16
#define SEED_BLOCK_SIZE		16
#define SEED_KEYSCHED_LEN	32

/*
 * #define byte(x, nr) ((unsigned char)((x) >> (nr*8)))
 */
static inline u8
byte(const u32 x, const unsigned n)
{
	return x >> (n << 3);
}

struct seed_ctx {
	u32 keysched[SEED_KEYSCHED_LEN];
};

static const u32 SS0[256] = {
	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,
};

static const u32 SS1[256] = {
	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,
};

static const u32 SS2[256] = {
	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,
};

static const u32 SS3[256] = {
	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,
};

static const u32 KC[SEED_NUM_KCONSTANTS] = {
	0x9e3779b9, 0x3c6ef373, 0x78dde6e6, 0xf1bbcdcc,
	0xe3779b99, 0xc6ef3733, 0x8dde6e67, 0x1bbcdccf,
	0x3779b99e, 0x6ef3733c, 0xdde6e678, 0xbbcdccf1,
	0x779b99e3, 0xef3733c6, 0xde6e678d, 0xbcdccf1b,
};

#define OP(X1, X2, X3, X4, rbase)			\
	t0 = X3 ^ ks[rbase];				\
	t1 = X4 ^ ks[rbase+1];				\
	t1 ^= t0;					\
	t1 = SS0[byte(t1, 0)] ^ SS1[byte(t1, 1)] ^	\
		SS2[byte(t1, 2)] ^ SS3[byte(t1, 3)];	\
	t0 += t1;					\
	t0 = SS0[byte(t0, 0)] ^ SS1[byte(t0, 1)] ^	\
		SS2[byte(t0, 2)] ^ SS3[byte(t0, 3)];	\
	t1 += t0;					\
	t1 = SS0[byte(t1, 0)] ^ SS1[byte(t1, 1)] ^	\
		SS2[byte(t1, 2)] ^ SS3[byte(t1, 3)];	\
	t0 += t1;					\
	X1 ^= t0;					\
	X2 ^= t1;

static int seed_set_key(struct crypto_tfm *tfm, const u8 *in_key,
		        unsigned int key_len)
{
	struct seed_ctx *ctx = crypto_tfm_ctx(tfm);
	u32 *keyout = ctx->keysched;
	const __be32 *key = (const __be32 *)in_key;
	u32 i, t0, t1, x1, x2, x3, x4;

	x1 = be32_to_cpu(key[0]);
	x2 = be32_to_cpu(key[1]);
	x3 = be32_to_cpu(key[2]);
	x4 = be32_to_cpu(key[3]);

	for (i = 0; i < SEED_NUM_KCONSTANTS; i++) {
		t0 = x1 + x3 - KC[i];
		t1 = x2 + KC[i] - x4;
		*(keyout++) = SS0[byte(t0, 0)] ^ SS1[byte(t0, 1)] ^
				SS2[byte(t0, 2)] ^ SS3[byte(t0, 3)];
		*(keyout++) = SS0[byte(t1, 0)] ^ SS1[byte(t1, 1)] ^
				SS2[byte(t1, 2)] ^ SS3[byte(t1, 3)];

		if (i % 2 == 0) {
			t0 = x1;
			x1 = (x1 >> 8) ^ (x2 << 24);
			x2 = (x2 >> 8) ^ (t0 << 24);
		} else {
			t0 = x3;
			x3 = (x3 << 8) ^ (x4 >> 24);
			x4 = (x4 << 8) ^ (t0 >> 24);
		}
	}

	return 0;
}

/* encrypt a block of text */

static void seed_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
{
	const struct seed_ctx *ctx = crypto_tfm_ctx(tfm);
	const __be32 *src = (const __be32 *)in;
	__be32 *dst = (__be32 *)out;
	u32 x1, x2, x3, x4, t0, t1;
	const u32 *ks = ctx->keysched;

	x1 = be32_to_cpu(src[0]);
	x2 = be32_to_cpu(src[1]);
	x3 = be32_to_cpu(src[2]);
	x4 = be32_to_cpu(src[3]);

	OP(x1, x2, x3, x4, 0);
	OP(x3, x4, x1, x2, 2);
	OP(x1, x2, x3, x4, 4);
	OP(x3, x4, x1, x2, 6);
	OP(x1, x2, x3, x4, 8);
	OP(x3, x4, x1, x2, 10);
	OP(x1, x2, x3, x4, 12);
	OP(x3, x4, x1, x2, 14);
	OP(x1, x2, x3, x4, 16);
	OP(x3, x4, x1, x2, 18);
	OP(x1, x2, x3, x4, 20);
	OP(x3, x4, x1, x2, 22);
	OP(x1, x2, x3, x4, 24);
	OP(x3, x4, x1, x2, 26);
	OP(x1, x2, x3, x4, 28);
	OP(x3, x4, x1, x2, 30);

	dst[0] = cpu_to_be32(x3);
	dst[1] = cpu_to_be32(x4);
	dst[2] = cpu_to_be32(x1);
	dst[3] = cpu_to_be32(x2);
}

/* decrypt a block of text */

static void seed_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
{
	const struct seed_ctx *ctx = crypto_tfm_ctx(tfm);
	const __be32 *src = (const __be32 *)in;
	__be32 *dst = (__be32 *)out;
	u32 x1, x2, x3, x4, t0, t1;
	const u32 *ks = ctx->keysched;

	x1 = be32_to_cpu(src[0]);
	x2 = be32_to_cpu(src[1]);
	x3 = be32_to_cpu(src[2]);
	x4 = be32_to_cpu(src[3]);

	OP(x1, x2, x3, x4, 30);
	OP(x3, x4, x1, x2, 28);
	OP(x1, x2, x3, x4, 26);
	OP(x3, x4, x1, x2, 24);
	OP(x1, x2, x3, x4, 22);
	OP(x3, x4, x1, x2, 20);
	OP(x1, x2, x3, x4, 18);
	OP(x3, x4, x1, x2, 16);
	OP(x1, x2, x3, x4, 14);
	OP(x3, x4, x1, x2, 12);
	OP(x1, x2, x3, x4, 10);
	OP(x3, x4, x1, x2, 8);
	OP(x1, x2, x3, x4, 6);
	OP(x3, x4, x1, x2, 4);
	OP(x1, x2, x3, x4, 2);
	OP(x3, x4, x1, x2, 0);

	dst[0] = cpu_to_be32(x3);
	dst[1] = cpu_to_be32(x4);
	dst[2] = cpu_to_be32(x1);
	dst[3] = cpu_to_be32(x2);
}


static struct crypto_alg seed_alg = {
	.cra_name		=	"seed",
	.cra_driver_name	=	"seed-generic",
	.cra_priority		=	100,
	.cra_flags		=	CRYPTO_ALG_TYPE_CIPHER,
	.cra_blocksize		=	SEED_BLOCK_SIZE,
	.cra_ctxsize		=	sizeof(struct seed_ctx),
	.cra_alignmask		=	3,
	.cra_module		=	THIS_MODULE,
	.cra_u			=	{
		.cipher = {
			.cia_min_keysize	=	SEED_KEY_SIZE,
			.cia_max_keysize	=	SEED_KEY_SIZE,
			.cia_setkey		=	seed_set_key,
			.cia_encrypt		=	seed_encrypt,
			.cia_decrypt		=	seed_decrypt
		}
	}
};

static int __init seed_init(void)
{
	return crypto_register_alg(&seed_alg);
}

static void __exit seed_fini(void)
{
	crypto_unregister_alg(&seed_alg);
}

subsys_initcall(seed_init);
module_exit(seed_fini);

MODULE_DESCRIPTION("SEED Cipher Algorithm");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Hye-Shik Chang <perky@FreeBSD.org>, Kim Hyun <hkim@kisa.or.kr>");
MODULE_ALIAS_CRYPTO("seed");