Botan 2.19.3
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/crc24.h>
10#include <botan/loadstor.h>
11#include <botan/bswap.h>
12
13namespace Botan {
14
15namespace {
16
17alignas(64) const uint32_t CRC24_T0[256] = {
18 0x00000000, 0x00FB4C86, 0x000DD58A, 0x00F6990C, 0x00E1E693, 0x001AAA15, 0x00EC3319,
19 0x00177F9F, 0x003981A1, 0x00C2CD27, 0x0034542B, 0x00CF18AD, 0x00D86732, 0x00232BB4,
20 0x00D5B2B8, 0x002EFE3E, 0x00894EC5, 0x00720243, 0x00849B4F, 0x007FD7C9, 0x0068A856,
21 0x0093E4D0, 0x00657DDC, 0x009E315A, 0x00B0CF64, 0x004B83E2, 0x00BD1AEE, 0x00465668,
22 0x005129F7, 0x00AA6571, 0x005CFC7D, 0x00A7B0FB, 0x00E9D10C, 0x00129D8A, 0x00E40486,
23 0x001F4800, 0x0008379F, 0x00F37B19, 0x0005E215, 0x00FEAE93, 0x00D050AD, 0x002B1C2B,
24 0x00DD8527, 0x0026C9A1, 0x0031B63E, 0x00CAFAB8, 0x003C63B4, 0x00C72F32, 0x00609FC9,
25 0x009BD34F, 0x006D4A43, 0x009606C5, 0x0081795A, 0x007A35DC, 0x008CACD0, 0x0077E056,
26 0x00591E68, 0x00A252EE, 0x0054CBE2, 0x00AF8764, 0x00B8F8FB, 0x0043B47D, 0x00B52D71,
27 0x004E61F7, 0x00D2A319, 0x0029EF9F, 0x00DF7693, 0x00243A15, 0x0033458A, 0x00C8090C,
28 0x003E9000, 0x00C5DC86, 0x00EB22B8, 0x00106E3E, 0x00E6F732, 0x001DBBB4, 0x000AC42B,
29 0x00F188AD, 0x000711A1, 0x00FC5D27, 0x005BEDDC, 0x00A0A15A, 0x00563856, 0x00AD74D0,
30 0x00BA0B4F, 0x004147C9, 0x00B7DEC5, 0x004C9243, 0x00626C7D, 0x009920FB, 0x006FB9F7,
31 0x0094F571, 0x00838AEE, 0x0078C668, 0x008E5F64, 0x007513E2, 0x003B7215, 0x00C03E93,
32 0x0036A79F, 0x00CDEB19, 0x00DA9486, 0x0021D800, 0x00D7410C, 0x002C0D8A, 0x0002F3B4,
33 0x00F9BF32, 0x000F263E, 0x00F46AB8, 0x00E31527, 0x001859A1, 0x00EEC0AD, 0x00158C2B,
34 0x00B23CD0, 0x00497056, 0x00BFE95A, 0x0044A5DC, 0x0053DA43, 0x00A896C5, 0x005E0FC9,
35 0x00A5434F, 0x008BBD71, 0x0070F1F7, 0x008668FB, 0x007D247D, 0x006A5BE2, 0x00911764,
36 0x00678E68, 0x009CC2EE, 0x00A44733, 0x005F0BB5, 0x00A992B9, 0x0052DE3F, 0x0045A1A0,
37 0x00BEED26, 0x0048742A, 0x00B338AC, 0x009DC692, 0x00668A14, 0x00901318, 0x006B5F9E,
38 0x007C2001, 0x00876C87, 0x0071F58B, 0x008AB90D, 0x002D09F6, 0x00D64570, 0x0020DC7C,
39 0x00DB90FA, 0x00CCEF65, 0x0037A3E3, 0x00C13AEF, 0x003A7669, 0x00148857, 0x00EFC4D1,
40 0x00195DDD, 0x00E2115B, 0x00F56EC4, 0x000E2242, 0x00F8BB4E, 0x0003F7C8, 0x004D963F,
41 0x00B6DAB9, 0x004043B5, 0x00BB0F33, 0x00AC70AC, 0x00573C2A, 0x00A1A526, 0x005AE9A0,
42 0x0074179E, 0x008F5B18, 0x0079C214, 0x00828E92, 0x0095F10D, 0x006EBD8B, 0x00982487,
43 0x00636801, 0x00C4D8FA, 0x003F947C, 0x00C90D70, 0x003241F6, 0x00253E69, 0x00DE72EF,
44 0x0028EBE3, 0x00D3A765, 0x00FD595B, 0x000615DD, 0x00F08CD1, 0x000BC057, 0x001CBFC8,
45 0x00E7F34E, 0x00116A42, 0x00EA26C4, 0x0076E42A, 0x008DA8AC, 0x007B31A0, 0x00807D26,
46 0x009702B9, 0x006C4E3F, 0x009AD733, 0x00619BB5, 0x004F658B, 0x00B4290D, 0x0042B001,
47 0x00B9FC87, 0x00AE8318, 0x0055CF9E, 0x00A35692, 0x00581A14, 0x00FFAAEF, 0x0004E669,
48 0x00F27F65, 0x000933E3, 0x001E4C7C, 0x00E500FA, 0x001399F6, 0x00E8D570, 0x00C62B4E,
49 0x003D67C8, 0x00CBFEC4, 0x0030B242, 0x0027CDDD, 0x00DC815B, 0x002A1857, 0x00D154D1,
50 0x009F3526, 0x006479A0, 0x0092E0AC, 0x0069AC2A, 0x007ED3B5, 0x00859F33, 0x0073063F,
51 0x00884AB9, 0x00A6B487, 0x005DF801, 0x00AB610D, 0x00502D8B, 0x00475214, 0x00BC1E92,
52 0x004A879E, 0x00B1CB18, 0x00167BE3, 0x00ED3765, 0x001BAE69, 0x00E0E2EF, 0x00F79D70,
53 0x000CD1F6, 0x00FA48FA, 0x0001047C, 0x002FFA42, 0x00D4B6C4, 0x00222FC8, 0x00D9634E,
54 0x00CE1CD1, 0x00355057, 0x00C3C95B, 0x003885DD };
55
56alignas(64) const uint32_t CRC24_T1[256] = {
57 0x00000000, 0x00488F66, 0x00901ECD, 0x00D891AB, 0x00DB711C, 0x0093FE7A, 0x004B6FD1,
58 0x0003E0B7, 0x00B6E338, 0x00FE6C5E, 0x0026FDF5, 0x006E7293, 0x006D9224, 0x00251D42,
59 0x00FD8CE9, 0x00B5038F, 0x006CC771, 0x00244817, 0x00FCD9BC, 0x00B456DA, 0x00B7B66D,
60 0x00FF390B, 0x0027A8A0, 0x006F27C6, 0x00DA2449, 0x0092AB2F, 0x004A3A84, 0x0002B5E2,
61 0x00015555, 0x0049DA33, 0x00914B98, 0x00D9C4FE, 0x00D88EE3, 0x00900185, 0x0048902E,
62 0x00001F48, 0x0003FFFF, 0x004B7099, 0x0093E132, 0x00DB6E54, 0x006E6DDB, 0x0026E2BD,
63 0x00FE7316, 0x00B6FC70, 0x00B51CC7, 0x00FD93A1, 0x0025020A, 0x006D8D6C, 0x00B44992,
64 0x00FCC6F4, 0x0024575F, 0x006CD839, 0x006F388E, 0x0027B7E8, 0x00FF2643, 0x00B7A925,
65 0x0002AAAA, 0x004A25CC, 0x0092B467, 0x00DA3B01, 0x00D9DBB6, 0x009154D0, 0x0049C57B,
66 0x00014A1D, 0x004B5141, 0x0003DE27, 0x00DB4F8C, 0x0093C0EA, 0x0090205D, 0x00D8AF3B,
67 0x00003E90, 0x0048B1F6, 0x00FDB279, 0x00B53D1F, 0x006DACB4, 0x002523D2, 0x0026C365,
68 0x006E4C03, 0x00B6DDA8, 0x00FE52CE, 0x00279630, 0x006F1956, 0x00B788FD, 0x00FF079B,
69 0x00FCE72C, 0x00B4684A, 0x006CF9E1, 0x00247687, 0x00917508, 0x00D9FA6E, 0x00016BC5,
70 0x0049E4A3, 0x004A0414, 0x00028B72, 0x00DA1AD9, 0x009295BF, 0x0093DFA2, 0x00DB50C4,
71 0x0003C16F, 0x004B4E09, 0x0048AEBE, 0x000021D8, 0x00D8B073, 0x00903F15, 0x00253C9A,
72 0x006DB3FC, 0x00B52257, 0x00FDAD31, 0x00FE4D86, 0x00B6C2E0, 0x006E534B, 0x0026DC2D,
73 0x00FF18D3, 0x00B797B5, 0x006F061E, 0x00278978, 0x002469CF, 0x006CE6A9, 0x00B47702,
74 0x00FCF864, 0x0049FBEB, 0x0001748D, 0x00D9E526, 0x00916A40, 0x00928AF7, 0x00DA0591,
75 0x0002943A, 0x004A1B5C, 0x0096A282, 0x00DE2DE4, 0x0006BC4F, 0x004E3329, 0x004DD39E,
76 0x00055CF8, 0x00DDCD53, 0x00954235, 0x002041BA, 0x0068CEDC, 0x00B05F77, 0x00F8D011,
77 0x00FB30A6, 0x00B3BFC0, 0x006B2E6B, 0x0023A10D, 0x00FA65F3, 0x00B2EA95, 0x006A7B3E,
78 0x0022F458, 0x002114EF, 0x00699B89, 0x00B10A22, 0x00F98544, 0x004C86CB, 0x000409AD,
79 0x00DC9806, 0x00941760, 0x0097F7D7, 0x00DF78B1, 0x0007E91A, 0x004F667C, 0x004E2C61,
80 0x0006A307, 0x00DE32AC, 0x0096BDCA, 0x00955D7D, 0x00DDD21B, 0x000543B0, 0x004DCCD6,
81 0x00F8CF59, 0x00B0403F, 0x0068D194, 0x00205EF2, 0x0023BE45, 0x006B3123, 0x00B3A088,
82 0x00FB2FEE, 0x0022EB10, 0x006A6476, 0x00B2F5DD, 0x00FA7ABB, 0x00F99A0C, 0x00B1156A,
83 0x006984C1, 0x00210BA7, 0x00940828, 0x00DC874E, 0x000416E5, 0x004C9983, 0x004F7934,
84 0x0007F652, 0x00DF67F9, 0x0097E89F, 0x00DDF3C3, 0x00957CA5, 0x004DED0E, 0x00056268,
85 0x000682DF, 0x004E0DB9, 0x00969C12, 0x00DE1374, 0x006B10FB, 0x00239F9D, 0x00FB0E36,
86 0x00B38150, 0x00B061E7, 0x00F8EE81, 0x00207F2A, 0x0068F04C, 0x00B134B2, 0x00F9BBD4,
87 0x00212A7F, 0x0069A519, 0x006A45AE, 0x0022CAC8, 0x00FA5B63, 0x00B2D405, 0x0007D78A,
88 0x004F58EC, 0x0097C947, 0x00DF4621, 0x00DCA696, 0x009429F0, 0x004CB85B, 0x0004373D,
89 0x00057D20, 0x004DF246, 0x009563ED, 0x00DDEC8B, 0x00DE0C3C, 0x0096835A, 0x004E12F1,
90 0x00069D97, 0x00B39E18, 0x00FB117E, 0x002380D5, 0x006B0FB3, 0x0068EF04, 0x00206062,
91 0x00F8F1C9, 0x00B07EAF, 0x0069BA51, 0x00213537, 0x00F9A49C, 0x00B12BFA, 0x00B2CB4D,
92 0x00FA442B, 0x0022D580, 0x006A5AE6, 0x00DF5969, 0x0097D60F, 0x004F47A4, 0x0007C8C2,
93 0x00042875, 0x004CA713, 0x009436B8, 0x00DCB9DE };
94
95alignas(64) const uint32_t CRC24_T2[256] = {
96 0x00000000, 0x00D70983, 0x00555F80, 0x00825603, 0x0051F286, 0x0086FB05, 0x0004AD06,
97 0x00D3A485, 0x0059A88B, 0x008EA108, 0x000CF70B, 0x00DBFE88, 0x00085A0D, 0x00DF538E,
98 0x005D058D, 0x008A0C0E, 0x00491C91, 0x009E1512, 0x001C4311, 0x00CB4A92, 0x0018EE17,
99 0x00CFE794, 0x004DB197, 0x009AB814, 0x0010B41A, 0x00C7BD99, 0x0045EB9A, 0x0092E219,
100 0x0041469C, 0x00964F1F, 0x0014191C, 0x00C3109F, 0x006974A4, 0x00BE7D27, 0x003C2B24,
101 0x00EB22A7, 0x00388622, 0x00EF8FA1, 0x006DD9A2, 0x00BAD021, 0x0030DC2F, 0x00E7D5AC,
102 0x006583AF, 0x00B28A2C, 0x00612EA9, 0x00B6272A, 0x00347129, 0x00E378AA, 0x00206835,
103 0x00F761B6, 0x007537B5, 0x00A23E36, 0x00719AB3, 0x00A69330, 0x0024C533, 0x00F3CCB0,
104 0x0079C0BE, 0x00AEC93D, 0x002C9F3E, 0x00FB96BD, 0x00283238, 0x00FF3BBB, 0x007D6DB8,
105 0x00AA643B, 0x0029A4CE, 0x00FEAD4D, 0x007CFB4E, 0x00ABF2CD, 0x00785648, 0x00AF5FCB,
106 0x002D09C8, 0x00FA004B, 0x00700C45, 0x00A705C6, 0x002553C5, 0x00F25A46, 0x0021FEC3,
107 0x00F6F740, 0x0074A143, 0x00A3A8C0, 0x0060B85F, 0x00B7B1DC, 0x0035E7DF, 0x00E2EE5C,
108 0x00314AD9, 0x00E6435A, 0x00641559, 0x00B31CDA, 0x003910D4, 0x00EE1957, 0x006C4F54,
109 0x00BB46D7, 0x0068E252, 0x00BFEBD1, 0x003DBDD2, 0x00EAB451, 0x0040D06A, 0x0097D9E9,
110 0x00158FEA, 0x00C28669, 0x001122EC, 0x00C62B6F, 0x00447D6C, 0x009374EF, 0x001978E1,
111 0x00CE7162, 0x004C2761, 0x009B2EE2, 0x00488A67, 0x009F83E4, 0x001DD5E7, 0x00CADC64,
112 0x0009CCFB, 0x00DEC578, 0x005C937B, 0x008B9AF8, 0x00583E7D, 0x008F37FE, 0x000D61FD,
113 0x00DA687E, 0x00506470, 0x00876DF3, 0x00053BF0, 0x00D23273, 0x000196F6, 0x00D69F75,
114 0x0054C976, 0x0083C0F5, 0x00A9041B, 0x007E0D98, 0x00FC5B9B, 0x002B5218, 0x00F8F69D,
115 0x002FFF1E, 0x00ADA91D, 0x007AA09E, 0x00F0AC90, 0x0027A513, 0x00A5F310, 0x0072FA93,
116 0x00A15E16, 0x00765795, 0x00F40196, 0x00230815, 0x00E0188A, 0x00371109, 0x00B5470A,
117 0x00624E89, 0x00B1EA0C, 0x0066E38F, 0x00E4B58C, 0x0033BC0F, 0x00B9B001, 0x006EB982,
118 0x00ECEF81, 0x003BE602, 0x00E84287, 0x003F4B04, 0x00BD1D07, 0x006A1484, 0x00C070BF,
119 0x0017793C, 0x00952F3F, 0x004226BC, 0x00918239, 0x00468BBA, 0x00C4DDB9, 0x0013D43A,
120 0x0099D834, 0x004ED1B7, 0x00CC87B4, 0x001B8E37, 0x00C82AB2, 0x001F2331, 0x009D7532,
121 0x004A7CB1, 0x00896C2E, 0x005E65AD, 0x00DC33AE, 0x000B3A2D, 0x00D89EA8, 0x000F972B,
122 0x008DC128, 0x005AC8AB, 0x00D0C4A5, 0x0007CD26, 0x00859B25, 0x005292A6, 0x00813623,
123 0x00563FA0, 0x00D469A3, 0x00036020, 0x0080A0D5, 0x0057A956, 0x00D5FF55, 0x0002F6D6,
124 0x00D15253, 0x00065BD0, 0x00840DD3, 0x00530450, 0x00D9085E, 0x000E01DD, 0x008C57DE,
125 0x005B5E5D, 0x0088FAD8, 0x005FF35B, 0x00DDA558, 0x000AACDB, 0x00C9BC44, 0x001EB5C7,
126 0x009CE3C4, 0x004BEA47, 0x00984EC2, 0x004F4741, 0x00CD1142, 0x001A18C1, 0x009014CF,
127 0x00471D4C, 0x00C54B4F, 0x001242CC, 0x00C1E649, 0x0016EFCA, 0x0094B9C9, 0x0043B04A,
128 0x00E9D471, 0x003EDDF2, 0x00BC8BF1, 0x006B8272, 0x00B826F7, 0x006F2F74, 0x00ED7977,
129 0x003A70F4, 0x00B07CFA, 0x00677579, 0x00E5237A, 0x00322AF9, 0x00E18E7C, 0x003687FF,
130 0x00B4D1FC, 0x0063D87F, 0x00A0C8E0, 0x0077C163, 0x00F59760, 0x00229EE3, 0x00F13A66,
131 0x002633E5, 0x00A465E6, 0x00736C65, 0x00F9606B, 0x002E69E8, 0x00AC3FEB, 0x007B3668,
132 0x00A892ED, 0x007F9B6E, 0x00FDCD6D, 0x002AC4EE };
133
134alignas(64) const uint32_t CRC24_T3[256] = {
135 0x00000000, 0x00520936, 0x00A4126C, 0x00F61B5A, 0x004825D8, 0x001A2CEE, 0x00EC37B4,
136 0x00BE3E82, 0x006B0636, 0x00390F00, 0x00CF145A, 0x009D1D6C, 0x002323EE, 0x00712AD8,
137 0x00873182, 0x00D538B4, 0x00D60C6C, 0x0084055A, 0x00721E00, 0x00201736, 0x009E29B4,
138 0x00CC2082, 0x003A3BD8, 0x006832EE, 0x00BD0A5A, 0x00EF036C, 0x00191836, 0x004B1100,
139 0x00F52F82, 0x00A726B4, 0x00513DEE, 0x000334D8, 0x00AC19D8, 0x00FE10EE, 0x00080BB4,
140 0x005A0282, 0x00E43C00, 0x00B63536, 0x00402E6C, 0x0012275A, 0x00C71FEE, 0x009516D8,
141 0x00630D82, 0x003104B4, 0x008F3A36, 0x00DD3300, 0x002B285A, 0x0079216C, 0x007A15B4,
142 0x00281C82, 0x00DE07D8, 0x008C0EEE, 0x0032306C, 0x0060395A, 0x00962200, 0x00C42B36,
143 0x00111382, 0x00431AB4, 0x00B501EE, 0x00E708D8, 0x0059365A, 0x000B3F6C, 0x00FD2436,
144 0x00AF2D00, 0x00A37F36, 0x00F17600, 0x00076D5A, 0x0055646C, 0x00EB5AEE, 0x00B953D8,
145 0x004F4882, 0x001D41B4, 0x00C87900, 0x009A7036, 0x006C6B6C, 0x003E625A, 0x00805CD8,
146 0x00D255EE, 0x00244EB4, 0x00764782, 0x0075735A, 0x00277A6C, 0x00D16136, 0x00836800,
147 0x003D5682, 0x006F5FB4, 0x009944EE, 0x00CB4DD8, 0x001E756C, 0x004C7C5A, 0x00BA6700,
148 0x00E86E36, 0x005650B4, 0x00045982, 0x00F242D8, 0x00A04BEE, 0x000F66EE, 0x005D6FD8,
149 0x00AB7482, 0x00F97DB4, 0x00474336, 0x00154A00, 0x00E3515A, 0x00B1586C, 0x006460D8,
150 0x003669EE, 0x00C072B4, 0x00927B82, 0x002C4500, 0x007E4C36, 0x0088576C, 0x00DA5E5A,
151 0x00D96A82, 0x008B63B4, 0x007D78EE, 0x002F71D8, 0x00914F5A, 0x00C3466C, 0x00355D36,
152 0x00675400, 0x00B26CB4, 0x00E06582, 0x00167ED8, 0x004477EE, 0x00FA496C, 0x00A8405A,
153 0x005E5B00, 0x000C5236, 0x0046FF6C, 0x0014F65A, 0x00E2ED00, 0x00B0E436, 0x000EDAB4,
154 0x005CD382, 0x00AAC8D8, 0x00F8C1EE, 0x002DF95A, 0x007FF06C, 0x0089EB36, 0x00DBE200,
155 0x0065DC82, 0x0037D5B4, 0x00C1CEEE, 0x0093C7D8, 0x0090F300, 0x00C2FA36, 0x0034E16C,
156 0x0066E85A, 0x00D8D6D8, 0x008ADFEE, 0x007CC4B4, 0x002ECD82, 0x00FBF536, 0x00A9FC00,
157 0x005FE75A, 0x000DEE6C, 0x00B3D0EE, 0x00E1D9D8, 0x0017C282, 0x0045CBB4, 0x00EAE6B4,
158 0x00B8EF82, 0x004EF4D8, 0x001CFDEE, 0x00A2C36C, 0x00F0CA5A, 0x0006D100, 0x0054D836,
159 0x0081E082, 0x00D3E9B4, 0x0025F2EE, 0x0077FBD8, 0x00C9C55A, 0x009BCC6C, 0x006DD736,
160 0x003FDE00, 0x003CEAD8, 0x006EE3EE, 0x0098F8B4, 0x00CAF182, 0x0074CF00, 0x0026C636,
161 0x00D0DD6C, 0x0082D45A, 0x0057ECEE, 0x0005E5D8, 0x00F3FE82, 0x00A1F7B4, 0x001FC936,
162 0x004DC000, 0x00BBDB5A, 0x00E9D26C, 0x00E5805A, 0x00B7896C, 0x00419236, 0x00139B00,
163 0x00ADA582, 0x00FFACB4, 0x0009B7EE, 0x005BBED8, 0x008E866C, 0x00DC8F5A, 0x002A9400,
164 0x00789D36, 0x00C6A3B4, 0x0094AA82, 0x0062B1D8, 0x0030B8EE, 0x00338C36, 0x00618500,
165 0x00979E5A, 0x00C5976C, 0x007BA9EE, 0x0029A0D8, 0x00DFBB82, 0x008DB2B4, 0x00588A00,
166 0x000A8336, 0x00FC986C, 0x00AE915A, 0x0010AFD8, 0x0042A6EE, 0x00B4BDB4, 0x00E6B482,
167 0x00499982, 0x001B90B4, 0x00ED8BEE, 0x00BF82D8, 0x0001BC5A, 0x0053B56C, 0x00A5AE36,
168 0x00F7A700, 0x00229FB4, 0x00709682, 0x00868DD8, 0x00D484EE, 0x006ABA6C, 0x0038B35A,
169 0x00CEA800, 0x009CA136, 0x009F95EE, 0x00CD9CD8, 0x003B8782, 0x00698EB4, 0x00D7B036,
170 0x0085B900, 0x0073A25A, 0x0021AB6C, 0x00F493D8, 0x00A69AEE, 0x005081B4, 0x00028882,
171 0x00BCB600, 0x00EEBF36, 0x0018A46C, 0x004AAD5A };
172
173inline uint32_t process8(uint32_t crc, uint8_t data)
174 {
175 return (crc >> 8) ^ CRC24_T0[(crc & 0xff) ^ data];
176 }
177
178inline uint32_t process32(uint32_t crc, uint32_t word)
179 {
180 crc ^= word;
181 crc = CRC24_T3[(crc >> 0) & 0xff]
182 ^ CRC24_T2[(crc >> 8) & 0xff]
183 ^ CRC24_T1[(crc >> 16) & 0xff]
184 ^ CRC24_T0[(crc >> 24) & 0xff];
185 return crc;
186 }
187}
188
189std::unique_ptr<HashFunction> CRC24::copy_state() const
190 {
191 return std::unique_ptr<HashFunction>(new CRC24(*this));
192 }
193
194/*
195* Update a CRC24 Checksum
196*
197* Implementation uses Slicing-by-N algorithm described in
198* "Novel Table Lookup-Based Algorithms for High-Performance
199* CRC Generation", by M.Kounavis.
200*
201* This algorithm uses 4 precomputed look-up tables. First
202* table T0 is computed same way as in a method proposed
203* by D. Sarwate (1988). Then T_1, T2 and T3 are computed
204* in following way:
205*
206* T1[j] = (T0[j] >> 8) ^ T0[ T0[j] & 0xFF ]
207* T2[j] = (T1[j] >> 8) ^ T0[ T1[j] & 0xFF ]
208* T3[j] = (T2[j] >> 8) ^ T0[ T2[j] & 0xFF ]
209*
210*/
211void CRC24::add_data(const uint8_t input[], size_t length)
212 {
213 uint32_t d[4];
214 uint32_t tmp = m_crc;
215
216 // Input is word aligned if WA & input == 0
217 static const uint8_t WA = (BOTAN_MP_WORD_BITS/8) - 1;
218
219 // Ensure input is word aligned before processing in parallel
220 for(;length && (reinterpret_cast<uintptr_t>(input) & WA); length--)
221 tmp = process8(tmp, *input++);
222
223 while(length >= 16)
224 {
225 load_le(d, input, 4);
226 tmp = process32(tmp, d[0]);
227 tmp = process32(tmp, d[1]);
228 tmp = process32(tmp, d[2]);
229 tmp = process32(tmp, d[3]);
230
231 input += 16;
232 length -= 16;
233 }
234
235 while(length--)
236 tmp = process8(tmp, *input++);
237
238 m_crc = tmp & 0xffffff;
239 }
240
241/*
242* Finalize a CRC24 Checksum
243*/
244void CRC24::final_result(uint8_t output[])
245 {
246 output[0] = get_byte(3, m_crc);
247 output[1] = get_byte(2, m_crc);
248 output[2] = get_byte(1, m_crc);
249 clear();
250 }
251
252}
void clear() override
Definition crc24.h:29
std::unique_ptr< HashFunction > copy_state() const override
Definition crc24.cpp:189
T load_le(const uint8_t in[], size_t off)
Definition loadstor.h:123
constexpr uint8_t get_byte(size_t byte_num, T input)
Definition loadstor.h:41