Botan 3.4.0
Crypto and TLS for C&
crc24.cpp
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1/*
2* CRC24
3* (C) 1999-2007 Jack Lloyd
4* (C) 2017 [Ribose Inc](https://www.ribose.com). Performed by Krzysztof Kwiatkowski.
5*
6* Botan is released under the Simplified BSD License (see license.txt)
7*/
8
9#include <botan/internal/crc24.h>
10
11#include <botan/internal/bswap.h>
12#include <botan/internal/loadstor.h>
13
14namespace Botan {
15
16namespace {
17
18alignas(256) const uint32_t CRC24_T0[256] = {
19 0x00000000, 0x00FB4C86, 0x000DD58A, 0x00F6990C, 0x00E1E693, 0x001AAA15, 0x00EC3319, 0x00177F9F, 0x003981A1,
20 0x00C2CD27, 0x0034542B, 0x00CF18AD, 0x00D86732, 0x00232BB4, 0x00D5B2B8, 0x002EFE3E, 0x00894EC5, 0x00720243,
21 0x00849B4F, 0x007FD7C9, 0x0068A856, 0x0093E4D0, 0x00657DDC, 0x009E315A, 0x00B0CF64, 0x004B83E2, 0x00BD1AEE,
22 0x00465668, 0x005129F7, 0x00AA6571, 0x005CFC7D, 0x00A7B0FB, 0x00E9D10C, 0x00129D8A, 0x00E40486, 0x001F4800,
23 0x0008379F, 0x00F37B19, 0x0005E215, 0x00FEAE93, 0x00D050AD, 0x002B1C2B, 0x00DD8527, 0x0026C9A1, 0x0031B63E,
24 0x00CAFAB8, 0x003C63B4, 0x00C72F32, 0x00609FC9, 0x009BD34F, 0x006D4A43, 0x009606C5, 0x0081795A, 0x007A35DC,
25 0x008CACD0, 0x0077E056, 0x00591E68, 0x00A252EE, 0x0054CBE2, 0x00AF8764, 0x00B8F8FB, 0x0043B47D, 0x00B52D71,
26 0x004E61F7, 0x00D2A319, 0x0029EF9F, 0x00DF7693, 0x00243A15, 0x0033458A, 0x00C8090C, 0x003E9000, 0x00C5DC86,
27 0x00EB22B8, 0x00106E3E, 0x00E6F732, 0x001DBBB4, 0x000AC42B, 0x00F188AD, 0x000711A1, 0x00FC5D27, 0x005BEDDC,
28 0x00A0A15A, 0x00563856, 0x00AD74D0, 0x00BA0B4F, 0x004147C9, 0x00B7DEC5, 0x004C9243, 0x00626C7D, 0x009920FB,
29 0x006FB9F7, 0x0094F571, 0x00838AEE, 0x0078C668, 0x008E5F64, 0x007513E2, 0x003B7215, 0x00C03E93, 0x0036A79F,
30 0x00CDEB19, 0x00DA9486, 0x0021D800, 0x00D7410C, 0x002C0D8A, 0x0002F3B4, 0x00F9BF32, 0x000F263E, 0x00F46AB8,
31 0x00E31527, 0x001859A1, 0x00EEC0AD, 0x00158C2B, 0x00B23CD0, 0x00497056, 0x00BFE95A, 0x0044A5DC, 0x0053DA43,
32 0x00A896C5, 0x005E0FC9, 0x00A5434F, 0x008BBD71, 0x0070F1F7, 0x008668FB, 0x007D247D, 0x006A5BE2, 0x00911764,
33 0x00678E68, 0x009CC2EE, 0x00A44733, 0x005F0BB5, 0x00A992B9, 0x0052DE3F, 0x0045A1A0, 0x00BEED26, 0x0048742A,
34 0x00B338AC, 0x009DC692, 0x00668A14, 0x00901318, 0x006B5F9E, 0x007C2001, 0x00876C87, 0x0071F58B, 0x008AB90D,
35 0x002D09F6, 0x00D64570, 0x0020DC7C, 0x00DB90FA, 0x00CCEF65, 0x0037A3E3, 0x00C13AEF, 0x003A7669, 0x00148857,
36 0x00EFC4D1, 0x00195DDD, 0x00E2115B, 0x00F56EC4, 0x000E2242, 0x00F8BB4E, 0x0003F7C8, 0x004D963F, 0x00B6DAB9,
37 0x004043B5, 0x00BB0F33, 0x00AC70AC, 0x00573C2A, 0x00A1A526, 0x005AE9A0, 0x0074179E, 0x008F5B18, 0x0079C214,
38 0x00828E92, 0x0095F10D, 0x006EBD8B, 0x00982487, 0x00636801, 0x00C4D8FA, 0x003F947C, 0x00C90D70, 0x003241F6,
39 0x00253E69, 0x00DE72EF, 0x0028EBE3, 0x00D3A765, 0x00FD595B, 0x000615DD, 0x00F08CD1, 0x000BC057, 0x001CBFC8,
40 0x00E7F34E, 0x00116A42, 0x00EA26C4, 0x0076E42A, 0x008DA8AC, 0x007B31A0, 0x00807D26, 0x009702B9, 0x006C4E3F,
41 0x009AD733, 0x00619BB5, 0x004F658B, 0x00B4290D, 0x0042B001, 0x00B9FC87, 0x00AE8318, 0x0055CF9E, 0x00A35692,
42 0x00581A14, 0x00FFAAEF, 0x0004E669, 0x00F27F65, 0x000933E3, 0x001E4C7C, 0x00E500FA, 0x001399F6, 0x00E8D570,
43 0x00C62B4E, 0x003D67C8, 0x00CBFEC4, 0x0030B242, 0x0027CDDD, 0x00DC815B, 0x002A1857, 0x00D154D1, 0x009F3526,
44 0x006479A0, 0x0092E0AC, 0x0069AC2A, 0x007ED3B5, 0x00859F33, 0x0073063F, 0x00884AB9, 0x00A6B487, 0x005DF801,
45 0x00AB610D, 0x00502D8B, 0x00475214, 0x00BC1E92, 0x004A879E, 0x00B1CB18, 0x00167BE3, 0x00ED3765, 0x001BAE69,
46 0x00E0E2EF, 0x00F79D70, 0x000CD1F6, 0x00FA48FA, 0x0001047C, 0x002FFA42, 0x00D4B6C4, 0x00222FC8, 0x00D9634E,
47 0x00CE1CD1, 0x00355057, 0x00C3C95B, 0x003885DD};
48
49alignas(256) const uint32_t CRC24_T1[256] = {
50 0x00000000, 0x00488F66, 0x00901ECD, 0x00D891AB, 0x00DB711C, 0x0093FE7A, 0x004B6FD1, 0x0003E0B7, 0x00B6E338,
51 0x00FE6C5E, 0x0026FDF5, 0x006E7293, 0x006D9224, 0x00251D42, 0x00FD8CE9, 0x00B5038F, 0x006CC771, 0x00244817,
52 0x00FCD9BC, 0x00B456DA, 0x00B7B66D, 0x00FF390B, 0x0027A8A0, 0x006F27C6, 0x00DA2449, 0x0092AB2F, 0x004A3A84,
53 0x0002B5E2, 0x00015555, 0x0049DA33, 0x00914B98, 0x00D9C4FE, 0x00D88EE3, 0x00900185, 0x0048902E, 0x00001F48,
54 0x0003FFFF, 0x004B7099, 0x0093E132, 0x00DB6E54, 0x006E6DDB, 0x0026E2BD, 0x00FE7316, 0x00B6FC70, 0x00B51CC7,
55 0x00FD93A1, 0x0025020A, 0x006D8D6C, 0x00B44992, 0x00FCC6F4, 0x0024575F, 0x006CD839, 0x006F388E, 0x0027B7E8,
56 0x00FF2643, 0x00B7A925, 0x0002AAAA, 0x004A25CC, 0x0092B467, 0x00DA3B01, 0x00D9DBB6, 0x009154D0, 0x0049C57B,
57 0x00014A1D, 0x004B5141, 0x0003DE27, 0x00DB4F8C, 0x0093C0EA, 0x0090205D, 0x00D8AF3B, 0x00003E90, 0x0048B1F6,
58 0x00FDB279, 0x00B53D1F, 0x006DACB4, 0x002523D2, 0x0026C365, 0x006E4C03, 0x00B6DDA8, 0x00FE52CE, 0x00279630,
59 0x006F1956, 0x00B788FD, 0x00FF079B, 0x00FCE72C, 0x00B4684A, 0x006CF9E1, 0x00247687, 0x00917508, 0x00D9FA6E,
60 0x00016BC5, 0x0049E4A3, 0x004A0414, 0x00028B72, 0x00DA1AD9, 0x009295BF, 0x0093DFA2, 0x00DB50C4, 0x0003C16F,
61 0x004B4E09, 0x0048AEBE, 0x000021D8, 0x00D8B073, 0x00903F15, 0x00253C9A, 0x006DB3FC, 0x00B52257, 0x00FDAD31,
62 0x00FE4D86, 0x00B6C2E0, 0x006E534B, 0x0026DC2D, 0x00FF18D3, 0x00B797B5, 0x006F061E, 0x00278978, 0x002469CF,
63 0x006CE6A9, 0x00B47702, 0x00FCF864, 0x0049FBEB, 0x0001748D, 0x00D9E526, 0x00916A40, 0x00928AF7, 0x00DA0591,
64 0x0002943A, 0x004A1B5C, 0x0096A282, 0x00DE2DE4, 0x0006BC4F, 0x004E3329, 0x004DD39E, 0x00055CF8, 0x00DDCD53,
65 0x00954235, 0x002041BA, 0x0068CEDC, 0x00B05F77, 0x00F8D011, 0x00FB30A6, 0x00B3BFC0, 0x006B2E6B, 0x0023A10D,
66 0x00FA65F3, 0x00B2EA95, 0x006A7B3E, 0x0022F458, 0x002114EF, 0x00699B89, 0x00B10A22, 0x00F98544, 0x004C86CB,
67 0x000409AD, 0x00DC9806, 0x00941760, 0x0097F7D7, 0x00DF78B1, 0x0007E91A, 0x004F667C, 0x004E2C61, 0x0006A307,
68 0x00DE32AC, 0x0096BDCA, 0x00955D7D, 0x00DDD21B, 0x000543B0, 0x004DCCD6, 0x00F8CF59, 0x00B0403F, 0x0068D194,
69 0x00205EF2, 0x0023BE45, 0x006B3123, 0x00B3A088, 0x00FB2FEE, 0x0022EB10, 0x006A6476, 0x00B2F5DD, 0x00FA7ABB,
70 0x00F99A0C, 0x00B1156A, 0x006984C1, 0x00210BA7, 0x00940828, 0x00DC874E, 0x000416E5, 0x004C9983, 0x004F7934,
71 0x0007F652, 0x00DF67F9, 0x0097E89F, 0x00DDF3C3, 0x00957CA5, 0x004DED0E, 0x00056268, 0x000682DF, 0x004E0DB9,
72 0x00969C12, 0x00DE1374, 0x006B10FB, 0x00239F9D, 0x00FB0E36, 0x00B38150, 0x00B061E7, 0x00F8EE81, 0x00207F2A,
73 0x0068F04C, 0x00B134B2, 0x00F9BBD4, 0x00212A7F, 0x0069A519, 0x006A45AE, 0x0022CAC8, 0x00FA5B63, 0x00B2D405,
74 0x0007D78A, 0x004F58EC, 0x0097C947, 0x00DF4621, 0x00DCA696, 0x009429F0, 0x004CB85B, 0x0004373D, 0x00057D20,
75 0x004DF246, 0x009563ED, 0x00DDEC8B, 0x00DE0C3C, 0x0096835A, 0x004E12F1, 0x00069D97, 0x00B39E18, 0x00FB117E,
76 0x002380D5, 0x006B0FB3, 0x0068EF04, 0x00206062, 0x00F8F1C9, 0x00B07EAF, 0x0069BA51, 0x00213537, 0x00F9A49C,
77 0x00B12BFA, 0x00B2CB4D, 0x00FA442B, 0x0022D580, 0x006A5AE6, 0x00DF5969, 0x0097D60F, 0x004F47A4, 0x0007C8C2,
78 0x00042875, 0x004CA713, 0x009436B8, 0x00DCB9DE};
79
80alignas(256) const uint32_t CRC24_T2[256] = {
81 0x00000000, 0x00D70983, 0x00555F80, 0x00825603, 0x0051F286, 0x0086FB05, 0x0004AD06, 0x00D3A485, 0x0059A88B,
82 0x008EA108, 0x000CF70B, 0x00DBFE88, 0x00085A0D, 0x00DF538E, 0x005D058D, 0x008A0C0E, 0x00491C91, 0x009E1512,
83 0x001C4311, 0x00CB4A92, 0x0018EE17, 0x00CFE794, 0x004DB197, 0x009AB814, 0x0010B41A, 0x00C7BD99, 0x0045EB9A,
84 0x0092E219, 0x0041469C, 0x00964F1F, 0x0014191C, 0x00C3109F, 0x006974A4, 0x00BE7D27, 0x003C2B24, 0x00EB22A7,
85 0x00388622, 0x00EF8FA1, 0x006DD9A2, 0x00BAD021, 0x0030DC2F, 0x00E7D5AC, 0x006583AF, 0x00B28A2C, 0x00612EA9,
86 0x00B6272A, 0x00347129, 0x00E378AA, 0x00206835, 0x00F761B6, 0x007537B5, 0x00A23E36, 0x00719AB3, 0x00A69330,
87 0x0024C533, 0x00F3CCB0, 0x0079C0BE, 0x00AEC93D, 0x002C9F3E, 0x00FB96BD, 0x00283238, 0x00FF3BBB, 0x007D6DB8,
88 0x00AA643B, 0x0029A4CE, 0x00FEAD4D, 0x007CFB4E, 0x00ABF2CD, 0x00785648, 0x00AF5FCB, 0x002D09C8, 0x00FA004B,
89 0x00700C45, 0x00A705C6, 0x002553C5, 0x00F25A46, 0x0021FEC3, 0x00F6F740, 0x0074A143, 0x00A3A8C0, 0x0060B85F,
90 0x00B7B1DC, 0x0035E7DF, 0x00E2EE5C, 0x00314AD9, 0x00E6435A, 0x00641559, 0x00B31CDA, 0x003910D4, 0x00EE1957,
91 0x006C4F54, 0x00BB46D7, 0x0068E252, 0x00BFEBD1, 0x003DBDD2, 0x00EAB451, 0x0040D06A, 0x0097D9E9, 0x00158FEA,
92 0x00C28669, 0x001122EC, 0x00C62B6F, 0x00447D6C, 0x009374EF, 0x001978E1, 0x00CE7162, 0x004C2761, 0x009B2EE2,
93 0x00488A67, 0x009F83E4, 0x001DD5E7, 0x00CADC64, 0x0009CCFB, 0x00DEC578, 0x005C937B, 0x008B9AF8, 0x00583E7D,
94 0x008F37FE, 0x000D61FD, 0x00DA687E, 0x00506470, 0x00876DF3, 0x00053BF0, 0x00D23273, 0x000196F6, 0x00D69F75,
95 0x0054C976, 0x0083C0F5, 0x00A9041B, 0x007E0D98, 0x00FC5B9B, 0x002B5218, 0x00F8F69D, 0x002FFF1E, 0x00ADA91D,
96 0x007AA09E, 0x00F0AC90, 0x0027A513, 0x00A5F310, 0x0072FA93, 0x00A15E16, 0x00765795, 0x00F40196, 0x00230815,
97 0x00E0188A, 0x00371109, 0x00B5470A, 0x00624E89, 0x00B1EA0C, 0x0066E38F, 0x00E4B58C, 0x0033BC0F, 0x00B9B001,
98 0x006EB982, 0x00ECEF81, 0x003BE602, 0x00E84287, 0x003F4B04, 0x00BD1D07, 0x006A1484, 0x00C070BF, 0x0017793C,
99 0x00952F3F, 0x004226BC, 0x00918239, 0x00468BBA, 0x00C4DDB9, 0x0013D43A, 0x0099D834, 0x004ED1B7, 0x00CC87B4,
100 0x001B8E37, 0x00C82AB2, 0x001F2331, 0x009D7532, 0x004A7CB1, 0x00896C2E, 0x005E65AD, 0x00DC33AE, 0x000B3A2D,
101 0x00D89EA8, 0x000F972B, 0x008DC128, 0x005AC8AB, 0x00D0C4A5, 0x0007CD26, 0x00859B25, 0x005292A6, 0x00813623,
102 0x00563FA0, 0x00D469A3, 0x00036020, 0x0080A0D5, 0x0057A956, 0x00D5FF55, 0x0002F6D6, 0x00D15253, 0x00065BD0,
103 0x00840DD3, 0x00530450, 0x00D9085E, 0x000E01DD, 0x008C57DE, 0x005B5E5D, 0x0088FAD8, 0x005FF35B, 0x00DDA558,
104 0x000AACDB, 0x00C9BC44, 0x001EB5C7, 0x009CE3C4, 0x004BEA47, 0x00984EC2, 0x004F4741, 0x00CD1142, 0x001A18C1,
105 0x009014CF, 0x00471D4C, 0x00C54B4F, 0x001242CC, 0x00C1E649, 0x0016EFCA, 0x0094B9C9, 0x0043B04A, 0x00E9D471,
106 0x003EDDF2, 0x00BC8BF1, 0x006B8272, 0x00B826F7, 0x006F2F74, 0x00ED7977, 0x003A70F4, 0x00B07CFA, 0x00677579,
107 0x00E5237A, 0x00322AF9, 0x00E18E7C, 0x003687FF, 0x00B4D1FC, 0x0063D87F, 0x00A0C8E0, 0x0077C163, 0x00F59760,
108 0x00229EE3, 0x00F13A66, 0x002633E5, 0x00A465E6, 0x00736C65, 0x00F9606B, 0x002E69E8, 0x00AC3FEB, 0x007B3668,
109 0x00A892ED, 0x007F9B6E, 0x00FDCD6D, 0x002AC4EE};
110
111alignas(256) const uint32_t CRC24_T3[256] = {
112 0x00000000, 0x00520936, 0x00A4126C, 0x00F61B5A, 0x004825D8, 0x001A2CEE, 0x00EC37B4, 0x00BE3E82, 0x006B0636,
113 0x00390F00, 0x00CF145A, 0x009D1D6C, 0x002323EE, 0x00712AD8, 0x00873182, 0x00D538B4, 0x00D60C6C, 0x0084055A,
114 0x00721E00, 0x00201736, 0x009E29B4, 0x00CC2082, 0x003A3BD8, 0x006832EE, 0x00BD0A5A, 0x00EF036C, 0x00191836,
115 0x004B1100, 0x00F52F82, 0x00A726B4, 0x00513DEE, 0x000334D8, 0x00AC19D8, 0x00FE10EE, 0x00080BB4, 0x005A0282,
116 0x00E43C00, 0x00B63536, 0x00402E6C, 0x0012275A, 0x00C71FEE, 0x009516D8, 0x00630D82, 0x003104B4, 0x008F3A36,
117 0x00DD3300, 0x002B285A, 0x0079216C, 0x007A15B4, 0x00281C82, 0x00DE07D8, 0x008C0EEE, 0x0032306C, 0x0060395A,
118 0x00962200, 0x00C42B36, 0x00111382, 0x00431AB4, 0x00B501EE, 0x00E708D8, 0x0059365A, 0x000B3F6C, 0x00FD2436,
119 0x00AF2D00, 0x00A37F36, 0x00F17600, 0x00076D5A, 0x0055646C, 0x00EB5AEE, 0x00B953D8, 0x004F4882, 0x001D41B4,
120 0x00C87900, 0x009A7036, 0x006C6B6C, 0x003E625A, 0x00805CD8, 0x00D255EE, 0x00244EB4, 0x00764782, 0x0075735A,
121 0x00277A6C, 0x00D16136, 0x00836800, 0x003D5682, 0x006F5FB4, 0x009944EE, 0x00CB4DD8, 0x001E756C, 0x004C7C5A,
122 0x00BA6700, 0x00E86E36, 0x005650B4, 0x00045982, 0x00F242D8, 0x00A04BEE, 0x000F66EE, 0x005D6FD8, 0x00AB7482,
123 0x00F97DB4, 0x00474336, 0x00154A00, 0x00E3515A, 0x00B1586C, 0x006460D8, 0x003669EE, 0x00C072B4, 0x00927B82,
124 0x002C4500, 0x007E4C36, 0x0088576C, 0x00DA5E5A, 0x00D96A82, 0x008B63B4, 0x007D78EE, 0x002F71D8, 0x00914F5A,
125 0x00C3466C, 0x00355D36, 0x00675400, 0x00B26CB4, 0x00E06582, 0x00167ED8, 0x004477EE, 0x00FA496C, 0x00A8405A,
126 0x005E5B00, 0x000C5236, 0x0046FF6C, 0x0014F65A, 0x00E2ED00, 0x00B0E436, 0x000EDAB4, 0x005CD382, 0x00AAC8D8,
127 0x00F8C1EE, 0x002DF95A, 0x007FF06C, 0x0089EB36, 0x00DBE200, 0x0065DC82, 0x0037D5B4, 0x00C1CEEE, 0x0093C7D8,
128 0x0090F300, 0x00C2FA36, 0x0034E16C, 0x0066E85A, 0x00D8D6D8, 0x008ADFEE, 0x007CC4B4, 0x002ECD82, 0x00FBF536,
129 0x00A9FC00, 0x005FE75A, 0x000DEE6C, 0x00B3D0EE, 0x00E1D9D8, 0x0017C282, 0x0045CBB4, 0x00EAE6B4, 0x00B8EF82,
130 0x004EF4D8, 0x001CFDEE, 0x00A2C36C, 0x00F0CA5A, 0x0006D100, 0x0054D836, 0x0081E082, 0x00D3E9B4, 0x0025F2EE,
131 0x0077FBD8, 0x00C9C55A, 0x009BCC6C, 0x006DD736, 0x003FDE00, 0x003CEAD8, 0x006EE3EE, 0x0098F8B4, 0x00CAF182,
132 0x0074CF00, 0x0026C636, 0x00D0DD6C, 0x0082D45A, 0x0057ECEE, 0x0005E5D8, 0x00F3FE82, 0x00A1F7B4, 0x001FC936,
133 0x004DC000, 0x00BBDB5A, 0x00E9D26C, 0x00E5805A, 0x00B7896C, 0x00419236, 0x00139B00, 0x00ADA582, 0x00FFACB4,
134 0x0009B7EE, 0x005BBED8, 0x008E866C, 0x00DC8F5A, 0x002A9400, 0x00789D36, 0x00C6A3B4, 0x0094AA82, 0x0062B1D8,
135 0x0030B8EE, 0x00338C36, 0x00618500, 0x00979E5A, 0x00C5976C, 0x007BA9EE, 0x0029A0D8, 0x00DFBB82, 0x008DB2B4,
136 0x00588A00, 0x000A8336, 0x00FC986C, 0x00AE915A, 0x0010AFD8, 0x0042A6EE, 0x00B4BDB4, 0x00E6B482, 0x00499982,
137 0x001B90B4, 0x00ED8BEE, 0x00BF82D8, 0x0001BC5A, 0x0053B56C, 0x00A5AE36, 0x00F7A700, 0x00229FB4, 0x00709682,
138 0x00868DD8, 0x00D484EE, 0x006ABA6C, 0x0038B35A, 0x00CEA800, 0x009CA136, 0x009F95EE, 0x00CD9CD8, 0x003B8782,
139 0x00698EB4, 0x00D7B036, 0x0085B900, 0x0073A25A, 0x0021AB6C, 0x00F493D8, 0x00A69AEE, 0x005081B4, 0x00028882,
140 0x00BCB600, 0x00EEBF36, 0x0018A46C, 0x004AAD5A};
141
142inline uint32_t process8(uint32_t crc, uint8_t data) {
143 return (crc >> 8) ^ CRC24_T0[get_byte<3>(crc) ^ data];
144}
145
146inline uint32_t process32(uint32_t crc, uint32_t word) {
147 const uint32_t sum = crc ^ word;
148
149 return CRC24_T3[get_byte<3>(sum)] ^ CRC24_T2[get_byte<2>(sum)] ^ CRC24_T1[get_byte<1>(sum)] ^
150 CRC24_T0[get_byte<0>(sum)];
151}
152} // namespace
153
154std::unique_ptr<HashFunction> CRC24::copy_state() const {
155 return std::make_unique<CRC24>(*this);
156}
157
158/*
159* Update a CRC24 Checksum
160*
161* Implementation uses Slicing-by-N algorithm described in
162* "Novel Table Lookup-Based Algorithms for High-Performance
163* CRC Generation", by M.Kounavis.
164*
165* This algorithm uses 4 precomputed look-up tables. First
166* table T0 is computed same way as in a method proposed
167* by D. Sarwate (1988). Then T_1, T2 and T3 are computed
168* in following way:
169*
170* T1[j] = (T0[j] >> 8) ^ T0[ T0[j] & 0xFF ]
171* T2[j] = (T1[j] >> 8) ^ T0[ T1[j] & 0xFF ]
172* T3[j] = (T2[j] >> 8) ^ T0[ T2[j] & 0xFF ]
173*
174*/
175void CRC24::add_data(std::span<const uint8_t> input) {
176 uint32_t tmp = m_crc;
177
178 // Input is word aligned if WA & input == 0
179 static const uint8_t WA = sizeof(size_t) - 1;
180
181 // Ensure input is word aligned before processing in parallel
182 for(; !input.empty() && (reinterpret_cast<uintptr_t>(input.data()) & WA); input = input.last(input.size() - 1)) {
183 tmp = process8(tmp, input.front());
184 }
185
186 while(input.size() >= 16) {
187 uint32_t d[4];
188 load_le(d, input.data(), 4);
189 tmp = process32(tmp, d[0]);
190 tmp = process32(tmp, d[1]);
191 tmp = process32(tmp, d[2]);
192 tmp = process32(tmp, d[3]);
193
194 input = input.last(input.size() - 16);
195 }
196
197 for(; !input.empty(); input = input.last(input.size() - 1)) {
198 tmp = process8(tmp, input.front());
199 }
200
201 m_crc = tmp;
202}
203
204/*
205* Finalize a CRC24 Checksum
206*/
207void CRC24::final_result(std::span<uint8_t> output) {
208 output[0] = get_byte<3>(m_crc);
209 output[1] = get_byte<2>(m_crc);
210 output[2] = get_byte<1>(m_crc);
211 clear();
212}
213
214} // namespace Botan
Botan::CRC24::clear
void clear() override
Definition crc24.h:31
Botan::CRC24::copy_state
std::unique_ptr< HashFunction > copy_state() const override
Definition crc24.cpp:154
Botan::load_le
constexpr auto load_le(ParamTs &&... params)
Definition loadstor.h:462
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