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
cast6.c
/* Kernel cryptographic api.
 * cast6.c - Cast6 cipher algorithm [rfc2612].
 *
 * CAST-256 (*cast6*) is a DES like Substitution-Permutation Network (SPN)
 * cryptosystem built upon the CAST-128 (*cast5*) [rfc2144] encryption
 * algorithm.
 *
 * Copyright (C) 2003 Kartikey Mahendra Bhatt <kartik_me@hotmail.com>.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
 */


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

#define CAST6_BLOCK_SIZE 16
#define CAST6_MIN_KEY_SIZE 16
#define CAST6_MAX_KEY_SIZE 32

struct cast6_ctx {
	u32 Km[12][4];
	u8 Kr[12][4];
};

#define F1(D, r, m)  ((I = ((m) + (D))), (I = rol32(I, (r))),   \
    (((s1[I >> 24] ^ s2[(I>>16)&0xff]) - s3[(I>>8)&0xff]) + s4[I&0xff]))
#define F2(D, r, m)  ((I = ((m) ^ (D))), (I = rol32(I, (r))),   \
    (((s1[I >> 24] - s2[(I>>16)&0xff]) + s3[(I>>8)&0xff]) ^ s4[I&0xff]))
#define F3(D, r, m)  ((I = ((m) - (D))), (I = rol32(I, (r))),   \
    (((s1[I >> 24] + s2[(I>>16)&0xff]) ^ s3[(I>>8)&0xff]) - s4[I&0xff]))

static const u32 s1[256] = {
	0x30fb40d4, 0x9fa0ff0b, 0x6beccd2f, 0x3f258c7a, 0x1e213f2f,
	0x9c004dd3, 0x6003e540, 0xcf9fc949,
	0xbfd4af27, 0x88bbbdb5, 0xe2034090, 0x98d09675, 0x6e63a0e0,
	0x15c361d2, 0xc2e7661d, 0x22d4ff8e,
	0x28683b6f, 0xc07fd059, 0xff2379c8, 0x775f50e2, 0x43c340d3,
	0xdf2f8656, 0x887ca41a, 0xa2d2bd2d,
	0xa1c9e0d6, 0x346c4819, 0x61b76d87, 0x22540f2f, 0x2abe32e1,
	0xaa54166b, 0x22568e3a, 0xa2d341d0,
	0x66db40c8, 0xa784392f, 0x004dff2f, 0x2db9d2de, 0x97943fac,
	0x4a97c1d8, 0x527644b7, 0xb5f437a7,
	0xb82cbaef, 0xd751d159, 0x6ff7f0ed, 0x5a097a1f, 0x827b68d0,
	0x90ecf52e, 0x22b0c054, 0xbc8e5935,
	0x4b6d2f7f, 0x50bb64a2, 0xd2664910, 0xbee5812d, 0xb7332290,
	0xe93b159f, 0xb48ee411, 0x4bff345d,
	0xfd45c240, 0xad31973f, 0xc4f6d02e, 0x55fc8165, 0xd5b1caad,
	0xa1ac2dae, 0xa2d4b76d, 0xc19b0c50,
	0x882240f2, 0x0c6e4f38, 0xa4e4bfd7, 0x4f5ba272, 0x564c1d2f,
	0xc59c5319, 0xb949e354, 0xb04669fe,
	0xb1b6ab8a, 0xc71358dd, 0x6385c545, 0x110f935d, 0x57538ad5,
	0x6a390493, 0xe63d37e0, 0x2a54f6b3,
	0x3a787d5f, 0x6276a0b5, 0x19a6fcdf, 0x7a42206a, 0x29f9d4d5,
	0xf61b1891, 0xbb72275e, 0xaa508167,
	0x38901091, 0xc6b505eb, 0x84c7cb8c, 0x2ad75a0f, 0x874a1427,
	0xa2d1936b, 0x2ad286af, 0xaa56d291,
	0xd7894360, 0x425c750d, 0x93b39e26, 0x187184c9, 0x6c00b32d,
	0x73e2bb14, 0xa0bebc3c, 0x54623779,
	0x64459eab, 0x3f328b82, 0x7718cf82, 0x59a2cea6, 0x04ee002e,
	0x89fe78e6, 0x3fab0950, 0x325ff6c2,
	0x81383f05, 0x6963c5c8, 0x76cb5ad6, 0xd49974c9, 0xca180dcf,
	0x380782d5, 0xc7fa5cf6, 0x8ac31511,
	0x35e79e13, 0x47da91d0, 0xf40f9086, 0xa7e2419e, 0x31366241,
	0x051ef495, 0xaa573b04, 0x4a805d8d,
	0x548300d0, 0x00322a3c, 0xbf64cddf, 0xba57a68e, 0x75c6372b,
	0x50afd341, 0xa7c13275, 0x915a0bf5,
	0x6b54bfab, 0x2b0b1426, 0xab4cc9d7, 0x449ccd82, 0xf7fbf265,
	0xab85c5f3, 0x1b55db94, 0xaad4e324,
	0xcfa4bd3f, 0x2deaa3e2, 0x9e204d02, 0xc8bd25ac, 0xeadf55b3,
	0xd5bd9e98, 0xe31231b2, 0x2ad5ad6c,
	0x954329de, 0xadbe4528, 0xd8710f69, 0xaa51c90f, 0xaa786bf6,
	0x22513f1e, 0xaa51a79b, 0x2ad344cc,
	0x7b5a41f0, 0xd37cfbad, 0x1b069505, 0x41ece491, 0xb4c332e6,
	0x032268d4, 0xc9600acc, 0xce387e6d,
	0xbf6bb16c, 0x6a70fb78, 0x0d03d9c9, 0xd4df39de, 0xe01063da,
	0x4736f464, 0x5ad328d8, 0xb347cc96,
	0x75bb0fc3, 0x98511bfb, 0x4ffbcc35, 0xb58bcf6a, 0xe11f0abc,
	0xbfc5fe4a, 0xa70aec10, 0xac39570a,
	0x3f04442f, 0x6188b153, 0xe0397a2e, 0x5727cb79, 0x9ceb418f,
	0x1cacd68d, 0x2ad37c96, 0x0175cb9d,
	0xc69dff09, 0xc75b65f0, 0xd9db40d8, 0xec0e7779, 0x4744ead4,
	0xb11c3274, 0xdd24cb9e, 0x7e1c54bd,
	0xf01144f9, 0xd2240eb1, 0x9675b3fd, 0xa3ac3755, 0xd47c27af,
	0x51c85f4d, 0x56907596, 0xa5bb15e6,
	0x580304f0, 0xca042cf1, 0x011a37ea, 0x8dbfaadb, 0x35ba3e4a,
	0x3526ffa0, 0xc37b4d09, 0xbc306ed9,
	0x98a52666, 0x5648f725, 0xff5e569d, 0x0ced63d0, 0x7c63b2cf,
	0x700b45e1, 0xd5ea50f1, 0x85a92872,
	0xaf1fbda7, 0xd4234870, 0xa7870bf3, 0x2d3b4d79, 0x42e04198,
	0x0cd0ede7, 0x26470db8, 0xf881814c,
	0x474d6ad7, 0x7c0c5e5c, 0xd1231959, 0x381b7298, 0xf5d2f4db,
	0xab838653, 0x6e2f1e23, 0x83719c9e,
	0xbd91e046, 0x9a56456e, 0xdc39200c, 0x20c8c571, 0x962bda1c,
	0xe1e696ff, 0xb141ab08, 0x7cca89b9,
	0x1a69e783, 0x02cc4843, 0xa2f7c579, 0x429ef47d, 0x427b169c,
	0x5ac9f049, 0xdd8f0f00, 0x5c8165bf
};

static const u32 s2[256] = {
	0x1f201094, 0xef0ba75b, 0x69e3cf7e, 0x393f4380, 0xfe61cf7a,
	0xeec5207a, 0x55889c94, 0x72fc0651,
	0xada7ef79, 0x4e1d7235, 0xd55a63ce, 0xde0436ba, 0x99c430ef,
	0x5f0c0794, 0x18dcdb7d, 0xa1d6eff3,
	0xa0b52f7b, 0x59e83605, 0xee15b094, 0xe9ffd909, 0xdc440086,
	0xef944459, 0xba83ccb3, 0xe0c3cdfb,
	0xd1da4181, 0x3b092ab1, 0xf997f1c1, 0xa5e6cf7b, 0x01420ddb,
	0xe4e7ef5b, 0x25a1ff41, 0xe180f806,
	0x1fc41080, 0x179bee7a, 0xd37ac6a9, 0xfe5830a4, 0x98de8b7f,
	0x77e83f4e, 0x79929269, 0x24fa9f7b,
	0xe113c85b, 0xacc40083, 0xd7503525, 0xf7ea615f, 0x62143154,
	0x0d554b63, 0x5d681121, 0xc866c359,
	0x3d63cf73, 0xcee234c0, 0xd4d87e87, 0x5c672b21, 0x071f6181,
	0x39f7627f, 0x361e3084, 0xe4eb573b,
	0x602f64a4, 0xd63acd9c, 0x1bbc4635, 0x9e81032d, 0x2701f50c,
	0x99847ab4, 0xa0e3df79, 0xba6cf38c,
	0x10843094, 0x2537a95e, 0xf46f6ffe, 0xa1ff3b1f, 0x208cfb6a,
	0x8f458c74, 0xd9e0a227, 0x4ec73a34,
	0xfc884f69, 0x3e4de8df, 0xef0e0088, 0x3559648d, 0x8a45388c,
	0x1d804366, 0x721d9bfd, 0xa58684bb,
	0xe8256333, 0x844e8212, 0x128d8098, 0xfed33fb4, 0xce280ae1,
	0x27e19ba5, 0xd5a6c252, 0xe49754bd,
	0xc5d655dd, 0xeb667064, 0x77840b4d, 0xa1b6a801, 0x84db26a9,
	0xe0b56714, 0x21f043b7, 0xe5d05860,
	0x54f03084, 0x066ff472, 0xa31aa153, 0xdadc4755, 0xb5625dbf,
	0x68561be6, 0x83ca6b94, 0x2d6ed23b,
	0xeccf01db, 0xa6d3d0ba, 0xb6803d5c, 0xaf77a709, 0x33b4a34c,
	0x397bc8d6, 0x5ee22b95, 0x5f0e5304,
	0x81ed6f61, 0x20e74364, 0xb45e1378, 0xde18639b, 0x881ca122,
	0xb96726d1, 0x8049a7e8, 0x22b7da7b,
	0x5e552d25, 0x5272d237, 0x79d2951c, 0xc60d894c, 0x488cb402,
	0x1ba4fe5b, 0xa4b09f6b, 0x1ca815cf,
	0xa20c3005, 0x8871df63, 0xb9de2fcb, 0x0cc6c9e9, 0x0beeff53,
	0xe3214517, 0xb4542835, 0x9f63293c,
	0xee41e729, 0x6e1d2d7c, 0x50045286, 0x1e6685f3, 0xf33401c6,
	0x30a22c95, 0x31a70850, 0x60930f13,
	0x73f98417, 0xa1269859, 0xec645c44, 0x52c877a9, 0xcdff33a6,
	0xa02b1741, 0x7cbad9a2, 0x2180036f,
	0x50d99c08, 0xcb3f4861, 0xc26bd765, 0x64a3f6ab, 0x80342676,
	0x25a75e7b, 0xe4e6d1fc, 0x20c710e6,
	0xcdf0b680, 0x17844d3b, 0x31eef84d, 0x7e0824e4, 0x2ccb49eb,
	0x846a3bae, 0x8ff77888, 0xee5d60f6,
	0x7af75673, 0x2fdd5cdb, 0xa11631c1, 0x30f66f43, 0xb3faec54,
	0x157fd7fa, 0xef8579cc, 0xd152de58,
	0xdb2ffd5e, 0x8f32ce19, 0x306af97a, 0x02f03ef8, 0x99319ad5,
	0xc242fa0f, 0xa7e3ebb0, 0xc68e4906,
	0xb8da230c, 0x80823028, 0xdcdef3c8, 0xd35fb171, 0x088a1bc8,
	0xbec0c560, 0x61a3c9e8, 0xbca8f54d,
	0xc72feffa, 0x22822e99, 0x82c570b4, 0xd8d94e89, 0x8b1c34bc,
	0x301e16e6, 0x273be979, 0xb0ffeaa6,
	0x61d9b8c6, 0x00b24869, 0xb7ffce3f, 0x08dc283b, 0x43daf65a,
	0xf7e19798, 0x7619b72f, 0x8f1c9ba4,
	0xdc8637a0, 0x16a7d3b1, 0x9fc393b7, 0xa7136eeb, 0xc6bcc63e,
	0x1a513742, 0xef6828bc, 0x520365d6,
	0x2d6a77ab, 0x3527ed4b, 0x821fd216, 0x095c6e2e, 0xdb92f2fb,
	0x5eea29cb, 0x145892f5, 0x91584f7f,
	0x5483697b, 0x2667a8cc, 0x85196048, 0x8c4bacea, 0x833860d4,
	0x0d23e0f9, 0x6c387e8a, 0x0ae6d249,
	0xb284600c, 0xd835731d, 0xdcb1c647, 0xac4c56ea, 0x3ebd81b3,
	0x230eabb0, 0x6438bc87, 0xf0b5b1fa,
	0x8f5ea2b3, 0xfc184642, 0x0a036b7a, 0x4fb089bd, 0x649da589,
	0xa345415e, 0x5c038323, 0x3e5d3bb9,
	0x43d79572, 0x7e6dd07c, 0x06dfdf1e, 0x6c6cc4ef, 0x7160a539,
	0x73bfbe70, 0x83877605, 0x4523ecf1
};

static const u32 s3[256] = {
	0x8defc240, 0x25fa5d9f, 0xeb903dbf, 0xe810c907, 0x47607fff,
	0x369fe44b, 0x8c1fc644, 0xaececa90,
	0xbeb1f9bf, 0xeefbcaea, 0xe8cf1950, 0x51df07ae, 0x920e8806,
	0xf0ad0548, 0xe13c8d83, 0x927010d5,
	0x11107d9f, 0x07647db9, 0xb2e3e4d4, 0x3d4f285e, 0xb9afa820,
	0xfade82e0, 0xa067268b, 0x8272792e,
	0x553fb2c0, 0x489ae22b, 0xd4ef9794, 0x125e3fbc, 0x21fffcee,
	0x825b1bfd, 0x9255c5ed, 0x1257a240,
	0x4e1a8302, 0xbae07fff, 0x528246e7, 0x8e57140e, 0x3373f7bf,
	0x8c9f8188, 0xa6fc4ee8, 0xc982b5a5,
	0xa8c01db7, 0x579fc264, 0x67094f31, 0xf2bd3f5f, 0x40fff7c1,
	0x1fb78dfc, 0x8e6bd2c1, 0x437be59b,
	0x99b03dbf, 0xb5dbc64b, 0x638dc0e6, 0x55819d99, 0xa197c81c,
	0x4a012d6e, 0xc5884a28, 0xccc36f71,
	0xb843c213, 0x6c0743f1, 0x8309893c, 0x0feddd5f, 0x2f7fe850,
	0xd7c07f7e, 0x02507fbf, 0x5afb9a04,
	0xa747d2d0, 0x1651192e, 0xaf70bf3e, 0x58c31380, 0x5f98302e,
	0x727cc3c4, 0x0a0fb402, 0x0f7fef82,
	0x8c96fdad, 0x5d2c2aae, 0x8ee99a49, 0x50da88b8, 0x8427f4a0,
	0x1eac5790, 0x796fb449, 0x8252dc15,
	0xefbd7d9b, 0xa672597d, 0xada840d8, 0x45f54504, 0xfa5d7403,
	0xe83ec305, 0x4f91751a, 0x925669c2,
	0x23efe941, 0xa903f12e, 0x60270df2, 0x0276e4b6, 0x94fd6574,
	0x927985b2, 0x8276dbcb, 0x02778176,
	0xf8af918d, 0x4e48f79e, 0x8f616ddf, 0xe29d840e, 0x842f7d83,
	0x340ce5c8, 0x96bbb682, 0x93b4b148,
	0xef303cab, 0x984faf28, 0x779faf9b, 0x92dc560d, 0x224d1e20,
	0x8437aa88, 0x7d29dc96, 0x2756d3dc,
	0x8b907cee, 0xb51fd240, 0xe7c07ce3, 0xe566b4a1, 0xc3e9615e,
	0x3cf8209d, 0x6094d1e3, 0xcd9ca341,
	0x5c76460e, 0x00ea983b, 0xd4d67881, 0xfd47572c, 0xf76cedd9,
	0xbda8229c, 0x127dadaa, 0x438a074e,
	0x1f97c090, 0x081bdb8a, 0x93a07ebe, 0xb938ca15, 0x97b03cff,
	0x3dc2c0f8, 0x8d1ab2ec, 0x64380e51,
	0x68cc7bfb, 0xd90f2788, 0x12490181, 0x5de5ffd4, 0xdd7ef86a,
	0x76a2e214, 0xb9a40368, 0x925d958f,
	0x4b39fffa, 0xba39aee9, 0xa4ffd30b, 0xfaf7933b, 0x6d498623,
	0x193cbcfa, 0x27627545, 0x825cf47a,
	0x61bd8ba0, 0xd11e42d1, 0xcead04f4, 0x127ea392, 0x10428db7,
	0x8272a972, 0x9270c4a8, 0x127de50b,
	0x285ba1c8, 0x3c62f44f, 0x35c0eaa5, 0xe805d231, 0x428929fb,
	0xb4fcdf82, 0x4fb66a53, 0x0e7dc15b,
	0x1f081fab, 0x108618ae, 0xfcfd086d, 0xf9ff2889, 0x694bcc11,
	0x236a5cae, 0x12deca4d, 0x2c3f8cc5,
	0xd2d02dfe, 0xf8ef5896, 0xe4cf52da, 0x95155b67, 0x494a488c,
	0xb9b6a80c, 0x5c8f82bc, 0x89d36b45,
	0x3a609437, 0xec00c9a9, 0x44715253, 0x0a874b49, 0xd773bc40,
	0x7c34671c, 0x02717ef6, 0x4feb5536,
	0xa2d02fff, 0xd2bf60c4, 0xd43f03c0, 0x50b4ef6d, 0x07478cd1,
	0x006e1888, 0xa2e53f55, 0xb9e6d4bc,
	0xa2048016, 0x97573833, 0xd7207d67, 0xde0f8f3d, 0x72f87b33,
	0xabcc4f33, 0x7688c55d, 0x7b00a6b0,
	0x947b0001, 0x570075d2, 0xf9bb88f8, 0x8942019e, 0x4264a5ff,
	0x856302e0, 0x72dbd92b, 0xee971b69,
	0x6ea22fde, 0x5f08ae2b, 0xaf7a616d, 0xe5c98767, 0xcf1febd2,
	0x61efc8c2, 0xf1ac2571, 0xcc8239c2,
	0x67214cb8, 0xb1e583d1, 0xb7dc3e62, 0x7f10bdce, 0xf90a5c38,
	0x0ff0443d, 0x606e6dc6, 0x60543a49,
	0x5727c148, 0x2be98a1d, 0x8ab41738, 0x20e1be24, 0xaf96da0f,
	0x68458425, 0x99833be5, 0x600d457d,
	0x282f9350, 0x8334b362, 0xd91d1120, 0x2b6d8da0, 0x642b1e31,
	0x9c305a00, 0x52bce688, 0x1b03588a,
	0xf7baefd5, 0x4142ed9c, 0xa4315c11, 0x83323ec5, 0xdfef4636,
	0xa133c501, 0xe9d3531c, 0xee353783
};

static const u32 s4[256] = {
	0x9db30420, 0x1fb6e9de, 0xa7be7bef, 0xd273a298, 0x4a4f7bdb,
	0x64ad8c57, 0x85510443, 0xfa020ed1,
	0x7e287aff, 0xe60fb663, 0x095f35a1, 0x79ebf120, 0xfd059d43,
	0x6497b7b1, 0xf3641f63, 0x241e4adf,
	0x28147f5f, 0x4fa2b8cd, 0xc9430040, 0x0cc32220, 0xfdd30b30,
	0xc0a5374f, 0x1d2d00d9, 0x24147b15,
	0xee4d111a, 0x0fca5167, 0x71ff904c, 0x2d195ffe, 0x1a05645f,
	0x0c13fefe, 0x081b08ca, 0x05170121,
	0x80530100, 0xe83e5efe, 0xac9af4f8, 0x7fe72701, 0xd2b8ee5f,
	0x06df4261, 0xbb9e9b8a, 0x7293ea25,
	0xce84ffdf, 0xf5718801, 0x3dd64b04, 0xa26f263b, 0x7ed48400,
	0x547eebe6, 0x446d4ca0, 0x6cf3d6f5,
	0x2649abdf, 0xaea0c7f5, 0x36338cc1, 0x503f7e93, 0xd3772061,
	0x11b638e1, 0x72500e03, 0xf80eb2bb,
	0xabe0502e, 0xec8d77de, 0x57971e81, 0xe14f6746, 0xc9335400,
	0x6920318f, 0x081dbb99, 0xffc304a5,
	0x4d351805, 0x7f3d5ce3, 0xa6c866c6, 0x5d5bcca9, 0xdaec6fea,
	0x9f926f91, 0x9f46222f, 0x3991467d,
	0xa5bf6d8e, 0x1143c44f, 0x43958302, 0xd0214eeb, 0x022083b8,
	0x3fb6180c, 0x18f8931e, 0x281658e6,
	0x26486e3e, 0x8bd78a70, 0x7477e4c1, 0xb506e07c, 0xf32d0a25,
	0x79098b02, 0xe4eabb81, 0x28123b23,
	0x69dead38, 0x1574ca16, 0xdf871b62, 0x211c40b7, 0xa51a9ef9,
	0x0014377b, 0x041e8ac8, 0x09114003,
	0xbd59e4d2, 0xe3d156d5, 0x4fe876d5, 0x2f91a340, 0x557be8de,
	0x00eae4a7, 0x0ce5c2ec, 0x4db4bba6,
	0xe756bdff, 0xdd3369ac, 0xec17b035, 0x06572327, 0x99afc8b0,
	0x56c8c391, 0x6b65811c, 0x5e146119,
	0x6e85cb75, 0xbe07c002, 0xc2325577, 0x893ff4ec, 0x5bbfc92d,
	0xd0ec3b25, 0xb7801ab7, 0x8d6d3b24,
	0x20c763ef, 0xc366a5fc, 0x9c382880, 0x0ace3205, 0xaac9548a,
	0xeca1d7c7, 0x041afa32, 0x1d16625a,
	0x6701902c, 0x9b757a54, 0x31d477f7, 0x9126b031, 0x36cc6fdb,
	0xc70b8b46, 0xd9e66a48, 0x56e55a79,
	0x026a4ceb, 0x52437eff, 0x2f8f76b4, 0x0df980a5, 0x8674cde3,
	0xedda04eb, 0x17a9be04, 0x2c18f4df,
	0xb7747f9d, 0xab2af7b4, 0xefc34d20, 0x2e096b7c, 0x1741a254,
	0xe5b6a035, 0x213d42f6, 0x2c1c7c26,
	0x61c2f50f, 0x6552daf9, 0xd2c231f8, 0x25130f69, 0xd8167fa2,
	0x0418f2c8, 0x001a96a6, 0x0d1526ab,
	0x63315c21, 0x5e0a72ec, 0x49bafefd, 0x187908d9, 0x8d0dbd86,
	0x311170a7, 0x3e9b640c, 0xcc3e10d7,
	0xd5cad3b6, 0x0caec388, 0xf73001e1, 0x6c728aff, 0x71eae2a1,
	0x1f9af36e, 0xcfcbd12f, 0xc1de8417,
	0xac07be6b, 0xcb44a1d8, 0x8b9b0f56, 0x013988c3, 0xb1c52fca,
	0xb4be31cd, 0xd8782806, 0x12a3a4e2,
	0x6f7de532, 0x58fd7eb6, 0xd01ee900, 0x24adffc2, 0xf4990fc5,
	0x9711aac5, 0x001d7b95, 0x82e5e7d2,
	0x109873f6, 0x00613096, 0xc32d9521, 0xada121ff, 0x29908415,
	0x7fbb977f, 0xaf9eb3db, 0x29c9ed2a,
	0x5ce2a465, 0xa730f32c, 0xd0aa3fe8, 0x8a5cc091, 0xd49e2ce7,
	0x0ce454a9, 0xd60acd86, 0x015f1919,
	0x77079103, 0xdea03af6, 0x78a8565e, 0xdee356df, 0x21f05cbe,
	0x8b75e387, 0xb3c50651, 0xb8a5c3ef,
	0xd8eeb6d2, 0xe523be77, 0xc2154529, 0x2f69efdf, 0xafe67afb,
	0xf470c4b2, 0xf3e0eb5b, 0xd6cc9876,
	0x39e4460c, 0x1fda8538, 0x1987832f, 0xca007367, 0xa99144f8,
	0x296b299e, 0x492fc295, 0x9266beab,
	0xb5676e69, 0x9bd3ddda, 0xdf7e052f, 0xdb25701c, 0x1b5e51ee,
	0xf65324e6, 0x6afce36c, 0x0316cc04,
	0x8644213e, 0xb7dc59d0, 0x7965291f, 0xccd6fd43, 0x41823979,
	0x932bcdf6, 0xb657c34d, 0x4edfd282,
	0x7ae5290c, 0x3cb9536b, 0x851e20fe, 0x9833557e, 0x13ecf0b0,
	0xd3ffb372, 0x3f85c5c1, 0x0aef7ed2
};

static const u32 Tm[24][8] = {
	{ 0x5a827999, 0xc95c653a, 0x383650db, 0xa7103c7c, 0x15ea281d,
		0x84c413be, 0xf39dff5f, 0x6277eb00 } ,
	{ 0xd151d6a1, 0x402bc242, 0xaf05ade3, 0x1ddf9984, 0x8cb98525,
		0xfb9370c6, 0x6a6d5c67, 0xd9474808 } ,
	{ 0x482133a9, 0xb6fb1f4a, 0x25d50aeb, 0x94aef68c, 0x0388e22d,
		0x7262cdce, 0xe13cb96f, 0x5016a510 } ,
	{ 0xbef090b1, 0x2dca7c52, 0x9ca467f3, 0x0b7e5394, 0x7a583f35,
		0xe9322ad6, 0x580c1677, 0xc6e60218 } ,
	{ 0x35bfedb9, 0xa499d95a, 0x1373c4fb, 0x824db09c, 0xf1279c3d,
		0x600187de, 0xcedb737f, 0x3db55f20 } ,
	{ 0xac8f4ac1, 0x1b693662, 0x8a432203, 0xf91d0da4, 0x67f6f945,
		0xd6d0e4e6, 0x45aad087, 0xb484bc28 } ,
	{ 0x235ea7c9, 0x9238936a, 0x01127f0b, 0x6fec6aac, 0xdec6564d,
		0x4da041ee, 0xbc7a2d8f, 0x2b541930 } ,
	{ 0x9a2e04d1, 0x0907f072, 0x77e1dc13, 0xe6bbc7b4, 0x5595b355,
		0xc46f9ef6, 0x33498a97, 0xa2237638 } ,
	{ 0x10fd61d9, 0x7fd74d7a, 0xeeb1391b, 0x5d8b24bc, 0xcc65105d,
		0x3b3efbfe, 0xaa18e79f, 0x18f2d340 } ,
	{ 0x87ccbee1, 0xf6a6aa82, 0x65809623, 0xd45a81c4, 0x43346d65,
		0xb20e5906, 0x20e844a7, 0x8fc23048 } ,
	{ 0xfe9c1be9, 0x6d76078a, 0xdc4ff32b, 0x4b29decc, 0xba03ca6d,
		0x28ddb60e, 0x97b7a1af, 0x06918d50 } ,
	{ 0x756b78f1, 0xe4456492, 0x531f5033, 0xc1f93bd4, 0x30d32775,
		0x9fad1316, 0x0e86feb7, 0x7d60ea58 } ,
	{ 0xec3ad5f9, 0x5b14c19a, 0xc9eead3b, 0x38c898dc, 0xa7a2847d,
		0x167c701e, 0x85565bbf, 0xf4304760 } ,
	{ 0x630a3301, 0xd1e41ea2, 0x40be0a43, 0xaf97f5e4, 0x1e71e185,
		0x8d4bcd26, 0xfc25b8c7, 0x6affa468 } ,
	{ 0xd9d99009, 0x48b37baa, 0xb78d674b, 0x266752ec, 0x95413e8d,
		0x041b2a2e, 0x72f515cf, 0xe1cf0170 } ,
	{ 0x50a8ed11, 0xbf82d8b2, 0x2e5cc453, 0x9d36aff4, 0x0c109b95,
		0x7aea8736, 0xe9c472d7, 0x589e5e78 } ,
	{ 0xc7784a19, 0x365235ba, 0xa52c215b, 0x14060cfc, 0x82dff89d,
		0xf1b9e43e, 0x6093cfdf, 0xcf6dbb80 } ,
	{ 0x3e47a721, 0xad2192c2, 0x1bfb7e63, 0x8ad56a04, 0xf9af55a5,
		0x68894146, 0xd7632ce7, 0x463d1888 } ,
	{ 0xb5170429, 0x23f0efca, 0x92cadb6b, 0x01a4c70c, 0x707eb2ad,
		0xdf589e4e, 0x4e3289ef, 0xbd0c7590 } ,
	{ 0x2be66131, 0x9ac04cd2, 0x099a3873, 0x78742414, 0xe74e0fb5,
		0x5627fb56, 0xc501e6f7, 0x33dbd298 } ,
	{ 0xa2b5be39, 0x118fa9da, 0x8069957b, 0xef43811c, 0x5e1d6cbd,
		0xccf7585e, 0x3bd143ff, 0xaaab2fa0 } ,
	{ 0x19851b41, 0x885f06e2, 0xf738f283, 0x6612de24, 0xd4ecc9c5,
		0x43c6b566, 0xb2a0a107, 0x217a8ca8 } ,
	{ 0x90547849, 0xff2e63ea, 0x6e084f8b, 0xdce23b2c, 0x4bbc26cd,
		0xba96126e, 0x296ffe0f, 0x9849e9b0 } ,
	{ 0x0723d551, 0x75fdc0f2, 0xe4d7ac93, 0x53b19834, 0xc28b83d5,
		0x31656f76, 0xa03f5b17, 0x0f1946b8 }
};

static const u8 Tr[4][8] = {
	{ 0x13, 0x04, 0x15, 0x06, 0x17, 0x08, 0x19, 0x0a } ,
	{ 0x1b, 0x0c, 0x1d, 0x0e, 0x1f, 0x10, 0x01, 0x12 } ,
	{ 0x03, 0x14, 0x05, 0x16, 0x07, 0x18, 0x09, 0x1a } ,
	{ 0x0b, 0x1c, 0x0d, 0x1e, 0x0f, 0x00, 0x11, 0x02 }
};

/* forward octave */
static void W(u32 *key, unsigned int i)
{
	u32 I;
	key[6] ^= F1(key[7], Tr[i % 4][0], Tm[i][0]);
	key[5] ^= F2(key[6], Tr[i % 4][1], Tm[i][1]);
	key[4] ^= F3(key[5], Tr[i % 4][2], Tm[i][2]);
	key[3] ^= F1(key[4], Tr[i % 4][3], Tm[i][3]);
	key[2] ^= F2(key[3], Tr[i % 4][4], Tm[i][4]);
	key[1] ^= F3(key[2], Tr[i % 4][5], Tm[i][5]);
	key[0] ^= F1(key[1], Tr[i % 4][6], Tm[i][6]);
	key[7] ^= F2(key[0], Tr[i % 4][7], Tm[i][7]);
}

static int cast6_setkey(struct crypto_tfm *tfm, const u8 *in_key,
			unsigned key_len)
{
	int i;
	u32 key[8];
	__be32 p_key[8]; /* padded key */
	struct cast6_ctx *c = crypto_tfm_ctx(tfm);
	u32 *flags = &tfm->crt_flags;

	if (key_len % 4 != 0) {
		*flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
		return -EINVAL;
	}

	memset(p_key, 0, 32);
	memcpy(p_key, in_key, key_len);

	key[0] = be32_to_cpu(p_key[0]);		/* A */
	key[1] = be32_to_cpu(p_key[1]);		/* B */
	key[2] = be32_to_cpu(p_key[2]);		/* C */
	key[3] = be32_to_cpu(p_key[3]);		/* D */
	key[4] = be32_to_cpu(p_key[4]);		/* E */
	key[5] = be32_to_cpu(p_key[5]);		/* F */
	key[6] = be32_to_cpu(p_key[6]);		/* G */
	key[7] = be32_to_cpu(p_key[7]);		/* H */

	for (i = 0; i < 12; i++) {
		W(key, 2 * i);
		W(key, 2 * i + 1);

		c->Kr[i][0] = key[0] & 0x1f;
		c->Kr[i][1] = key[2] & 0x1f;
		c->Kr[i][2] = key[4] & 0x1f;
		c->Kr[i][3] = key[6] & 0x1f;

		c->Km[i][0] = key[7];
		c->Km[i][1] = key[5];
		c->Km[i][2] = key[3];
		c->Km[i][3] = key[1];
	}

	return 0;
}

/*forward quad round*/
static void Q(u32 *block, u8 *Kr, u32 *Km)
{
	u32 I;
	block[2] ^= F1(block[3], Kr[0], Km[0]);
	block[1] ^= F2(block[2], Kr[1], Km[1]);
	block[0] ^= F3(block[1], Kr[2], Km[2]);
	block[3] ^= F1(block[0], Kr[3], Km[3]);
}

/*reverse quad round*/
static void QBAR(u32 *block, u8 *Kr, u32 *Km)
{
	u32 I;
	block[3] ^= F1(block[0], Kr[3], Km[3]);
	block[0] ^= F3(block[1], Kr[2], Km[2]);
	block[1] ^= F2(block[2], Kr[1], Km[1]);
	block[2] ^= F1(block[3], Kr[0], Km[0]);
}

static void cast6_encrypt(struct crypto_tfm *tfm, u8 *outbuf, const u8 *inbuf)
{
	struct cast6_ctx *c = crypto_tfm_ctx(tfm);
	const __be32 *src = (const __be32 *)inbuf;
	__be32 *dst = (__be32 *)outbuf;
	u32 block[4];
	u32 *Km;
	u8 *Kr;

	block[0] = be32_to_cpu(src[0]);
	block[1] = be32_to_cpu(src[1]);
	block[2] = be32_to_cpu(src[2]);
	block[3] = be32_to_cpu(src[3]);

	Km = c->Km[0]; Kr = c->Kr[0]; Q(block, Kr, Km);
	Km = c->Km[1]; Kr = c->Kr[1]; Q(block, Kr, Km);
	Km = c->Km[2]; Kr = c->Kr[2]; Q(block, Kr, Km);
	Km = c->Km[3]; Kr = c->Kr[3]; Q(block, Kr, Km);
	Km = c->Km[4]; Kr = c->Kr[4]; Q(block, Kr, Km);
	Km = c->Km[5]; Kr = c->Kr[5]; Q(block, Kr, Km);
	Km = c->Km[6]; Kr = c->Kr[6]; QBAR(block, Kr, Km);
	Km = c->Km[7]; Kr = c->Kr[7]; QBAR(block, Kr, Km);
	Km = c->Km[8]; Kr = c->Kr[8]; QBAR(block, Kr, Km);
	Km = c->Km[9]; Kr = c->Kr[9]; QBAR(block, Kr, Km);
	Km = c->Km[10]; Kr = c->Kr[10]; QBAR(block, Kr, Km);
	Km = c->Km[11]; Kr = c->Kr[11]; QBAR(block, Kr, Km);

	dst[0] = cpu_to_be32(block[0]);
	dst[1] = cpu_to_be32(block[1]);
	dst[2] = cpu_to_be32(block[2]);
	dst[3] = cpu_to_be32(block[3]);
}

static void cast6_decrypt(struct crypto_tfm *tfm, u8 *outbuf, const u8 *inbuf)
{
	struct cast6_ctx *c = crypto_tfm_ctx(tfm);
	const __be32 *src = (const __be32 *)inbuf;
	__be32 *dst = (__be32 *)outbuf;
	u32 block[4];
	u32 *Km;
	u8 *Kr;

	block[0] = be32_to_cpu(src[0]);
	block[1] = be32_to_cpu(src[1]);
	block[2] = be32_to_cpu(src[2]);
	block[3] = be32_to_cpu(src[3]);

	Km = c->Km[11]; Kr = c->Kr[11]; Q(block, Kr, Km);
	Km = c->Km[10]; Kr = c->Kr[10]; Q(block, Kr, Km);
	Km = c->Km[9]; Kr = c->Kr[9]; Q(block, Kr, Km);
	Km = c->Km[8]; Kr = c->Kr[8]; Q(block, Kr, Km);
	Km = c->Km[7]; Kr = c->Kr[7]; Q(block, Kr, Km);
	Km = c->Km[6]; Kr = c->Kr[6]; Q(block, Kr, Km);
	Km = c->Km[5]; Kr = c->Kr[5]; QBAR(block, Kr, Km);
	Km = c->Km[4]; Kr = c->Kr[4]; QBAR(block, Kr, Km);
	Km = c->Km[3]; Kr = c->Kr[3]; QBAR(block, Kr, Km);
	Km = c->Km[2]; Kr = c->Kr[2]; QBAR(block, Kr, Km);
	Km = c->Km[1]; Kr = c->Kr[1]; QBAR(block, Kr, Km);
	Km = c->Km[0]; Kr = c->Kr[0]; QBAR(block, Kr, Km);

	dst[0] = cpu_to_be32(block[0]);
	dst[1] = cpu_to_be32(block[1]);
	dst[2] = cpu_to_be32(block[2]);
	dst[3] = cpu_to_be32(block[3]);
}

static struct crypto_alg alg = {
	.cra_name = "cast6",
	.cra_flags = CRYPTO_ALG_TYPE_CIPHER,
	.cra_blocksize = CAST6_BLOCK_SIZE,
	.cra_ctxsize = sizeof(struct cast6_ctx),
	.cra_alignmask = 3,
	.cra_module = THIS_MODULE,
	.cra_list = LIST_HEAD_INIT(alg.cra_list),
	.cra_u = {
		  .cipher = {
			     .cia_min_keysize = CAST6_MIN_KEY_SIZE,
			     .cia_max_keysize = CAST6_MAX_KEY_SIZE,
			     .cia_setkey = cast6_setkey,
			     .cia_encrypt = cast6_encrypt,
			     .cia_decrypt = cast6_decrypt}
		  }
};

static int __init cast6_mod_init(void)
{
	return crypto_register_alg(&alg);
}

static void __exit cast6_mod_fini(void)
{
	crypto_unregister_alg(&alg);
}

module_init(cast6_mod_init);
module_exit(cast6_mod_fini);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Cast6 Cipher Algorithm");
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