FFXIVLauncher-Netmaui

1
// NOTE: This file is copy-pasted almost *as-is* from the previous work `Aither.Crypto`
2
//       hence currently it does not follow XL's naming convetions.
3
//       
4
//       It's totally okay to change this. But for now, this is what it is atm.
5
// ReSharper disable InconsistentNaming
6

7
using System;
8
using System.Runtime.CompilerServices;
9

10
namespace XIVLauncher.Common.Encryption.BlockCipher
11
{
12
    internal unsafe struct BlowfishState
13
    {
14
        // References:
15
        // https://www.schneier.com/academic/archives/1994/09/description_of_a_new.html
16
        // http://www.herongyang.com/Blowfish/Algorithm-Blowfish-Cipher-Encryption-Algorithm.html
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        // https://en.wikipedia.org/wiki/Blowfish_(cipher)
18

19
        private const int Rounds = 16;
20
        public const int PSize = 18;
21
        public const int SSize = 256;
22

23
        private static readonly uint[] PInit = new uint[]
24
        {
25
            0x243F6A88, 0x85A308D3, 0x13198A2E, 0x03707344, 0xA4093822, 0x299F31D0,
26
            0x082EFA98, 0xEC4E6C89, 0x452821E6, 0x38D01377, 0xBE5466CF, 0x34E90C6C,
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            0xC0AC29B7, 0xC97C50DD, 0x3F84D5B5, 0xB5470917, 0x9216D5D9, 0x8979FB1B
28
        };
29

30
        private static readonly uint[] S0Init = new uint[]
31
        {
32
            0xD1310BA6, 0x98DFB5AC, 0x2FFD72DB, 0xD01ADFB7, 0xB8E1AFED, 0x6A267E96, 0xBA7C9045, 0xF12C7F99,
33
            0x24A19947, 0xB3916CF7, 0x0801F2E2, 0x858EFC16, 0x636920D8, 0x71574E69, 0xA458FEA3, 0xF4933D7E,
34
            0x0D95748F, 0x728EB658, 0x718BCD58, 0x82154AEE, 0x7B54A41D, 0xC25A59B5, 0x9C30D539, 0x2AF26013,
35
            0xC5D1B023, 0x286085F0, 0xCA417918, 0xB8DB38EF, 0x8E79DCB0, 0x603A180E, 0x6C9E0E8B, 0xB01E8A3E,
36
            0xD71577C1, 0xBD314B27, 0x78AF2FDA, 0x55605C60, 0xE65525F3, 0xAA55AB94, 0x57489862, 0x63E81440,
37
            0x55CA396A, 0x2AAB10B6, 0xB4CC5C34, 0x1141E8CE, 0xA15486AF, 0x7C72E993, 0xB3EE1411, 0x636FBC2A,
38
            0x2BA9C55D, 0x741831F6, 0xCE5C3E16, 0x9B87931E, 0xAFD6BA33, 0x6C24CF5C, 0x7A325381, 0x28958677,
39
            0x3B8F4898, 0x6B4BB9AF, 0xC4BFE81B, 0x66282193, 0x61D809CC, 0xFB21A991, 0x487CAC60, 0x5DEC8032,
40
            0xEF845D5D, 0xE98575B1, 0xDC262302, 0xEB651B88, 0x23893E81, 0xD396ACC5, 0x0F6D6FF3, 0x83F44239,
41
            0x2E0B4482, 0xA4842004, 0x69C8F04A, 0x9E1F9B5E, 0x21C66842, 0xF6E96C9A, 0x670C9C61, 0xABD388F0,
42
            0x6A51A0D2, 0xD8542F68, 0x960FA728, 0xAB5133A3, 0x6EEF0B6C, 0x137A3BE4, 0xBA3BF050, 0x7EFB2A98,
43
            0xA1F1651D, 0x39AF0176, 0x66CA593E, 0x82430E88, 0x8CEE8619, 0x456F9FB4, 0x7D84A5C3, 0x3B8B5EBE,
44
            0xE06F75D8, 0x85C12073, 0x401A449F, 0x56C16AA6, 0x4ED3AA62, 0x363F7706, 0x1BFEDF72, 0x429B023D,
45
            0x37D0D724, 0xD00A1248, 0xDB0FEAD3, 0x49F1C09B, 0x075372C9, 0x80991B7B, 0x25D479D8, 0xF6E8DEF7,
46
            0xE3FE501A, 0xB6794C3B, 0x976CE0BD, 0x04C006BA, 0xC1A94FB6, 0x409F60C4, 0x5E5C9EC2, 0x196A2463,
47
            0x68FB6FAF, 0x3E6C53B5, 0x1339B2EB, 0x3B52EC6F, 0x6DFC511F, 0x9B30952C, 0xCC814544, 0xAF5EBD09,
48
            0xBEE3D004, 0xDE334AFD, 0x660F2807, 0x192E4BB3, 0xC0CBA857, 0x45C8740F, 0xD20B5F39, 0xB9D3FBDB,
49
            0x5579C0BD, 0x1A60320A, 0xD6A100C6, 0x402C7279, 0x679F25FE, 0xFB1FA3CC, 0x8EA5E9F8, 0xDB3222F8,
50
            0x3C7516DF, 0xFD616B15, 0x2F501EC8, 0xAD0552AB, 0x323DB5FA, 0xFD238760, 0x53317B48, 0x3E00DF82,
51
            0x9E5C57BB, 0xCA6F8CA0, 0x1A87562E, 0xDF1769DB, 0xD542A8F6, 0x287EFFC3, 0xAC6732C6, 0x8C4F5573,
52
            0x695B27B0, 0xBBCA58C8, 0xE1FFA35D, 0xB8F011A0, 0x10FA3D98, 0xFD2183B8, 0x4AFCB56C, 0x2DD1D35B,
53
            0x9A53E479, 0xB6F84565, 0xD28E49BC, 0x4BFB9790, 0xE1DDF2DA, 0xA4CB7E33, 0x62FB1341, 0xCEE4C6E8,
54
            0xEF20CADA, 0x36774C01, 0xD07E9EFE, 0x2BF11FB4, 0x95DBDA4D, 0xAE909198, 0xEAAD8E71, 0x6B93D5A0,
55
            0xD08ED1D0, 0xAFC725E0, 0x8E3C5B2F, 0x8E7594B7, 0x8FF6E2FB, 0xF2122B64, 0x8888B812, 0x900DF01C,
56
            0x4FAD5EA0, 0x688FC31C, 0xD1CFF191, 0xB3A8C1AD, 0x2F2F2218, 0xBE0E1777, 0xEA752DFE, 0x8B021FA1,
57
            0xE5A0CC0F, 0xB56F74E8, 0x18ACF3D6, 0xCE89E299, 0xB4A84FE0, 0xFD13E0B7, 0x7CC43B81, 0xD2ADA8D9,
58
            0x165FA266, 0x80957705, 0x93CC7314, 0x211A1477, 0xE6AD2065, 0x77B5FA86, 0xC75442F5, 0xFB9D35CF,
59
            0xEBCDAF0C, 0x7B3E89A0, 0xD6411BD3, 0xAE1E7E49, 0x00250E2D, 0x2071B35E, 0x226800BB, 0x57B8E0AF,
60
            0x2464369B, 0xF009B91E, 0x5563911D, 0x59DFA6AA, 0x78C14389, 0xD95A537F, 0x207D5BA2, 0x02E5B9C5,
61
            0x83260376, 0x6295CFA9, 0x11C81968, 0x4E734A41, 0xB3472DCA, 0x7B14A94A, 0x1B510052, 0x9A532915,
62
            0xD60F573F, 0xBC9BC6E4, 0x2B60A476, 0x81E67400, 0x08BA6FB5, 0x571BE91F, 0xF296EC6B, 0x2A0DD915,
63
            0xB6636521, 0xE7B9F9B6, 0xFF34052E, 0xC5855664, 0x53B02D5D, 0xA99F8FA1, 0x08BA4799, 0x6E85076A
64
        };
65

66
        private static readonly uint[] S1Init = new uint[]
67
        {
68
            0x4B7A70E9, 0xB5B32944, 0xDB75092E, 0xC4192623, 0xAD6EA6B0, 0x49A7DF7D, 0x9CEE60B8, 0x8FEDB266,
69
            0xECAA8C71, 0x699A17FF, 0x5664526C, 0xC2B19EE1, 0x193602A5, 0x75094C29, 0xA0591340, 0xE4183A3E,
70
            0x3F54989A, 0x5B429D65, 0x6B8FE4D6, 0x99F73FD6, 0xA1D29C07, 0xEFE830F5, 0x4D2D38E6, 0xF0255DC1,
71
            0x4CDD2086, 0x8470EB26, 0x6382E9C6, 0x021ECC5E, 0x09686B3F, 0x3EBAEFC9, 0x3C971814, 0x6B6A70A1,
72
            0x687F3584, 0x52A0E286, 0xB79C5305, 0xAA500737, 0x3E07841C, 0x7FDEAE5C, 0x8E7D44EC, 0x5716F2B8,
73
            0xB03ADA37, 0xF0500C0D, 0xF01C1F04, 0x0200B3FF, 0xAE0CF51A, 0x3CB574B2, 0x25837A58, 0xDC0921BD,
74
            0xD19113F9, 0x7CA92FF6, 0x94324773, 0x22F54701, 0x3AE5E581, 0x37C2DADC, 0xC8B57634, 0x9AF3DDA7,
75
            0xA9446146, 0x0FD0030E, 0xECC8C73E, 0xA4751E41, 0xE238CD99, 0x3BEA0E2F, 0x3280BBA1, 0x183EB331,
76
            0x4E548B38, 0x4F6DB908, 0x6F420D03, 0xF60A04BF, 0x2CB81290, 0x24977C79, 0x5679B072, 0xBCAF89AF,
77
            0xDE9A771F, 0xD9930810, 0xB38BAE12, 0xDCCF3F2E, 0x5512721F, 0x2E6B7124, 0x501ADDE6, 0x9F84CD87,
78
            0x7A584718, 0x7408DA17, 0xBC9F9ABC, 0xE94B7D8C, 0xEC7AEC3A, 0xDB851DFA, 0x63094366, 0xC464C3D2,
79
            0xEF1C1847, 0x3215D908, 0xDD433B37, 0x24C2BA16, 0x12A14D43, 0x2A65C451, 0x50940002, 0x133AE4DD,
80
            0x71DFF89E, 0x10314E55, 0x81AC77D6, 0x5F11199B, 0x043556F1, 0xD7A3C76B, 0x3C11183B, 0x5924A509,
81
            0xF28FE6ED, 0x97F1FBFA, 0x9EBABF2C, 0x1E153C6E, 0x86E34570, 0xEAE96FB1, 0x860E5E0A, 0x5A3E2AB3,
82
            0x771FE71C, 0x4E3D06FA, 0x2965DCB9, 0x99E71D0F, 0x803E89D6, 0x5266C825, 0x2E4CC978, 0x9C10B36A,
83
            0xC6150EBA, 0x94E2EA78, 0xA5FC3C53, 0x1E0A2DF4, 0xF2F74EA7, 0x361D2B3D, 0x1939260F, 0x19C27960,
84
            0x5223A708, 0xF71312B6, 0xEBADFE6E, 0xEAC31F66, 0xE3BC4595, 0xA67BC883, 0xB17F37D1, 0x018CFF28,
85
            0xC332DDEF, 0xBE6C5AA5, 0x65582185, 0x68AB9802, 0xEECEA50F, 0xDB2F953B, 0x2AEF7DAD, 0x5B6E2F84,
86
            0x1521B628, 0x29076170, 0xECDD4775, 0x619F1510, 0x13CCA830, 0xEB61BD96, 0x0334FE1E, 0xAA0363CF,
87
            0xB5735C90, 0x4C70A239, 0xD59E9E0B, 0xCBAADE14, 0xEECC86BC, 0x60622CA7, 0x9CAB5CAB, 0xB2F3846E,
88
            0x648B1EAF, 0x19BDF0CA, 0xA02369B9, 0x655ABB50, 0x40685A32, 0x3C2AB4B3, 0x319EE9D5, 0xC021B8F7,
89
            0x9B540B19, 0x875FA099, 0x95F7997E, 0x623D7DA8, 0xF837889A, 0x97E32D77, 0x11ED935F, 0x16681281,
90
            0x0E358829, 0xC7E61FD6, 0x96DEDFA1, 0x7858BA99, 0x57F584A5, 0x1B227263, 0x9B83C3FF, 0x1AC24696,
91
            0xCDB30AEB, 0x532E3054, 0x8FD948E4, 0x6DBC3128, 0x58EBF2EF, 0x34C6FFEA, 0xFE28ED61, 0xEE7C3C73,
92
            0x5D4A14D9, 0xE864B7E3, 0x42105D14, 0x203E13E0, 0x45EEE2B6, 0xA3AAABEA, 0xDB6C4F15, 0xFACB4FD0,
93
            0xC742F442, 0xEF6ABBB5, 0x654F3B1D, 0x41CD2105, 0xD81E799E, 0x86854DC7, 0xE44B476A, 0x3D816250,
94
            0xCF62A1F2, 0x5B8D2646, 0xFC8883A0, 0xC1C7B6A3, 0x7F1524C3, 0x69CB7492, 0x47848A0B, 0x5692B285,
95
            0x095BBF00, 0xAD19489D, 0x1462B174, 0x23820E00, 0x58428D2A, 0x0C55F5EA, 0x1DADF43E, 0x233F7061,
96
            0x3372F092, 0x8D937E41, 0xD65FECF1, 0x6C223BDB, 0x7CDE3759, 0xCBEE7460, 0x4085F2A7, 0xCE77326E,
97
            0xA6078084, 0x19F8509E, 0xE8EFD855, 0x61D99735, 0xA969A7AA, 0xC50C06C2, 0x5A04ABFC, 0x800BCADC,
98
            0x9E447A2E, 0xC3453484, 0xFDD56705, 0x0E1E9EC9, 0xDB73DBD3, 0x105588CD, 0x675FDA79, 0xE3674340,
99
            0xC5C43465, 0x713E38D8, 0x3D28F89E, 0xF16DFF20, 0x153E21E7, 0x8FB03D4A, 0xE6E39F2B, 0xDB83ADF7
100
        };
101

102
        private static readonly uint[] S2Init = new uint[]
103
        {
104
            0xE93D5A68, 0x948140F7, 0xF64C261C, 0x94692934, 0x411520F7, 0x7602D4F7, 0xBCF46B2E, 0xD4A20068,
105
            0xD4082471, 0x3320F46A, 0x43B7D4B7, 0x500061AF, 0x1E39F62E, 0x97244546, 0x14214F74, 0xBF8B8840,
106
            0x4D95FC1D, 0x96B591AF, 0x70F4DDD3, 0x66A02F45, 0xBFBC09EC, 0x03BD9785, 0x7FAC6DD0, 0x31CB8504,
107
            0x96EB27B3, 0x55FD3941, 0xDA2547E6, 0xABCA0A9A, 0x28507825, 0x530429F4, 0x0A2C86DA, 0xE9B66DFB,
108
            0x68DC1462, 0xD7486900, 0x680EC0A4, 0x27A18DEE, 0x4F3FFEA2, 0xE887AD8C, 0xB58CE006, 0x7AF4D6B6,
109
            0xAACE1E7C, 0xD3375FEC, 0xCE78A399, 0x406B2A42, 0x20FE9E35, 0xD9F385B9, 0xEE39D7AB, 0x3B124E8B,
110
            0x1DC9FAF7, 0x4B6D1856, 0x26A36631, 0xEAE397B2, 0x3A6EFA74, 0xDD5B4332, 0x6841E7F7, 0xCA7820FB,
111
            0xFB0AF54E, 0xD8FEB397, 0x454056AC, 0xBA489527, 0x55533A3A, 0x20838D87, 0xFE6BA9B7, 0xD096954B,
112
            0x55A867BC, 0xA1159A58, 0xCCA92963, 0x99E1DB33, 0xA62A4A56, 0x3F3125F9, 0x5EF47E1C, 0x9029317C,
113
            0xFDF8E802, 0x04272F70, 0x80BB155C, 0x05282CE3, 0x95C11548, 0xE4C66D22, 0x48C1133F, 0xC70F86DC,
114
            0x07F9C9EE, 0x41041F0F, 0x404779A4, 0x5D886E17, 0x325F51EB, 0xD59BC0D1, 0xF2BCC18F, 0x41113564,
115
            0x257B7834, 0x602A9C60, 0xDFF8E8A3, 0x1F636C1B, 0x0E12B4C2, 0x02E1329E, 0xAF664FD1, 0xCAD18115,
116
            0x6B2395E0, 0x333E92E1, 0x3B240B62, 0xEEBEB922, 0x85B2A20E, 0xE6BA0D99, 0xDE720C8C, 0x2DA2F728,
117
            0xD0127845, 0x95B794FD, 0x647D0862, 0xE7CCF5F0, 0x5449A36F, 0x877D48FA, 0xC39DFD27, 0xF33E8D1E,
118
            0x0A476341, 0x992EFF74, 0x3A6F6EAB, 0xF4F8FD37, 0xA812DC60, 0xA1EBDDF8, 0x991BE14C, 0xDB6E6B0D,
119
            0xC67B5510, 0x6D672C37, 0x2765D43B, 0xDCD0E804, 0xF1290DC7, 0xCC00FFA3, 0xB5390F92, 0x690FED0B,
120
            0x667B9FFB, 0xCEDB7D9C, 0xA091CF0B, 0xD9155EA3, 0xBB132F88, 0x515BAD24, 0x7B9479BF, 0x763BD6EB,
121
            0x37392EB3, 0xCC115979, 0x8026E297, 0xF42E312D, 0x6842ADA7, 0xC66A2B3B, 0x12754CCC, 0x782EF11C,
122
            0x6A124237, 0xB79251E7, 0x06A1BBE6, 0x4BFB6350, 0x1A6B1018, 0x11CAEDFA, 0x3D25BDD8, 0xE2E1C3C9,
123
            0x44421659, 0x0A121386, 0xD90CEC6E, 0xD5ABEA2A, 0x64AF674E, 0xDA86A85F, 0xBEBFE988, 0x64E4C3FE,
124
            0x9DBC8057, 0xF0F7C086, 0x60787BF8, 0x6003604D, 0xD1FD8346, 0xF6381FB0, 0x7745AE04, 0xD736FCCC,
125
            0x83426B33, 0xF01EAB71, 0xB0804187, 0x3C005E5F, 0x77A057BE, 0xBDE8AE24, 0x55464299, 0xBF582E61,
126
            0x4E58F48F, 0xF2DDFDA2, 0xF474EF38, 0x8789BDC2, 0x5366F9C3, 0xC8B38E74, 0xB475F255, 0x46FCD9B9,
127
            0x7AEB2661, 0x8B1DDF84, 0x846A0E79, 0x915F95E2, 0x466E598E, 0x20B45770, 0x8CD55591, 0xC902DE4C,
128
            0xB90BACE1, 0xBB8205D0, 0x11A86248, 0x7574A99E, 0xB77F19B6, 0xE0A9DC09, 0x662D09A1, 0xC4324633,
129
            0xE85A1F02, 0x09F0BE8C, 0x4A99A025, 0x1D6EFE10, 0x1AB93D1D, 0x0BA5A4DF, 0xA186F20F, 0x2868F169,
130
            0xDCB7DA83, 0x573906FE, 0xA1E2CE9B, 0x4FCD7F52, 0x50115E01, 0xA70683FA, 0xA002B5C4, 0x0DE6D027,
131
            0x9AF88C27, 0x773F8641, 0xC3604C06, 0x61A806B5, 0xF0177A28, 0xC0F586E0, 0x006058AA, 0x30DC7D62,
132
            0x11E69ED7, 0x2338EA63, 0x53C2DD94, 0xC2C21634, 0xBBCBEE56, 0x90BCB6DE, 0xEBFC7DA1, 0xCE591D76,
133
            0x6F05E409, 0x4B7C0188, 0x39720A3D, 0x7C927C24, 0x86E3725F, 0x724D9DB9, 0x1AC15BB4, 0xD39EB8FC,
134
            0xED545578, 0x08FCA5B5, 0xD83D7CD3, 0x4DAD0FC4, 0x1E50EF5E, 0xB161E6F8, 0xA28514D9, 0x6C51133C,
135
            0x6FD5C7E7, 0x56E14EC4, 0x362ABFCE, 0xDDC6C837, 0xD79A3234, 0x92638212, 0x670EFA8E, 0x406000E0
136
        };
137

138
        private static readonly uint[] S3Init = new uint[]
139
        {
140
            0x3A39CE37, 0xD3FAF5CF, 0xABC27737, 0x5AC52D1B, 0x5CB0679E, 0x4FA33742, 0xD3822740, 0x99BC9BBE,
141
            0xD5118E9D, 0xBF0F7315, 0xD62D1C7E, 0xC700C47B, 0xB78C1B6B, 0x21A19045, 0xB26EB1BE, 0x6A366EB4,
142
            0x5748AB2F, 0xBC946E79, 0xC6A376D2, 0x6549C2C8, 0x530FF8EE, 0x468DDE7D, 0xD5730A1D, 0x4CD04DC6,
143
            0x2939BBDB, 0xA9BA4650, 0xAC9526E8, 0xBE5EE304, 0xA1FAD5F0, 0x6A2D519A, 0x63EF8CE2, 0x9A86EE22,
144
            0xC089C2B8, 0x43242EF6, 0xA51E03AA, 0x9CF2D0A4, 0x83C061BA, 0x9BE96A4D, 0x8FE51550, 0xBA645BD6,
145
            0x2826A2F9, 0xA73A3AE1, 0x4BA99586, 0xEF5562E9, 0xC72FEFD3, 0xF752F7DA, 0x3F046F69, 0x77FA0A59,
146
            0x80E4A915, 0x87B08601, 0x9B09E6AD, 0x3B3EE593, 0xE990FD5A, 0x9E34D797, 0x2CF0B7D9, 0x022B8B51,
147
            0x96D5AC3A, 0x017DA67D, 0xD1CF3ED6, 0x7C7D2D28, 0x1F9F25CF, 0xADF2B89B, 0x5AD6B472, 0x5A88F54C,
148
            0xE029AC71, 0xE019A5E6, 0x47B0ACFD, 0xED93FA9B, 0xE8D3C48D, 0x283B57CC, 0xF8D56629, 0x79132E28,
149
            0x785F0191, 0xED756055, 0xF7960E44, 0xE3D35E8C, 0x15056DD4, 0x88F46DBA, 0x03A16125, 0x0564F0BD,
150
            0xC3EB9E15, 0x3C9057A2, 0x97271AEC, 0xA93A072A, 0x1B3F6D9B, 0x1E6321F5, 0xF59C66FB, 0x26DCF319,
151
            0x7533D928, 0xB155FDF5, 0x03563482, 0x8ABA3CBB, 0x28517711, 0xC20AD9F8, 0xABCC5167, 0xCCAD925F,
152
            0x4DE81751, 0x3830DC8E, 0x379D5862, 0x9320F991, 0xEA7A90C2, 0xFB3E7BCE, 0x5121CE64, 0x774FBE32,
153
            0xA8B6E37E, 0xC3293D46, 0x48DE5369, 0x6413E680, 0xA2AE0810, 0xDD6DB224, 0x69852DFD, 0x09072166,
154
            0xB39A460A, 0x6445C0DD, 0x586CDECF, 0x1C20C8AE, 0x5BBEF7DD, 0x1B588D40, 0xCCD2017F, 0x6BB4E3BB,
155
            0xDDA26A7E, 0x3A59FF45, 0x3E350A44, 0xBCB4CDD5, 0x72EACEA8, 0xFA6484BB, 0x8D6612AE, 0xBF3C6F47,
156
            0xD29BE463, 0x542F5D9E, 0xAEC2771B, 0xF64E6370, 0x740E0D8D, 0xE75B1357, 0xF8721671, 0xAF537D5D,
157
            0x4040CB08, 0x4EB4E2CC, 0x34D2466A, 0x0115AF84, 0xE1B00428, 0x95983A1D, 0x06B89FB4, 0xCE6EA048,
158
            0x6F3F3B82, 0x3520AB82, 0x011A1D4B, 0x277227F8, 0x611560B1, 0xE7933FDC, 0xBB3A792B, 0x344525BD,
159
            0xA08839E1, 0x51CE794B, 0x2F32C9B7, 0xA01FBAC9, 0xE01CC87E, 0xBCC7D1F6, 0xCF0111C3, 0xA1E8AAC7,
160
            0x1A908749, 0xD44FBD9A, 0xD0DADECB, 0xD50ADA38, 0x0339C32A, 0xC6913667, 0x8DF9317C, 0xE0B12B4F,
161
            0xF79E59B7, 0x43F5BB3A, 0xF2D519FF, 0x27D9459C, 0xBF97222C, 0x15E6FC2A, 0x0F91FC71, 0x9B941525,
162
            0xFAE59361, 0xCEB69CEB, 0xC2A86459, 0x12BAA8D1, 0xB6C1075E, 0xE3056A0C, 0x10D25065, 0xCB03A442,
163
            0xE0EC6E0E, 0x1698DB3B, 0x4C98A0BE, 0x3278E964, 0x9F1F9532, 0xE0D392DF, 0xD3A0342B, 0x8971F21E,
164
            0x1B0A7441, 0x4BA3348C, 0xC5BE7120, 0xC37632D8, 0xDF359F8D, 0x9B992F2E, 0xE60B6F47, 0x0FE3F11D,
165
            0xE54CDA54, 0x1EDAD891, 0xCE6279CF, 0xCD3E7E6F, 0x1618B166, 0xFD2C1D05, 0x848FD2C5, 0xF6FB2299,
166
            0xF523F357, 0xA6327623, 0x93A83531, 0x56CCCD02, 0xACF08162, 0x5A75EBB5, 0x6E163697, 0x88D273CC,
167
            0xDE966292, 0x81B949D0, 0x4C50901B, 0x71C65614, 0xE6C6C7BD, 0x327A140A, 0x45E1D006, 0xC3F27B9A,
168
            0xC9AA53FD, 0x62A80F00, 0xBB25BFE2, 0x35BDD2F6, 0x71126905, 0xB2040222, 0xB6CBCF7C, 0xCD769C2B,
169
            0x53113EC0, 0x1640E3D3, 0x38ABBD60, 0x2547ADF0, 0xBA38209C, 0xF746CE76, 0x77AFA1C5, 0x20756060,
170
            0x85CBFE4E, 0x8AE88DD8, 0x7AAAF9B0, 0x4CF9AA7E, 0x1948C25C, 0x02FB8A8C, 0x01C36AE4, 0xD6EBE1F9,
171
            0x90D4F869, 0xA65CDEA0, 0x3F09252D, 0xC208E69F, 0xB74E6132, 0xCE77E25B, 0x578FDFE3, 0x3AC372E6
172
        };
173

174
        private fixed uint m_p[PSize];
175
        private fixed uint m_s0[SSize];
176
        private fixed uint m_s1[SSize];
177
        private fixed uint m_s2[SSize];
178
        private fixed uint m_s3[SSize];
179

180
        public BlowfishState(ReadOnlySpan<byte> key)
181
        {
182
            CheckKeyLength(key);
183

184
            // initializes P-array and S-boxes to initial values.
185
            fixed (uint* pSrc = PInit)
186
            fixed (uint* pDst = m_p)
187
            {
188
                Buffer.MemoryCopy(pSrc, pDst, PSize * 4, PSize * 4);
189
            }
190

191
            fixed (uint* pSrc = S0Init)
192
            fixed (uint* pDst = m_s0)
193
            {
194
                Buffer.MemoryCopy(pSrc, pDst, SSize * 4, SSize * 4);
195
            }
196

197
            fixed (uint* pSrc = S1Init)
198
            fixed (uint* pDst = m_s1)
199
            {
200
                Buffer.MemoryCopy(pSrc, pDst, SSize * 4, SSize * 4);
201
            }
202

203
            fixed (uint* pSrc = S2Init)
204
            fixed (uint* pDst = m_s2)
205
            {
206
                Buffer.MemoryCopy(pSrc, pDst, SSize * 4, SSize * 4);
207
            }
208

209
            fixed (uint* pSrc = S3Init)
210
            fixed (uint* pDst = m_s3)
211
            {
212
                Buffer.MemoryCopy(pSrc, pDst, SSize * 4, SSize * 4);
213
            }
214

215
            InitKey(key);
216
        }
217

218
        private void CheckKeyLength(ReadOnlySpan<byte> key)
219
        {
220
            // Supported key sizes: 32–448 bits
221
            // https://en.wikipedia.org/wiki/Blowfish_(cipher)#The_algorithm
222
            if (key.Length < 4 || key.Length > 56)
223
            {
224
                throw new ArgumentException("Key length must be between from 32 to 448 bits.", nameof(key));
225
            }
226
        }
227

228
        /// <summary>
229
        /// Encrypts a block.
230
        /// </summary>
231
        /// <param name="xl">A left side of the block.</param>
232
        /// <param name="xr">A right side of the block.</param>
233
        public (uint, uint) EncryptBlock(uint xl, uint xr)
234
        {
235
            // https://en.wikipedia.org/wiki/Feistel_cipher#Construction_details
236
            for (var i = 0; i < Rounds; i += 2)
237
            {
238
                xl ^= m_p[i];
239
                xr ^= Round(xl);
240
                xr ^= m_p[i + 1];
241
                xl ^= Round(xr);
242
            }
243

244
            xl ^= m_p[16];
245
            xr ^= m_p[17];
246

247
            // swap(L, R)
248
            var temp = xl;
249
            xl = xr;
250
            xr = temp;
251

252
            return (xl, xr);
253
        }
254

255
        /// <summary>
256
        /// Decrypts a block.
257
        /// </summary>
258
        /// <param name="xl">A left side of the block.</param>
259
        /// <param name="xr">A right side of the blick.</param>
260
        public (uint, uint) DecryptBlock(uint xl, uint xr)
261
        {
262
            // https://en.wikipedia.org/wiki/Feistel_cipher#Construction_details
263
            for (var i = Rounds; i > 0; i -= 2)
264
            {
265
                xl ^= m_p[i + 1];
266
                xr ^= Round(xr);
267
                xr ^= m_p[i];
268
                xr ^= Round(xr);
269
            }
270

271
            xl ^= m_p[1];
272
            xr ^= m_p[0];
273

274
            // swap(L, R);
275
            var temp = xl;
276
            xl = xr;
277
            xr = temp;
278

279
            return (xl, xr);
280
        }
281

282
        /// <summary>
283
        /// Initializes P-array and S-boxes with given key. P-array and S-boxes must be initialized to initial values beforehand.
284
        /// </summary>
285
        /// <param name="key">A setup key.</param>
286
        private void InitKey(ReadOnlySpan<byte> key)
287
        {
288
            {
289
                var keyPos = 0;
290

291
                for (var i = 0; i < PSize; i++)
292
                {
293
                    var val = 0u;
294

295
                    // wrapping u32 (be)
296
                    // eg. key = { 12 34 56 78 AB CD EF GH HI JK }
297
                    // => {0x12345678, 0xABCDEFGH, 0xHIJK1234, 0x5678ABCD, ..}
298
                    for (var j = 0; j < 4; j++)
299
                    {
300
                        // wrap to the start when we reached the end.
301
                        if (keyPos >= key.Length)
302
                        {
303
                            keyPos = 0;
304
                        }
305

306
                        val = (val << 8) | key[keyPos++];
307
                    }
308

309
                    m_p[i] ^= val;
310
                }
311
            }
312

313
            {
314
                var xl = 0u;
315
                var xr = 0u;
316

317
                for (var i = 0; i < PSize; i += 2)
318
                {
319
                    (xl, xr) = EncryptBlock(xl, xr);
320

321
                    m_p[i] = xl;
322
                    m_p[i + 1] = xr;
323
                }
324

325
                for (var i = 0; i < SSize; i += 2)
326
                {
327
                    (xl, xr) = EncryptBlock(xl, xr);
328

329
                    m_s0[i] = xl;
330
                    m_s0[i + 1] = xr;
331
                }
332

333
                for (var i = 0; i < SSize; i += 2)
334
                {
335
                    (xl, xr) = EncryptBlock(xl, xr);
336

337
                    m_s1[i] = xl;
338
                    m_s1[i + 1] = xr;
339
                }
340

341
                for (var i = 0; i < SSize; i += 2)
342
                {
343
                    (xl, xr) = EncryptBlock(xl, xr);
344

345
                    m_s2[i] = xl;
346
                    m_s2[i + 1] = xr;
347
                }
348

349
                for (var i = 0; i < SSize; i += 2)
350
                {
351
                    (xl, xr) = EncryptBlock(xl, xr);
352

353
                    m_s3[i] = xl;
354
                    m_s3[i + 1] = xr;
355
                }
356
            }
357
        }
358

359
        [MethodImpl(MethodImplOptions.AggressiveInlining /* | MethodImplOptions.AggressiveOptimization */)]
360
        private uint Round(uint x)
361
        {
362
            return unchecked(
363
                ((m_s0[x >> 24] + m_s1[(byte)(x >> 16)]) ^ m_s2[(byte)(x >> 8)]) + m_s3[(byte)x]
364
            );
365
        }
366
    }
367
}
368

369
// ReSharper restore InconsistentNaming
370