blowfish.c

/* blowfish.c
 *
 * The blowfish block cipher.
 *
 * For a description of the algorithm, see:
 *   Bruce Schneier: Applied Cryptography. John Wiley & Sons, 1996.
 *   ISBN 0-471-11709-9. Pages 336 ff.
 */

/* NOTE: This file is distributed under the GPL, not the LGPL. */

/* nettle, low-level cryptographics library
 *
 * Copyright (C) 1998, 2001
 *    Free Software Foundation, Inc, Ray Dassen, Niels Mller
 *
 * This file is part of GNUPG.
 *
 * GNUPG 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.
 *
 * GNUPG is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * 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 "blowfish.h"

#include <assert.h>

/* precomputed S boxes */
static const uint32_t ks0[256] = {
    0xD1310BA6,0x98DFB5AC,0x2FFD72DB,0xD01ADFB7,0xB8E1AFED,0x6A267E96,
    0xBA7C9045,0xF12C7F99,0x24A19947,0xB3916CF7,0x0801F2E2,0x858EFC16,
    0x636920D8,0x71574E69,0xA458FEA3,0xF4933D7E,0x0D95748F,0x728EB658,
    0x718BCD58,0x82154AEE,0x7B54A41D,0xC25A59B5,0x9C30D539,0x2AF26013,
    0xC5D1B023,0x286085F0,0xCA417918,0xB8DB38EF,0x8E79DCB0,0x603A180E,
    0x6C9E0E8B,0xB01E8A3E,0xD71577C1,0xBD314B27,0x78AF2FDA,0x55605C60,
    0xE65525F3,0xAA55AB94,0x57489862,0x63E81440,0x55CA396A,0x2AAB10B6,
    0xB4CC5C34,0x1141E8CE,0xA15486AF,0x7C72E993,0xB3EE1411,0x636FBC2A,
    0x2BA9C55D,0x741831F6,0xCE5C3E16,0x9B87931E,0xAFD6BA33,0x6C24CF5C,
    0x7A325381,0x28958677,0x3B8F4898,0x6B4BB9AF,0xC4BFE81B,0x66282193,
    0x61D809CC,0xFB21A991,0x487CAC60,0x5DEC8032,0xEF845D5D,0xE98575B1,
    0xDC262302,0xEB651B88,0x23893E81,0xD396ACC5,0x0F6D6FF3,0x83F44239,
    0x2E0B4482,0xA4842004,0x69C8F04A,0x9E1F9B5E,0x21C66842,0xF6E96C9A,
    0x670C9C61,0xABD388F0,0x6A51A0D2,0xD8542F68,0x960FA728,0xAB5133A3,
    0x6EEF0B6C,0x137A3BE4,0xBA3BF050,0x7EFB2A98,0xA1F1651D,0x39AF0176,
    0x66CA593E,0x82430E88,0x8CEE8619,0x456F9FB4,0x7D84A5C3,0x3B8B5EBE,
    0xE06F75D8,0x85C12073,0x401A449F,0x56C16AA6,0x4ED3AA62,0x363F7706,
    0x1BFEDF72,0x429B023D,0x37D0D724,0xD00A1248,0xDB0FEAD3,0x49F1C09B,
    0x075372C9,0x80991B7B,0x25D479D8,0xF6E8DEF7,0xE3FE501A,0xB6794C3B,
    0x976CE0BD,0x04C006BA,0xC1A94FB6,0x409F60C4,0x5E5C9EC2,0x196A2463,
    0x68FB6FAF,0x3E6C53B5,0x1339B2EB,0x3B52EC6F,0x6DFC511F,0x9B30952C,
    0xCC814544,0xAF5EBD09,0xBEE3D004,0xDE334AFD,0x660F2807,0x192E4BB3,
    0xC0CBA857,0x45C8740F,0xD20B5F39,0xB9D3FBDB,0x5579C0BD,0x1A60320A,
    0xD6A100C6,0x402C7279,0x679F25FE,0xFB1FA3CC,0x8EA5E9F8,0xDB3222F8,
    0x3C7516DF,0xFD616B15,0x2F501EC8,0xAD0552AB,0x323DB5FA,0xFD238760,
    0x53317B48,0x3E00DF82,0x9E5C57BB,0xCA6F8CA0,0x1A87562E,0xDF1769DB,
    0xD542A8F6,0x287EFFC3,0xAC6732C6,0x8C4F5573,0x695B27B0,0xBBCA58C8,
    0xE1FFA35D,0xB8F011A0,0x10FA3D98,0xFD2183B8,0x4AFCB56C,0x2DD1D35B,
    0x9A53E479,0xB6F84565,0xD28E49BC,0x4BFB9790,0xE1DDF2DA,0xA4CB7E33,
    0x62FB1341,0xCEE4C6E8,0xEF20CADA,0x36774C01,0xD07E9EFE,0x2BF11FB4,
    0x95DBDA4D,0xAE909198,0xEAAD8E71,0x6B93D5A0,0xD08ED1D0,0xAFC725E0,
    0x8E3C5B2F,0x8E7594B7,0x8FF6E2FB,0xF2122B64,0x8888B812,0x900DF01C,
    0x4FAD5EA0,0x688FC31C,0xD1CFF191,0xB3A8C1AD,0x2F2F2218,0xBE0E1777,
    0xEA752DFE,0x8B021FA1,0xE5A0CC0F,0xB56F74E8,0x18ACF3D6,0xCE89E299,
    0xB4A84FE0,0xFD13E0B7,0x7CC43B81,0xD2ADA8D9,0x165FA266,0x80957705,
    0x93CC7314,0x211A1477,0xE6AD2065,0x77B5FA86,0xC75442F5,0xFB9D35CF,
    0xEBCDAF0C,0x7B3E89A0,0xD6411BD3,0xAE1E7E49,0x00250E2D,0x2071B35E,
    0x226800BB,0x57B8E0AF,0x2464369B,0xF009B91E,0x5563911D,0x59DFA6AA,
    0x78C14389,0xD95A537F,0x207D5BA2,0x02E5B9C5,0x83260376,0x6295CFA9,
    0x11C81968,0x4E734A41,0xB3472DCA,0x7B14A94A,0x1B510052,0x9A532915,
    0xD60F573F,0xBC9BC6E4,0x2B60A476,0x81E67400,0x08BA6FB5,0x571BE91F,
    0xF296EC6B,0x2A0DD915,0xB6636521,0xE7B9F9B6,0xFF34052E,0xC5855664,
    0x53B02D5D,0xA99F8FA1,0x08BA4799,0x6E85076A };

static const uint32_t ks1[256] = {
    0x4B7A70E9,0xB5B32944,0xDB75092E,0xC4192623,0xAD6EA6B0,0x49A7DF7D,
    0x9CEE60B8,0x8FEDB266,0xECAA8C71,0x699A17FF,0x5664526C,0xC2B19EE1,
    0x193602A5,0x75094C29,0xA0591340,0xE4183A3E,0x3F54989A,0x5B429D65,
    0x6B8FE4D6,0x99F73FD6,0xA1D29C07,0xEFE830F5,0x4D2D38E6,0xF0255DC1,
    0x4CDD2086,0x8470EB26,0x6382E9C6,0x021ECC5E,0x09686B3F,0x3EBAEFC9,
    0x3C971814,0x6B6A70A1,0x687F3584,0x52A0E286,0xB79C5305,0xAA500737,
    0x3E07841C,0x7FDEAE5C,0x8E7D44EC,0x5716F2B8,0xB03ADA37,0xF0500C0D,
    0xF01C1F04,0x0200B3FF,0xAE0CF51A,0x3CB574B2,0x25837A58,0xDC0921BD,
    0xD19113F9,0x7CA92FF6,0x94324773,0x22F54701,0x3AE5E581,0x37C2DADC,
    0xC8B57634,0x9AF3DDA7,0xA9446146,0x0FD0030E,0xECC8C73E,0xA4751E41,
    0xE238CD99,0x3BEA0E2F,0x3280BBA1,0x183EB331,0x4E548B38,0x4F6DB908,
    0x6F420D03,0xF60A04BF,0x2CB81290,0x24977C79,0x5679B072,0xBCAF89AF,
    0xDE9A771F,0xD9930810,0xB38BAE12,0xDCCF3F2E,0x5512721F,0x2E6B7124,
    0x501ADDE6,0x9F84CD87,0x7A584718,0x7408DA17,0xBC9F9ABC,0xE94B7D8C,
    0xEC7AEC3A,0xDB851DFA,0x63094366,0xC464C3D2,0xEF1C1847,0x3215D908,
    0xDD433B37,0x24C2BA16,0x12A14D43,0x2A65C451,0x50940002,0x133AE4DD,
    0x71DFF89E,0x10314E55,0x81AC77D6,0x5F11199B,0x043556F1,0xD7A3C76B,
    0x3C11183B,0x5924A509,0xF28FE6ED,0x97F1FBFA,0x9EBABF2C,0x1E153C6E,
    0x86E34570,0xEAE96FB1,0x860E5E0A,0x5A3E2AB3,0x771FE71C,0x4E3D06FA,
    0x2965DCB9,0x99E71D0F,0x803E89D6,0x5266C825,0x2E4CC978,0x9C10B36A,
    0xC6150EBA,0x94E2EA78,0xA5FC3C53,0x1E0A2DF4,0xF2F74EA7,0x361D2B3D,
    0x1939260F,0x19C27960,0x5223A708,0xF71312B6,0xEBADFE6E,0xEAC31F66,
    0xE3BC4595,0xA67BC883,0xB17F37D1,0x018CFF28,0xC332DDEF,0xBE6C5AA5,
    0x65582185,0x68AB9802,0xEECEA50F,0xDB2F953B,0x2AEF7DAD,0x5B6E2F84,
    0x1521B628,0x29076170,0xECDD4775,0x619F1510,0x13CCA830,0xEB61BD96,
    0x0334FE1E,0xAA0363CF,0xB5735C90,0x4C70A239,0xD59E9E0B,0xCBAADE14,
    0xEECC86BC,0x60622CA7,0x9CAB5CAB,0xB2F3846E,0x648B1EAF,0x19BDF0CA,
    0xA02369B9,0x655ABB50,0x40685A32,0x3C2AB4B3,0x319EE9D5,0xC021B8F7,
    0x9B540B19,0x875FA099,0x95F7997E,0x623D7DA8,0xF837889A,0x97E32D77,
    0x11ED935F,0x16681281,0x0E358829,0xC7E61FD6,0x96DEDFA1,0x7858BA99,
    0x57F584A5,0x1B227263,0x9B83C3FF,0x1AC24696,0xCDB30AEB,0x532E3054,
    0x8FD948E4,0x6DBC3128,0x58EBF2EF,0x34C6FFEA,0xFE28ED61,0xEE7C3C73,
    0x5D4A14D9,0xE864B7E3,0x42105D14,0x203E13E0,0x45EEE2B6,0xA3AAABEA,
    0xDB6C4F15,0xFACB4FD0,0xC742F442,0xEF6ABBB5,0x654F3B1D,0x41CD2105,
    0xD81E799E,0x86854DC7,0xE44B476A,0x3D816250,0xCF62A1F2,0x5B8D2646,
    0xFC8883A0,0xC1C7B6A3,0x7F1524C3,0x69CB7492,0x47848A0B,0x5692B285,
    0x095BBF00,0xAD19489D,0x1462B174,0x23820E00,0x58428D2A,0x0C55F5EA,
    0x1DADF43E,0x233F7061,0x3372F092,0x8D937E41,0xD65FECF1,0x6C223BDB,
    0x7CDE3759,0xCBEE7460,0x4085F2A7,0xCE77326E,0xA6078084,0x19F8509E,
    0xE8EFD855,0x61D99735,0xA969A7AA,0xC50C06C2,0x5A04ABFC,0x800BCADC,
    0x9E447A2E,0xC3453484,0xFDD56705,0x0E1E9EC9,0xDB73DBD3,0x105588CD,
    0x675FDA79,0xE3674340,0xC5C43465,0x713E38D8,0x3D28F89E,0xF16DFF20,
    0x153E21E7,0x8FB03D4A,0xE6E39F2B,0xDB83ADF7 };

static const uint32_t ks2[256] = {
    0xE93D5A68,0x948140F7,0xF64C261C,0x94692934,0x411520F7,0x7602D4F7,
    0xBCF46B2E,0xD4A20068,0xD4082471,0x3320F46A,0x43B7D4B7,0x500061AF,
    0x1E39F62E,0x97244546,0x14214F74,0xBF8B8840,0x4D95FC1D,0x96B591AF,
    0x70F4DDD3,0x66A02F45,0xBFBC09EC,0x03BD9785,0x7FAC6DD0,0x31CB8504,
    0x96EB27B3,0x55FD3941,0xDA2547E6,0xABCA0A9A,0x28507825,0x530429F4,
    0x0A2C86DA,0xE9B66DFB,0x68DC1462,0xD7486900,0x680EC0A4,0x27A18DEE,
    0x4F3FFEA2,0xE887AD8C,0xB58CE006,0x7AF4D6B6,0xAACE1E7C,0xD3375FEC,
    0xCE78A399,0x406B2A42,0x20FE9E35,0xD9F385B9,0xEE39D7AB,0x3B124E8B,
    0x1DC9FAF7,0x4B6D1856,0x26A36631,0xEAE397B2,0x3A6EFA74,0xDD5B4332,
    0x6841E7F7,0xCA7820FB,0xFB0AF54E,0xD8FEB397,0x454056AC,0xBA489527,
    0x55533A3A,0x20838D87,0xFE6BA9B7,0xD096954B,0x55A867BC,0xA1159A58,
    0xCCA92963,0x99E1DB33,0xA62A4A56,0x3F3125F9,0x5EF47E1C,0x9029317C,
    0xFDF8E802,0x04272F70,0x80BB155C,0x05282CE3,0x95C11548,0xE4C66D22,
    0x48C1133F,0xC70F86DC,0x07F9C9EE,0x41041F0F,0x404779A4,0x5D886E17,
    0x325F51EB,0xD59BC0D1,0xF2BCC18F,0x41113564,0x257B7834,0x602A9C60,
    0xDFF8E8A3,0x1F636C1B,0x0E12B4C2,0x02E1329E,0xAF664FD1,0xCAD18115,
    0x6B2395E0,0x333E92E1,0x3B240B62,0xEEBEB922,0x85B2A20E,0xE6BA0D99,
    0xDE720C8C,0x2DA2F728,0xD0127845,0x95B794FD,0x647D0862,0xE7CCF5F0,
    0x5449A36F,0x877D48FA,0xC39DFD27,0xF33E8D1E,0x0A476341,0x992EFF74,
    0x3A6F6EAB,0xF4F8FD37,0xA812DC60,0xA1EBDDF8,0x991BE14C,0xDB6E6B0D,
    0xC67B5510,0x6D672C37,0x2765D43B,0xDCD0E804,0xF1290DC7,0xCC00FFA3,
    0xB5390F92,0x690FED0B,0x667B9FFB,0xCEDB7D9C,0xA091CF0B,0xD9155EA3,
    0xBB132F88,0x515BAD24,0x7B9479BF,0x763BD6EB,0x37392EB3,0xCC115979,
    0x8026E297,0xF42E312D,0x6842ADA7,0xC66A2B3B,0x12754CCC,0x782EF11C,
    0x6A124237,0xB79251E7,0x06A1BBE6,0x4BFB6350,0x1A6B1018,0x11CAEDFA,
    0x3D25BDD8,0xE2E1C3C9,0x44421659,0x0A121386,0xD90CEC6E,0xD5ABEA2A,
    0x64AF674E,0xDA86A85F,0xBEBFE988,0x64E4C3FE,0x9DBC8057,0xF0F7C086,
    0x60787BF8,0x6003604D,0xD1FD8346,0xF6381FB0,0x7745AE04,0xD736FCCC,
    0x83426B33,0xF01EAB71,0xB0804187,0x3C005E5F,0x77A057BE,0xBDE8AE24,
    0x55464299,0xBF582E61,0x4E58F48F,0xF2DDFDA2,0xF474EF38,0x8789BDC2,
    0x5366F9C3,0xC8B38E74,0xB475F255,0x46FCD9B9,0x7AEB2661,0x8B1DDF84,
    0x846A0E79,0x915F95E2,0x466E598E,0x20B45770,0x8CD55591,0xC902DE4C,
    0xB90BACE1,0xBB8205D0,0x11A86248,0x7574A99E,0xB77F19B6,0xE0A9DC09,
    0x662D09A1,0xC4324633,0xE85A1F02,0x09F0BE8C,0x4A99A025,0x1D6EFE10,
    0x1AB93D1D,0x0BA5A4DF,0xA186F20F,0x2868F169,0xDCB7DA83,0x573906FE,
    0xA1E2CE9B,0x4FCD7F52,0x50115E01,0xA70683FA,0xA002B5C4,0x0DE6D027,
    0x9AF88C27,0x773F8641,0xC3604C06,0x61A806B5,0xF0177A28,0xC0F586E0,
    0x006058AA,0x30DC7D62,0x11E69ED7,0x2338EA63,0x53C2DD94,0xC2C21634,
    0xBBCBEE56,0x90BCB6DE,0xEBFC7DA1,0xCE591D76,0x6F05E409,0x4B7C0188,
    0x39720A3D,0x7C927C24,0x86E3725F,0x724D9DB9,0x1AC15BB4,0xD39EB8FC,
    0xED545578,0x08FCA5B5,0xD83D7CD3,0x4DAD0FC4,0x1E50EF5E,0xB161E6F8,
    0xA28514D9,0x6C51133C,0x6FD5C7E7,0x56E14EC4,0x362ABFCE,0xDDC6C837,
    0xD79A3234,0x92638212,0x670EFA8E,0x406000E0 };

static const uint32_t ks3[256] = {
    0x3A39CE37,0xD3FAF5CF,0xABC27737,0x5AC52D1B,0x5CB0679E,0x4FA33742,
    0xD3822740,0x99BC9BBE,0xD5118E9D,0xBF0F7315,0xD62D1C7E,0xC700C47B,
    0xB78C1B6B,0x21A19045,0xB26EB1BE,0x6A366EB4,0x5748AB2F,0xBC946E79,
    0xC6A376D2,0x6549C2C8,0x530FF8EE,0x468DDE7D,0xD5730A1D,0x4CD04DC6,
    0x2939BBDB,0xA9BA4650,0xAC9526E8,0xBE5EE304,0xA1FAD5F0,0x6A2D519A,
    0x63EF8CE2,0x9A86EE22,0xC089C2B8,0x43242EF6,0xA51E03AA,0x9CF2D0A4,
    0x83C061BA,0x9BE96A4D,0x8FE51550,0xBA645BD6,0x2826A2F9,0xA73A3AE1,
    0x4BA99586,0xEF5562E9,0xC72FEFD3,0xF752F7DA,0x3F046F69,0x77FA0A59,
    0x80E4A915,0x87B08601,0x9B09E6AD,0x3B3EE593,0xE990FD5A,0x9E34D797,
    0x2CF0B7D9,0x022B8B51,0x96D5AC3A,0x017DA67D,0xD1CF3ED6,0x7C7D2D28,
    0x1F9F25CF,0xADF2B89B,0x5AD6B472,0x5A88F54C,0xE029AC71,0xE019A5E6,
    0x47B0ACFD,0xED93FA9B,0xE8D3C48D,0x283B57CC,0xF8D56629,0x79132E28,
    0x785F0191,0xED756055,0xF7960E44,0xE3D35E8C,0x15056DD4,0x88F46DBA,
    0x03A16125,0x0564F0BD,0xC3EB9E15,0x3C9057A2,0x97271AEC,0xA93A072A,
    0x1B3F6D9B,0x1E6321F5,0xF59C66FB,0x26DCF319,0x7533D928,0xB155FDF5,
    0x03563482,0x8ABA3CBB,0x28517711,0xC20AD9F8,0xABCC5167,0xCCAD925F,
    0x4DE81751,0x3830DC8E,0x379D5862,0x9320F991,0xEA7A90C2,0xFB3E7BCE,
    0x5121CE64,0x774FBE32,0xA8B6E37E,0xC3293D46,0x48DE5369,0x6413E680,
    0xA2AE0810,0xDD6DB224,0x69852DFD,0x09072166,0xB39A460A,0x6445C0DD,
    0x586CDECF,0x1C20C8AE,0x5BBEF7DD,0x1B588D40,0xCCD2017F,0x6BB4E3BB,
    0xDDA26A7E,0x3A59FF45,0x3E350A44,0xBCB4CDD5,0x72EACEA8,0xFA6484BB,
    0x8D6612AE,0xBF3C6F47,0xD29BE463,0x542F5D9E,0xAEC2771B,0xF64E6370,
    0x740E0D8D,0xE75B1357,0xF8721671,0xAF537D5D,0x4040CB08,0x4EB4E2CC,
    0x34D2466A,0x0115AF84,0xE1B00428,0x95983A1D,0x06B89FB4,0xCE6EA048,
    0x6F3F3B82,0x3520AB82,0x011A1D4B,0x277227F8,0x611560B1,0xE7933FDC,
    0xBB3A792B,0x344525BD,0xA08839E1,0x51CE794B,0x2F32C9B7,0xA01FBAC9,
    0xE01CC87E,0xBCC7D1F6,0xCF0111C3,0xA1E8AAC7,0x1A908749,0xD44FBD9A,
    0xD0DADECB,0xD50ADA38,0x0339C32A,0xC6913667,0x8DF9317C,0xE0B12B4F,
    0xF79E59B7,0x43F5BB3A,0xF2D519FF,0x27D9459C,0xBF97222C,0x15E6FC2A,
    0x0F91FC71,0x9B941525,0xFAE59361,0xCEB69CEB,0xC2A86459,0x12BAA8D1,
    0xB6C1075E,0xE3056A0C,0x10D25065,0xCB03A442,0xE0EC6E0E,0x1698DB3B,
    0x4C98A0BE,0x3278E964,0x9F1F9532,0xE0D392DF,0xD3A0342B,0x8971F21E,
    0x1B0A7441,0x4BA3348C,0xC5BE7120,0xC37632D8,0xDF359F8D,0x9B992F2E,
    0xE60B6F47,0x0FE3F11D,0xE54CDA54,0x1EDAD891,0xCE6279CF,0xCD3E7E6F,
    0x1618B166,0xFD2C1D05,0x848FD2C5,0xF6FB2299,0xF523F357,0xA6327623,
    0x93A83531,0x56CCCD02,0xACF08162,0x5A75EBB5,0x6E163697,0x88D273CC,
    0xDE966292,0x81B949D0,0x4C50901B,0x71C65614,0xE6C6C7BD,0x327A140A,
    0x45E1D006,0xC3F27B9A,0xC9AA53FD,0x62A80F00,0xBB25BFE2,0x35BDD2F6,
    0x71126905,0xB2040222,0xB6CBCF7C,0xCD769C2B,0x53113EC0,0x1640E3D3,
    0x38ABBD60,0x2547ADF0,0xBA38209C,0xF746CE76,0x77AFA1C5,0x20756060,
    0x85CBFE4E,0x8AE88DD8,0x7AAAF9B0,0x4CF9AA7E,0x1948C25C,0x02FB8A8C,
    0x01C36AE4,0xD6EBE1F9,0x90D4F869,0xA65CDEA0,0x3F09252D,0xC208E69F,
    0xB74E6132,0xCE77E25B,0x578FDFE3,0x3AC372E6 };

static const uint32_t ps[_BLOWFISH_ROUNDS+2] = {
    0x243F6A88,0x85A308D3,0x13198A2E,0x03707344,0xA4093822,0x299F31D0,
    0x082EFA98,0xEC4E6C89,0x452821E6,0x38D01377,0xBE5466CF,0x34E90C6C,
    0xC0AC29B7,0xC97C50DD,0x3F84D5B5,0xB5470917,0x9216D5D9,0x8979FB1B };

#if _BLOWFISH_ROUNDS != 16
static inline u32
function_F( BLOWFISH_context *bc, u32 x )
{
    unsigned a, b, c, d;

/* FIXME: I don't quite like this hack. It assumes that the byteorder
 * is plain big or little endian (and for instance not PDP-ish), and
 * that a u32 is exactly 32 bits (while the autoconf stuff only
 * guarantees that it is *at least* 32 bits).
 *
 * On the other hand, taking the address of x makes it difficult to
 * place it in a register, which make me wonder if it will really make
 * the code run any faster. */
#if BIG_ENDIAN_HOST
#warning BIG_ENDIAN hack used
    a = ((byte*)&x)[0];
    b = ((byte*)&x)[1];
    c = ((byte*)&x)[2];
    d = ((byte*)&x)[3];
#elif LITTLE_ENDIAN_HOST
#warning LITTLE_ENDIAN hack used
    a = ((byte*)&x)[3];
    b = ((byte*)&x)[2];
    c = ((byte*)&x)[1];
    d = ((byte*)&x)[0];
#else
    a = x >> 24;
    b = (x >> 16) & 0xff;
    c = (x >> 8) & 0xff;
    d = x & 0xff;
#endif
    return (((bc->s0[a] + bc->s1[b]) ^ bc->s2[c] ) + bc->s3[d]) & 0xffffffff;
}
#endif

#if BIG_ENDIAN_HOST
  #warning BIG_ENDIAN hack used
  #define F(x) ((( s0[((byte*)&x)[0]] + s1[((byte*)&x)[1]])	 \
		   ^ s2[((byte*)&x)[2]]) + s3[((byte*)&x)[3]] )
#elif LITTLE_ENDIAN_HOST
  #warning LITTLE_ENDIAN hack used
  #define F(x) ((( s0[((byte*)&x)[3]] + s1[((byte*)&x)[2]])	 \
		   ^ s2[((byte*)&x)[1]]) + s3[((byte*)&x)[0]] )
#else
  #define F(x) (((( s0[x>>24] + s1[(x>>16) & 0xff]) \
		  ^ s2[(x>>8) & 0xff]) + s3[x & 0xff]) & 0xffffffff)
#endif
#define R(l,r,i)  do { l ^= p[i]; r ^= F(l); } while(0)

static void
encrypt(struct blowfish_ctx *bc, uint32_t *ret_xl, uint32_t *ret_xr)
{
  #if _BLOWFISH_ROUNDS == 16
    uint32_t xl, xr, *s0, *s1, *s2, *s3, *p;

    xl = *ret_xl;
    xr = *ret_xr;
    p = bc->p;
    s0 = bc->s0;
    s1 = bc->s1;
    s2 = bc->s2;
    s3 = bc->s3;

    R( xl, xr,	0);
    R( xr, xl,	1);
    R( xl, xr,	2);
    R( xr, xl,	3);
    R( xl, xr,	4);
    R( xr, xl,	5);
    R( xl, xr,	6);
    R( xr, xl,	7);
    R( xl, xr,	8);
    R( xr, xl,	9);
    R( xl, xr, 10);
    R( xr, xl, 11);
    R( xl, xr, 12);
    R( xr, xl, 13);
    R( xl, xr, 14);
    R( xr, xl, 15);

    xl ^= p[_BLOWFISH_ROUNDS];
    xr ^= p[_BLOWFISH_ROUNDS+1];

    *ret_xl = xr;
    *ret_xr = xl;

  #else
    uint32_t xl, xr, temp, *p;
    int i;

    xl = *ret_xl;
    xr = *ret_xr;
    p = bc->p;

    for(i=0; i < _BLOWFISH_ROUNDS; i++ ) {
	xl ^= p[i];
	xr ^= function_F(bc, xl);
	temp = xl;
	xl = xr;
	xr = temp;
    }
    temp = xl;
    xl = xr;
    xr = temp;

    xr ^= p[_BLOWFISH_ROUNDS];
    xl ^= p[_BLOWFISH_ROUNDS+1];

    *ret_xl = xl;
    *ret_xr = xr;
  #endif
}

static void
decrypt(struct blowfish_ctx *bc, uint32_t *ret_xl, uint32_t *ret_xr )
{
  #if _BLOWFISH_ROUNDS == 16
    uint32_t xl, xr, *s0, *s1, *s2, *s3, *p;

    xl = *ret_xl;
    xr = *ret_xr;
    p = bc->p;
    s0 = bc->s0;
    s1 = bc->s1;
    s2 = bc->s2;
    s3 = bc->s3;

    R( xl, xr, 17);
    R( xr, xl, 16);
    R( xl, xr, 15);
    R( xr, xl, 14);
    R( xl, xr, 13);
    R( xr, xl, 12);
    R( xl, xr, 11);
    R( xr, xl, 10);
    R( xl, xr,	9);
    R( xr, xl,	8);
    R( xl, xr,	7);
    R( xr, xl,	6);
    R( xl, xr,	5);
    R( xr, xl,	4);
    R( xl, xr,	3);
    R( xr, xl,	2);

    xl ^= p[1];
    xr ^= p[0];

    *ret_xl = xr;
    *ret_xr = xl;

  #else
    uint32_t xl, xr, temp, *p;
    int i;

    xl = *ret_xl;
    xr = *ret_xr;
    p = bc->p;

    for(i=_BLOWFISH_ROUNDS+1; i > 1; i-- ) {
	xl ^= p[i];
	xr ^= function_F(bc, xl);
	temp = xl;
	xl = xr;
	xr = temp;
    }

    temp = xl;
    xl = xr;
    xr = temp;

    xr ^= p[1];
    xl ^= p[0];

    *ret_xl = xl;
    *ret_xr = xr;
  #endif
}

#undef F
#undef R

#warning should loop on length.
void
blowfish_encrypt(struct blowfish_ctx *bc, uint32_t length,
                 uint8_t *outbuf, const uint8_t *inbuf)
{
    uint32_t d1, d2;

    assert(!bc->status);
    
    d1 = inbuf[0] << 24 | inbuf[1] << 16 | inbuf[2] << 8 | inbuf[3];
    d2 = inbuf[4] << 24 | inbuf[5] << 16 | inbuf[6] << 8 | inbuf[7];
    encrypt( bc, &d1, &d2 );
    outbuf[0] = (d1 >> 24) & 0xff;
    outbuf[1] = (d1 >> 16) & 0xff;
    outbuf[2] = (d1 >>	8) & 0xff;
    outbuf[3] =  d1	   & 0xff;
    outbuf[4] = (d2 >> 24) & 0xff;
    outbuf[5] = (d2 >> 16) & 0xff;
    outbuf[6] = (d2 >>	8) & 0xff;
    outbuf[7] =  d2	   & 0xff;
}


void
blowfish_decrypt(struct blowfish_ctx *bc, unsigned length,
                 uint8_t *outbuf, const uint8_t *inbuf )
{
    uint32_t d1, d2;

    assert(!bc->status);

    d1 = inbuf[0] << 24 | inbuf[1] << 16 | inbuf[2] << 8 | inbuf[3];
    d2 = inbuf[4] << 24 | inbuf[5] << 16 | inbuf[6] << 8 | inbuf[7];
    decrypt( bc, &d1, &d2 );
    outbuf[0] = (d1 >> 24) & 0xff;
    outbuf[1] = (d1 >> 16) & 0xff;
    outbuf[2] = (d1 >>	8) & 0xff;
    outbuf[3] =  d1	   & 0xff;
    outbuf[4] = (d2 >> 24) & 0xff;
    outbuf[5] = (d2 >> 16) & 0xff;
    outbuf[6] = (d2 >>	8) & 0xff;
    outbuf[7] =  d2	   & 0xff;
}

int
blowfish_set_key(struct blowfish_ctx *ctx,
                 uint32_t keylen, const uint8_t *key)
{
    int i, j;
    uint32_t data, datal, datar;

#if 0
    static int initialized = 0;

    if( !initialized ) {
	initialized = 1;
	assert(selftest());
    }
#endif
    
    for(i=0; i < _BLOWFISH_ROUNDS+2; i++ )
        ctx->p[i] = ps[i];
    for(i=0; i < 256; i++ ) {
	ctx->s0[i] = ks0[i];
	ctx->s1[i] = ks1[i];
	ctx->s2[i] = ks2[i];
	ctx->s3[i] = ks3[i];
    }

    for(i=j=0; i < _BLOWFISH_ROUNDS+2; i++ ) {
      #if BIG_ENDIAN_HOST
        #werror BIG_ENDIAN hack used
	((byte*)&data)[0] = key[j];
	((byte*)&data)[1] = key[(j+1)%keylen];
	((byte*)&data)[2] = key[(j+2)%keylen];
	((byte*)&data)[3] = key[(j+3)%keylen];
      #elif LITTLE_ENDIAN_HOST
	#werror LITTLE_ENDIAN hack used
	((byte*)&data)[3] = key[j];
	((byte*)&data)[2] = key[(j+1)%keylen];
	((byte*)&data)[1] = key[(j+2)%keylen];
	((byte*)&data)[0] = key[(j+3)%keylen];
      #else
	data = key[j] << 24 | key[(j+1) % keylen] <<16
	  | key[(j+2)%keylen] << 8 | key[(j+3)%keylen];
      #endif
	ctx->p[i] ^= data;
	j = (j+4) % keylen;
    }

    datal = datar = 0;
    for(i=0; i < _BLOWFISH_ROUNDS+2; i += 2 ) {
	encrypt( ctx, &datal, &datar );
	ctx->p[i]   = datal;
	ctx->p[i+1] = datar;
    }
    for(i=0; i < 256; i += 2 )	{
	encrypt( ctx, &datal, &datar );
	ctx->s0[i]   = datal;
	ctx->s0[i+1] = datar;
    }
    for(i=0; i < 256; i += 2 )	{
	encrypt( ctx, &datal, &datar );
	ctx->s1[i]   = datal;
	ctx->s1[i+1] = datar;
    }
    for(i=0; i < 256; i += 2 )	{
	encrypt( ctx, &datal, &datar );
	ctx->s2[i]   = datal;
	ctx->s2[i+1] = datar;
    }
    for(i=0; i < 256; i += 2 )	{
	encrypt( ctx, &datal, &datar );
	ctx->s3[i]   = datal;
	ctx->s3[i+1] = datar;
    }

    ctx->status = BLOWFISH_WEAK_KEY;

    /* Check for weak key.  A weak key is a key in which a value in */
    /* the P-array (here c) occurs more than once per table.	    */
    for(i=0; i < 255; i++ ) {
	for( j=i+1; j < 256; j++) {
	    if( (ctx->s0[i] == ctx->s0[j]) || (ctx->s1[i] == ctx->s1[j]) ||
		(ctx->s2[i] == ctx->s2[j]) || (ctx->s3[i] == ctx->s3[j]) )
		return 0;
	}
    }

    ctx->status = BLOWFISH_OK;
    return 1;
}