Botan 3.6.1
Crypto and TLS for C&
crc24.cpp
Go to the documentation of this file.
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/loadstor.h>
12
13namespace Botan {
14
15namespace {
16
17alignas(256) const uint32_t CRC24_T0[256] = {
18 0x00000000, 0x00FB4C86, 0x000DD58A, 0x00F6990C, 0x00E1E693, 0x001AAA15, 0x00EC3319, 0x00177F9F, 0x003981A1,
19 0x00C2CD27, 0x0034542B, 0x00CF18AD, 0x00D86732, 0x00232BB4, 0x00D5B2B8, 0x002EFE3E, 0x00894EC5, 0x00720243,
20 0x00849B4F, 0x007FD7C9, 0x0068A856, 0x0093E4D0, 0x00657DDC, 0x009E315A, 0x00B0CF64, 0x004B83E2, 0x00BD1AEE,
21 0x00465668, 0x005129F7, 0x00AA6571, 0x005CFC7D, 0x00A7B0FB, 0x00E9D10C, 0x00129D8A, 0x00E40486, 0x001F4800,
22 0x0008379F, 0x00F37B19, 0x0005E215, 0x00FEAE93, 0x00D050AD, 0x002B1C2B, 0x00DD8527, 0x0026C9A1, 0x0031B63E,
23 0x00CAFAB8, 0x003C63B4, 0x00C72F32, 0x00609FC9, 0x009BD34F, 0x006D4A43, 0x009606C5, 0x0081795A, 0x007A35DC,
24 0x008CACD0, 0x0077E056, 0x00591E68, 0x00A252EE, 0x0054CBE2, 0x00AF8764, 0x00B8F8FB, 0x0043B47D, 0x00B52D71,
25 0x004E61F7, 0x00D2A319, 0x0029EF9F, 0x00DF7693, 0x00243A15, 0x0033458A, 0x00C8090C, 0x003E9000, 0x00C5DC86,
26 0x00EB22B8, 0x00106E3E, 0x00E6F732, 0x001DBBB4, 0x000AC42B, 0x00F188AD, 0x000711A1, 0x00FC5D27, 0x005BEDDC,
27 0x00A0A15A, 0x00563856, 0x00AD74D0, 0x00BA0B4F, 0x004147C9, 0x00B7DEC5, 0x004C9243, 0x00626C7D, 0x009920FB,
28 0x006FB9F7, 0x0094F571, 0x00838AEE, 0x0078C668, 0x008E5F64, 0x007513E2, 0x003B7215, 0x00C03E93, 0x0036A79F,
29 0x00CDEB19, 0x00DA9486, 0x0021D800, 0x00D7410C, 0x002C0D8A, 0x0002F3B4, 0x00F9BF32, 0x000F263E, 0x00F46AB8,
30 0x00E31527, 0x001859A1, 0x00EEC0AD, 0x00158C2B, 0x00B23CD0, 0x00497056, 0x00BFE95A, 0x0044A5DC, 0x0053DA43,
31 0x00A896C5, 0x005E0FC9, 0x00A5434F, 0x008BBD71, 0x0070F1F7, 0x008668FB, 0x007D247D, 0x006A5BE2, 0x00911764,
32 0x00678E68, 0x009CC2EE, 0x00A44733, 0x005F0BB5, 0x00A992B9, 0x0052DE3F, 0x0045A1A0, 0x00BEED26, 0x0048742A,
33 0x00B338AC, 0x009DC692, 0x00668A14, 0x00901318, 0x006B5F9E, 0x007C2001, 0x00876C87, 0x0071F58B, 0x008AB90D,
34 0x002D09F6, 0x00D64570, 0x0020DC7C, 0x00DB90FA, 0x00CCEF65, 0x0037A3E3, 0x00C13AEF, 0x003A7669, 0x00148857,
35 0x00EFC4D1, 0x00195DDD, 0x00E2115B, 0x00F56EC4, 0x000E2242, 0x00F8BB4E, 0x0003F7C8, 0x004D963F, 0x00B6DAB9,
36 0x004043B5, 0x00BB0F33, 0x00AC70AC, 0x00573C2A, 0x00A1A526, 0x005AE9A0, 0x0074179E, 0x008F5B18, 0x0079C214,
37 0x00828E92, 0x0095F10D, 0x006EBD8B, 0x00982487, 0x00636801, 0x00C4D8FA, 0x003F947C, 0x00C90D70, 0x003241F6,
38 0x00253E69, 0x00DE72EF, 0x0028EBE3, 0x00D3A765, 0x00FD595B, 0x000615DD, 0x00F08CD1, 0x000BC057, 0x001CBFC8,
39 0x00E7F34E, 0x00116A42, 0x00EA26C4, 0x0076E42A, 0x008DA8AC, 0x007B31A0, 0x00807D26, 0x009702B9, 0x006C4E3F,
40 0x009AD733, 0x00619BB5, 0x004F658B, 0x00B4290D, 0x0042B001, 0x00B9FC87, 0x00AE8318, 0x0055CF9E, 0x00A35692,
41 0x00581A14, 0x00FFAAEF, 0x0004E669, 0x00F27F65, 0x000933E3, 0x001E4C7C, 0x00E500FA, 0x001399F6, 0x00E8D570,
42 0x00C62B4E, 0x003D67C8, 0x00CBFEC4, 0x0030B242, 0x0027CDDD, 0x00DC815B, 0x002A1857, 0x00D154D1, 0x009F3526,
43 0x006479A0, 0x0092E0AC, 0x0069AC2A, 0x007ED3B5, 0x00859F33, 0x0073063F, 0x00884AB9, 0x00A6B487, 0x005DF801,
44 0x00AB610D, 0x00502D8B, 0x00475214, 0x00BC1E92, 0x004A879E, 0x00B1CB18, 0x00167BE3, 0x00ED3765, 0x001BAE69,
45 0x00E0E2EF, 0x00F79D70, 0x000CD1F6, 0x00FA48FA, 0x0001047C, 0x002FFA42, 0x00D4B6C4, 0x00222FC8, 0x00D9634E,
46 0x00CE1CD1, 0x00355057, 0x00C3C95B, 0x003885DD};
47
48alignas(256) const uint32_t CRC24_T1[256] = {
49 0x00000000, 0x00488F66, 0x00901ECD, 0x00D891AB, 0x00DB711C, 0x0093FE7A, 0x004B6FD1, 0x0003E0B7, 0x00B6E338,
50 0x00FE6C5E, 0x0026FDF5, 0x006E7293, 0x006D9224, 0x00251D42, 0x00FD8CE9, 0x00B5038F, 0x006CC771, 0x00244817,
51 0x00FCD9BC, 0x00B456DA, 0x00B7B66D, 0x00FF390B, 0x0027A8A0, 0x006F27C6, 0x00DA2449, 0x0092AB2F, 0x004A3A84,
52 0x0002B5E2, 0x00015555, 0x0049DA33, 0x00914B98, 0x00D9C4FE, 0x00D88EE3, 0x00900185, 0x0048902E, 0x00001F48,
53 0x0003FFFF, 0x004B7099, 0x0093E132, 0x00DB6E54, 0x006E6DDB, 0x0026E2BD, 0x00FE7316, 0x00B6FC70, 0x00B51CC7,
54 0x00FD93A1, 0x0025020A, 0x006D8D6C, 0x00B44992, 0x00FCC6F4, 0x0024575F, 0x006CD839, 0x006F388E, 0x0027B7E8,
55 0x00FF2643, 0x00B7A925, 0x0002AAAA, 0x004A25CC, 0x0092B467, 0x00DA3B01, 0x00D9DBB6, 0x009154D0, 0x0049C57B,
56 0x00014A1D, 0x004B5141, 0x0003DE27, 0x00DB4F8C, 0x0093C0EA, 0x0090205D, 0x00D8AF3B, 0x00003E90, 0x0048B1F6,
57 0x00FDB279, 0x00B53D1F, 0x006DACB4, 0x002523D2, 0x0026C365, 0x006E4C03, 0x00B6DDA8, 0x00FE52CE, 0x00279630,
58 0x006F1956, 0x00B788FD, 0x00FF079B, 0x00FCE72C, 0x00B4684A, 0x006CF9E1, 0x00247687, 0x00917508, 0x00D9FA6E,
59 0x00016BC5, 0x0049E4A3, 0x004A0414, 0x00028B72, 0x00DA1AD9, 0x009295BF, 0x0093DFA2, 0x00DB50C4, 0x0003C16F,
60 0x004B4E09, 0x0048AEBE, 0x000021D8, 0x00D8B073, 0x00903F15, 0x00253C9A, 0x006DB3FC, 0x00B52257, 0x00FDAD31,
61 0x00FE4D86, 0x00B6C2E0, 0x006E534B, 0x0026DC2D, 0x00FF18D3, 0x00B797B5, 0x006F061E, 0x00278978, 0x002469CF,
62 0x006CE6A9, 0x00B47702, 0x00FCF864, 0x0049FBEB, 0x0001748D, 0x00D9E526, 0x00916A40, 0x00928AF7, 0x00DA0591,
63 0x0002943A, 0x004A1B5C, 0x0096A282, 0x00DE2DE4, 0x0006BC4F, 0x004E3329, 0x004DD39E, 0x00055CF8, 0x00DDCD53,
64 0x00954235, 0x002041BA, 0x0068CEDC, 0x00B05F77, 0x00F8D011, 0x00FB30A6, 0x00B3BFC0, 0x006B2E6B, 0x0023A10D,
65 0x00FA65F3, 0x00B2EA95, 0x006A7B3E, 0x0022F458, 0x002114EF, 0x00699B89, 0x00B10A22, 0x00F98544, 0x004C86CB,
66 0x000409AD, 0x00DC9806, 0x00941760, 0x0097F7D7, 0x00DF78B1, 0x0007E91A, 0x004F667C, 0x004E2C61, 0x0006A307,
67 0x00DE32AC, 0x0096BDCA, 0x00955D7D, 0x00DDD21B, 0x000543B0, 0x004DCCD6, 0x00F8CF59, 0x00B0403F, 0x0068D194,
68 0x00205EF2, 0x0023BE45, 0x006B3123, 0x00B3A088, 0x00FB2FEE, 0x0022EB10, 0x006A6476, 0x00B2F5DD, 0x00FA7ABB,
69 0x00F99A0C, 0x00B1156A, 0x006984C1, 0x00210BA7, 0x00940828, 0x00DC874E, 0x000416E5, 0x004C9983, 0x004F7934,
70 0x0007F652, 0x00DF67F9, 0x0097E89F, 0x00DDF3C3, 0x00957CA5, 0x004DED0E, 0x00056268, 0x000682DF, 0x004E0DB9,
71 0x00969C12, 0x00DE1374, 0x006B10FB, 0x00239F9D, 0x00FB0E36, 0x00B38150, 0x00B061E7, 0x00F8EE81, 0x00207F2A,
72 0x0068F04C, 0x00B134B2, 0x00F9BBD4, 0x00212A7F, 0x0069A519, 0x006A45AE, 0x0022CAC8, 0x00FA5B63, 0x00B2D405,
73 0x0007D78A, 0x004F58EC, 0x0097C947, 0x00DF4621, 0x00DCA696, 0x009429F0, 0x004CB85B, 0x0004373D, 0x00057D20,
74 0x004DF246, 0x009563ED, 0x00DDEC8B, 0x00DE0C3C, 0x0096835A, 0x004E12F1, 0x00069D97, 0x00B39E18, 0x00FB117E,
75 0x002380D5, 0x006B0FB3, 0x0068EF04, 0x00206062, 0x00F8F1C9, 0x00B07EAF, 0x0069BA51, 0x00213537, 0x00F9A49C,
76 0x00B12BFA, 0x00B2CB4D, 0x00FA442B, 0x0022D580, 0x006A5AE6, 0x00DF5969, 0x0097D60F, 0x004F47A4, 0x0007C8C2,
77 0x00042875, 0x004CA713, 0x009436B8, 0x00DCB9DE};
78
79alignas(256) const uint32_t CRC24_T2[256] = {
80 0x00000000, 0x00D70983, 0x00555F80, 0x00825603, 0x0051F286, 0x0086FB05, 0x0004AD06, 0x00D3A485, 0x0059A88B,
81 0x008EA108, 0x000CF70B, 0x00DBFE88, 0x00085A0D, 0x00DF538E, 0x005D058D, 0x008A0C0E, 0x00491C91, 0x009E1512,
82 0x001C4311, 0x00CB4A92, 0x0018EE17, 0x00CFE794, 0x004DB197, 0x009AB814, 0x0010B41A, 0x00C7BD99, 0x0045EB9A,
83 0x0092E219, 0x0041469C, 0x00964F1F, 0x0014191C, 0x00C3109F, 0x006974A4, 0x00BE7D27, 0x003C2B24, 0x00EB22A7,
84 0x00388622, 0x00EF8FA1, 0x006DD9A2, 0x00BAD021, 0x0030DC2F, 0x00E7D5AC, 0x006583AF, 0x00B28A2C, 0x00612EA9,
85 0x00B6272A, 0x00347129, 0x00E378AA, 0x00206835, 0x00F761B6, 0x007537B5, 0x00A23E36, 0x00719AB3, 0x00A69330,
86 0x0024C533, 0x00F3CCB0, 0x0079C0BE, 0x00AEC93D, 0x002C9F3E, 0x00FB96BD, 0x00283238, 0x00FF3BBB, 0x007D6DB8,
87 0x00AA643B, 0x0029A4CE, 0x00FEAD4D, 0x007CFB4E, 0x00ABF2CD, 0x00785648, 0x00AF5FCB, 0x002D09C8, 0x00FA004B,
88 0x00700C45, 0x00A705C6, 0x002553C5, 0x00F25A46, 0x0021FEC3, 0x00F6F740, 0x0074A143, 0x00A3A8C0, 0x0060B85F,
89 0x00B7B1DC, 0x0035E7DF, 0x00E2EE5C, 0x00314AD9, 0x00E6435A, 0x00641559, 0x00B31CDA, 0x003910D4, 0x00EE1957,
90 0x006C4F54, 0x00BB46D7, 0x0068E252, 0x00BFEBD1, 0x003DBDD2, 0x00EAB451, 0x0040D06A, 0x0097D9E9, 0x00158FEA,
91 0x00C28669, 0x001122EC, 0x00C62B6F, 0x00447D6C, 0x009374EF, 0x001978E1, 0x00CE7162, 0x004C2761, 0x009B2EE2,
92 0x00488A67, 0x009F83E4, 0x001DD5E7, 0x00CADC64, 0x0009CCFB, 0x00DEC578, 0x005C937B, 0x008B9AF8, 0x00583E7D,
93 0x008F37FE, 0x000D61FD, 0x00DA687E, 0x00506470, 0x00876DF3, 0x00053BF0, 0x00D23273, 0x000196F6, 0x00D69F75,
94 0x0054C976, 0x0083C0F5, 0x00A9041B, 0x007E0D98, 0x00FC5B9B, 0x002B5218, 0x00F8F69D, 0x002FFF1E, 0x00ADA91D,
95 0x007AA09E, 0x00F0AC90, 0x0027A513, 0x00A5F310, 0x0072FA93, 0x00A15E16, 0x00765795, 0x00F40196, 0x00230815,
96 0x00E0188A, 0x00371109, 0x00B5470A, 0x00624E89, 0x00B1EA0C, 0x0066E38F, 0x00E4B58C, 0x0033BC0F, 0x00B9B001,
97 0x006EB982, 0x00ECEF81, 0x003BE602, 0x00E84287, 0x003F4B04, 0x00BD1D07, 0x006A1484, 0x00C070BF, 0x0017793C,
98 0x00952F3F, 0x004226BC, 0x00918239, 0x00468BBA, 0x00C4DDB9, 0x0013D43A, 0x0099D834, 0x004ED1B7, 0x00CC87B4,
99 0x001B8E37, 0x00C82AB2, 0x001F2331, 0x009D7532, 0x004A7CB1, 0x00896C2E, 0x005E65AD, 0x00DC33AE, 0x000B3A2D,
100 0x00D89EA8, 0x000F972B, 0x008DC128, 0x005AC8AB, 0x00D0C4A5, 0x0007CD26, 0x00859B25, 0x005292A6, 0x00813623,
101 0x00563FA0, 0x00D469A3, 0x00036020, 0x0080A0D5, 0x0057A956, 0x00D5FF55, 0x0002F6D6, 0x00D15253, 0x00065BD0,
102 0x00840DD3, 0x00530450, 0x00D9085E, 0x000E01DD, 0x008C57DE, 0x005B5E5D, 0x0088FAD8, 0x005FF35B, 0x00DDA558,
103 0x000AACDB, 0x00C9BC44, 0x001EB5C7, 0x009CE3C4, 0x004BEA47, 0x00984EC2, 0x004F4741, 0x00CD1142, 0x001A18C1,
104 0x009014CF, 0x00471D4C, 0x00C54B4F, 0x001242CC, 0x00C1E649, 0x0016EFCA, 0x0094B9C9, 0x0043B04A, 0x00E9D471,
105 0x003EDDF2, 0x00BC8BF1, 0x006B8272, 0x00B826F7, 0x006F2F74, 0x00ED7977, 0x003A70F4, 0x00B07CFA, 0x00677579,
106 0x00E5237A, 0x00322AF9, 0x00E18E7C, 0x003687FF, 0x00B4D1FC, 0x0063D87F, 0x00A0C8E0, 0x0077C163, 0x00F59760,
107 0x00229EE3, 0x00F13A66, 0x002633E5, 0x00A465E6, 0x00736C65, 0x00F9606B, 0x002E69E8, 0x00AC3FEB, 0x007B3668,
108 0x00A892ED, 0x007F9B6E, 0x00FDCD6D, 0x002AC4EE};
109
110alignas(256) const uint32_t CRC24_T3[256] = {
111 0x00000000, 0x00520936, 0x00A4126C, 0x00F61B5A, 0x004825D8, 0x001A2CEE, 0x00EC37B4, 0x00BE3E82, 0x006B0636,
112 0x00390F00, 0x00CF145A, 0x009D1D6C, 0x002323EE, 0x00712AD8, 0x00873182, 0x00D538B4, 0x00D60C6C, 0x0084055A,
113 0x00721E00, 0x00201736, 0x009E29B4, 0x00CC2082, 0x003A3BD8, 0x006832EE, 0x00BD0A5A, 0x00EF036C, 0x00191836,
114 0x004B1100, 0x00F52F82, 0x00A726B4, 0x00513DEE, 0x000334D8, 0x00AC19D8, 0x00FE10EE, 0x00080BB4, 0x005A0282,
115 0x00E43C00, 0x00B63536, 0x00402E6C, 0x0012275A, 0x00C71FEE, 0x009516D8, 0x00630D82, 0x003104B4, 0x008F3A36,
116 0x00DD3300, 0x002B285A, 0x0079216C, 0x007A15B4, 0x00281C82, 0x00DE07D8, 0x008C0EEE, 0x0032306C, 0x0060395A,
117 0x00962200, 0x00C42B36, 0x00111382, 0x00431AB4, 0x00B501EE, 0x00E708D8, 0x0059365A, 0x000B3F6C, 0x00FD2436,
118 0x00AF2D00, 0x00A37F36, 0x00F17600, 0x00076D5A, 0x0055646C, 0x00EB5AEE, 0x00B953D8, 0x004F4882, 0x001D41B4,
119 0x00C87900, 0x009A7036, 0x006C6B6C, 0x003E625A, 0x00805CD8, 0x00D255EE, 0x00244EB4, 0x00764782, 0x0075735A,
120 0x00277A6C, 0x00D16136, 0x00836800, 0x003D5682, 0x006F5FB4, 0x009944EE, 0x00CB4DD8, 0x001E756C, 0x004C7C5A,
121 0x00BA6700, 0x00E86E36, 0x005650B4, 0x00045982, 0x00F242D8, 0x00A04BEE, 0x000F66EE, 0x005D6FD8, 0x00AB7482,
122 0x00F97DB4, 0x00474336, 0x00154A00, 0x00E3515A, 0x00B1586C, 0x006460D8, 0x003669EE, 0x00C072B4, 0x00927B82,
123 0x002C4500, 0x007E4C36, 0x0088576C, 0x00DA5E5A, 0x00D96A82, 0x008B63B4, 0x007D78EE, 0x002F71D8, 0x00914F5A,
124 0x00C3466C, 0x00355D36, 0x00675400, 0x00B26CB4, 0x00E06582, 0x00167ED8, 0x004477EE, 0x00FA496C, 0x00A8405A,
125 0x005E5B00, 0x000C5236, 0x0046FF6C, 0x0014F65A, 0x00E2ED00, 0x00B0E436, 0x000EDAB4, 0x005CD382, 0x00AAC8D8,
126 0x00F8C1EE, 0x002DF95A, 0x007FF06C, 0x0089EB36, 0x00DBE200, 0x0065DC82, 0x0037D5B4, 0x00C1CEEE, 0x0093C7D8,
127 0x0090F300, 0x00C2FA36, 0x0034E16C, 0x0066E85A, 0x00D8D6D8, 0x008ADFEE, 0x007CC4B4, 0x002ECD82, 0x00FBF536,
128 0x00A9FC00, 0x005FE75A, 0x000DEE6C, 0x00B3D0EE, 0x00E1D9D8, 0x0017C282, 0x0045CBB4, 0x00EAE6B4, 0x00B8EF82,
129 0x004EF4D8, 0x001CFDEE, 0x00A2C36C, 0x00F0CA5A, 0x0006D100, 0x0054D836, 0x0081E082, 0x00D3E9B4, 0x0025F2EE,
130 0x0077FBD8, 0x00C9C55A, 0x009BCC6C, 0x006DD736, 0x003FDE00, 0x003CEAD8, 0x006EE3EE, 0x0098F8B4, 0x00CAF182,
131 0x0074CF00, 0x0026C636, 0x00D0DD6C, 0x0082D45A, 0x0057ECEE, 0x0005E5D8, 0x00F3FE82, 0x00A1F7B4, 0x001FC936,
132 0x004DC000, 0x00BBDB5A, 0x00E9D26C, 0x00E5805A, 0x00B7896C, 0x00419236, 0x00139B00, 0x00ADA582, 0x00FFACB4,
133 0x0009B7EE, 0x005BBED8, 0x008E866C, 0x00DC8F5A, 0x002A9400, 0x00789D36, 0x00C6A3B4, 0x0094AA82, 0x0062B1D8,
134 0x0030B8EE, 0x00338C36, 0x00618500, 0x00979E5A, 0x00C5976C, 0x007BA9EE, 0x0029A0D8, 0x00DFBB82, 0x008DB2B4,
135 0x00588A00, 0x000A8336, 0x00FC986C, 0x00AE915A, 0x0010AFD8, 0x0042A6EE, 0x00B4BDB4, 0x00E6B482, 0x00499982,
136 0x001B90B4, 0x00ED8BEE, 0x00BF82D8, 0x0001BC5A, 0x0053B56C, 0x00A5AE36, 0x00F7A700, 0x00229FB4, 0x00709682,
137 0x00868DD8, 0x00D484EE, 0x006ABA6C, 0x0038B35A, 0x00CEA800, 0x009CA136, 0x009F95EE, 0x00CD9CD8, 0x003B8782,
138 0x00698EB4, 0x00D7B036, 0x0085B900, 0x0073A25A, 0x0021AB6C, 0x00F493D8, 0x00A69AEE, 0x005081B4, 0x00028882,
139 0x00BCB600, 0x00EEBF36, 0x0018A46C, 0x004AAD5A};
140
141inline uint32_t process8(uint32_t crc, uint8_t data) {
142 return (crc >> 8) ^ CRC24_T0[get_byte<3>(crc) ^ data];
143}
144
145inline uint32_t process32(uint32_t crc, uint32_t word) {
146 const uint32_t sum = crc ^ word;
147
148 return CRC24_T3[get_byte<3>(sum)] ^ CRC24_T2[get_byte<2>(sum)] ^ CRC24_T1[get_byte<1>(sum)] ^
149 CRC24_T0[get_byte<0>(sum)];
150}
151} // namespace
152
153std::unique_ptr<HashFunction> CRC24::copy_state() const {
154 return std::make_unique<CRC24>(*this);
155}
156
157/*
158* Update a CRC24 Checksum
159*
160* Implementation uses Slicing-by-N algorithm described in
161* "Novel Table Lookup-Based Algorithms for High-Performance
162* CRC Generation", by M.Kounavis.
163*
164* This algorithm uses 4 precomputed look-up tables. First
165* table T0 is computed same way as in a method proposed
166* by D. Sarwate (1988). Then T_1, T2 and T3 are computed
167* in following way:
168*
169* T1[j] = (T0[j] >> 8) ^ T0[ T0[j] & 0xFF ]
170* T2[j] = (T1[j] >> 8) ^ T0[ T1[j] & 0xFF ]
171* T3[j] = (T2[j] >> 8) ^ T0[ T2[j] & 0xFF ]
172*
173*/
174void CRC24::add_data(std::span<const uint8_t> input) {
175 uint32_t tmp = m_crc;
176
177 // Input is word aligned if WA & input == 0
178 static const uint8_t WA = sizeof(size_t) - 1;
179
180 // Ensure input is word aligned before processing in parallel
181 for(; !input.empty() && (reinterpret_cast<uintptr_t>(input.data()) & WA); input = input.last(input.size() - 1)) {
182 tmp = process8(tmp, input.front());
183 }
184
185 while(input.size() >= 16) {
186 uint32_t d[4];
187 load_le(d, input.data(), 4);
188 tmp = process32(tmp, d[0]);
189 tmp = process32(tmp, d[1]);
190 tmp = process32(tmp, d[2]);
191 tmp = process32(tmp, d[3]);
192
193 input = input.last(input.size() - 16);
194 }
195
196 for(; !input.empty(); input = input.last(input.size() - 1)) {
197 tmp = process8(tmp, input.front());
198 }
199
200 m_crc = tmp;
201}
202
203/*
204* Finalize a CRC24 Checksum
205*/
206void CRC24::final_result(std::span<uint8_t> output) {
207 output[0] = get_byte<3>(m_crc);
208 output[1] = get_byte<2>(m_crc);
209 output[2] = get_byte<1>(m_crc);
210 clear();
211}
212
213} // 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:153
Botan::get_byte
constexpr uint8_t get_byte(T input)
Definition loadstor.h:75
Botan::load_le
constexpr auto load_le(ParamTs &&... params)
Definition loadstor.h:521
Generated by doxygen 1.12.0