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1 /*
2  * Copyright (c) 2014 Grzegorz Kostka (kostka.grzegorz@gmail.com)
3  * All rights reserved.
4  *
5  * Based on FreeBSD.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * - Redistributions of source code must retain the above copyright
12  *   notice, this list of conditions and the following disclaimer.
13  * - Redistributions in binary form must reproduce the above copyright
14  *   notice, this list of conditions and the following disclaimer in the
15  *   documentation and/or other materials provided with the distribution.
16  * - The name of the author may not be used to endorse or promote products
17  *   derived from this software without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29  */
30
31 /** @addtogroup lwext4
32  * @{
33  */
34 /**
35  * @file  ext4_crc32c.c
36  * @brief Crc32c routine. Taken from FreeBSD kernel.
37  */
38
39 #include "ext4_config.h"
40 #include "ext4_crc32c.h"
41
42 /* */
43 /* CRC LOOKUP TABLE */
44 /* ================ */
45 /* The following CRC lookup table was generated automagically */
46 /* by the Rocksoft^tm Model CRC Algorithm Table Generation */
47 /* Program V1.0 using the following model parameters: */
48 /* */
49 /* Width : 4 bytes. */
50 /* Poly : 0x1EDC6F41L */
51 /* Reverse : TRUE. */
52 /* */
53 /* For more information on the Rocksoft^tm Model CRC Algorithm, */
54 /* see the document titled "A Painless Guide to CRC Error */
55 /* Detection Algorithms" by Ross Williams */
56 /* (ross@guest.adelaide.edu.au.). This document is likely to be */
57 /* in the FTP archive "ftp.adelaide.edu.au/pub/rocksoft". */
58 /* */
59 static const uint32_t crc32Table[256] = {
60     0x00000000L, 0xF26B8303L, 0xE13B70F7L, 0x1350F3F4L, 0xC79A971FL,
61     0x35F1141CL, 0x26A1E7E8L, 0xD4CA64EBL, 0x8AD958CFL, 0x78B2DBCCL,
62     0x6BE22838L, 0x9989AB3BL, 0x4D43CFD0L, 0xBF284CD3L, 0xAC78BF27L,
63     0x5E133C24L, 0x105EC76FL, 0xE235446CL, 0xF165B798L, 0x030E349BL,
64     0xD7C45070L, 0x25AFD373L, 0x36FF2087L, 0xC494A384L, 0x9A879FA0L,
65     0x68EC1CA3L, 0x7BBCEF57L, 0x89D76C54L, 0x5D1D08BFL, 0xAF768BBCL,
66     0xBC267848L, 0x4E4DFB4BL, 0x20BD8EDEL, 0xD2D60DDDL, 0xC186FE29L,
67     0x33ED7D2AL, 0xE72719C1L, 0x154C9AC2L, 0x061C6936L, 0xF477EA35L,
68     0xAA64D611L, 0x580F5512L, 0x4B5FA6E6L, 0xB93425E5L, 0x6DFE410EL,
69     0x9F95C20DL, 0x8CC531F9L, 0x7EAEB2FAL, 0x30E349B1L, 0xC288CAB2L,
70     0xD1D83946L, 0x23B3BA45L, 0xF779DEAEL, 0x05125DADL, 0x1642AE59L,
71     0xE4292D5AL, 0xBA3A117EL, 0x4851927DL, 0x5B016189L, 0xA96AE28AL,
72     0x7DA08661L, 0x8FCB0562L, 0x9C9BF696L, 0x6EF07595L, 0x417B1DBCL,
73     0xB3109EBFL, 0xA0406D4BL, 0x522BEE48L, 0x86E18AA3L, 0x748A09A0L,
74     0x67DAFA54L, 0x95B17957L, 0xCBA24573L, 0x39C9C670L, 0x2A993584L,
75     0xD8F2B687L, 0x0C38D26CL, 0xFE53516FL, 0xED03A29BL, 0x1F682198L,
76     0x5125DAD3L, 0xA34E59D0L, 0xB01EAA24L, 0x42752927L, 0x96BF4DCCL,
77     0x64D4CECFL, 0x77843D3BL, 0x85EFBE38L, 0xDBFC821CL, 0x2997011FL,
78     0x3AC7F2EBL, 0xC8AC71E8L, 0x1C661503L, 0xEE0D9600L, 0xFD5D65F4L,
79     0x0F36E6F7L, 0x61C69362L, 0x93AD1061L, 0x80FDE395L, 0x72966096L,
80     0xA65C047DL, 0x5437877EL, 0x4767748AL, 0xB50CF789L, 0xEB1FCBADL,
81     0x197448AEL, 0x0A24BB5AL, 0xF84F3859L, 0x2C855CB2L, 0xDEEEDFB1L,
82     0xCDBE2C45L, 0x3FD5AF46L, 0x7198540DL, 0x83F3D70EL, 0x90A324FAL,
83     0x62C8A7F9L, 0xB602C312L, 0x44694011L, 0x5739B3E5L, 0xA55230E6L,
84     0xFB410CC2L, 0x092A8FC1L, 0x1A7A7C35L, 0xE811FF36L, 0x3CDB9BDDL,
85     0xCEB018DEL, 0xDDE0EB2AL, 0x2F8B6829L, 0x82F63B78L, 0x709DB87BL,
86     0x63CD4B8FL, 0x91A6C88CL, 0x456CAC67L, 0xB7072F64L, 0xA457DC90L,
87     0x563C5F93L, 0x082F63B7L, 0xFA44E0B4L, 0xE9141340L, 0x1B7F9043L,
88     0xCFB5F4A8L, 0x3DDE77ABL, 0x2E8E845FL, 0xDCE5075CL, 0x92A8FC17L,
89     0x60C37F14L, 0x73938CE0L, 0x81F80FE3L, 0x55326B08L, 0xA759E80BL,
90     0xB4091BFFL, 0x466298FCL, 0x1871A4D8L, 0xEA1A27DBL, 0xF94AD42FL,
91     0x0B21572CL, 0xDFEB33C7L, 0x2D80B0C4L, 0x3ED04330L, 0xCCBBC033L,
92     0xA24BB5A6L, 0x502036A5L, 0x4370C551L, 0xB11B4652L, 0x65D122B9L,
93     0x97BAA1BAL, 0x84EA524EL, 0x7681D14DL, 0x2892ED69L, 0xDAF96E6AL,
94     0xC9A99D9EL, 0x3BC21E9DL, 0xEF087A76L, 0x1D63F975L, 0x0E330A81L,
95     0xFC588982L, 0xB21572C9L, 0x407EF1CAL, 0x532E023EL, 0xA145813DL,
96     0x758FE5D6L, 0x87E466D5L, 0x94B49521L, 0x66DF1622L, 0x38CC2A06L,
97     0xCAA7A905L, 0xD9F75AF1L, 0x2B9CD9F2L, 0xFF56BD19L, 0x0D3D3E1AL,
98     0x1E6DCDEEL, 0xEC064EEDL, 0xC38D26C4L, 0x31E6A5C7L, 0x22B65633L,
99     0xD0DDD530L, 0x0417B1DBL, 0xF67C32D8L, 0xE52CC12CL, 0x1747422FL,
100     0x49547E0BL, 0xBB3FFD08L, 0xA86F0EFCL, 0x5A048DFFL, 0x8ECEE914L,
101     0x7CA56A17L, 0x6FF599E3L, 0x9D9E1AE0L, 0xD3D3E1ABL, 0x21B862A8L,
102     0x32E8915CL, 0xC083125FL, 0x144976B4L, 0xE622F5B7L, 0xF5720643L,
103     0x07198540L, 0x590AB964L, 0xAB613A67L, 0xB831C993L, 0x4A5A4A90L,
104     0x9E902E7BL, 0x6CFBAD78L, 0x7FAB5E8CL, 0x8DC0DD8FL, 0xE330A81AL,
105     0x115B2B19L, 0x020BD8EDL, 0xF0605BEEL, 0x24AA3F05L, 0xD6C1BC06L,
106     0xC5914FF2L, 0x37FACCF1L, 0x69E9F0D5L, 0x9B8273D6L, 0x88D28022L,
107     0x7AB90321L, 0xAE7367CAL, 0x5C18E4C9L, 0x4F48173DL, 0xBD23943EL,
108     0xF36E6F75L, 0x0105EC76L, 0x12551F82L, 0xE03E9C81L, 0x34F4F86AL,
109     0xC69F7B69L, 0xD5CF889DL, 0x27A40B9EL, 0x79B737BAL, 0x8BDCB4B9L,
110     0x988C474DL, 0x6AE7C44EL, 0xBE2DA0A5L, 0x4C4623A6L, 0x5F16D052L,
111     0xAD7D5351L};
112
113 uint32_t ext4_crc32c(uint32_t crc, const void *buffer, uint32_t length)
114 {
115     const uint8_t *p = buffer;
116
117     while (length--)
118         crc = crc32Table[(crc ^ *p++) & 0xff] ^ (crc >> 8);
119
120     return crc;
121 }
122
123 /**
124  * @}
125  */