Revision 4f988f152ee087831ea5c1c77cda4454cacc052c authored by Linus Torvalds on 04 May 2012, 22:13:54 UTC, committed by Linus Torvalds on 04 May 2012, 22:13:54 UTC
The normal read_seqcount_begin() function will wait for any current
writers to exit their critical region by looping until the sequence
count is even.

That "wait for sequence count to stabilize" is the right thing to do if
the read-locker will just retry the whole operation on contention: no
point in doing a potentially expensive reader sequence if we know at the
beginning that we'll just end up re-doing it all.

HOWEVER.  Some users don't actually retry the operation, but instead
will abort and do the operation with proper locking.  So the sequence
count case may be the optimistic quick case, but in the presense of
writers you may want to do full locking in order to guarantee forward
progress.  The prime example of this would be the RCU name lookup.

And in that case, you may well be better off without the "retry early",
and are in a rush to instead get to the failure handling.  Thus this
"raw" interface that just returns the sequence number without testing it
- it just forces the low bit to zero so that read_seqcount_retry() will
always fail such a "active concurrent writer" scenario.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent 2f62427
Raw File
seed.c
/*
 * Cryptographic API.
 *
 * SEED Cipher Algorithm.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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_list		=	LIST_HEAD_INIT(seed_alg.cra_list),
	.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);
}

module_init(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>");
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