1/*
2 * CRC32C
3 *@Article{castagnoli-crc,
4 * author =       { Guy Castagnoli and Stefan Braeuer and Martin Herrman},
5 * title =        {{Optimization of Cyclic Redundancy-Check Codes with 24
6 *                 and 32 Parity Bits}},
7 * journal =      IEEE Transactions on Communication,
8 * year =         {1993},
9 * volume =       {41},
10 * number =       {6},
11 * pages =        {},
12 * month =        {June},
13 *}
14 * Used by the iSCSI driver, possibly others, and derived from the
15 * the iscsi-crc.c module of the linux-iscsi driver at
16 * http://linux-iscsi.sourceforge.net.
17 *
18 * Following the example of lib/crc32, this function is intended to be
19 * flexible and useful for all users.  Modules that currently have their
20 * own crc32c, but hopefully may be able to use this one are:
21 *  net/sctp (please add all your doco to here if you change to
22 *            use this one!)
23 *  <endoflist>
24 *
25 * Copyright (c) 2004 Cisco Systems, Inc.
26 *
27 * This program is free software; you can redistribute it and/or modify it
28 * under the terms of the GNU General Public License as published by the Free
29 * Software Foundation; either version 2 of the License, or (at your option)
30 * any later version.
31 *
32 */
33#include <inttypes.h>
34
35#include "crc32c.h"
36
37/*
38 * This is the CRC-32C table
39 * Generated with:
40 * width = 32 bits
41 * poly = 0x1EDC6F41
42 * reflect input bytes = true
43 * reflect output bytes = true
44 */
45
46static const uint32_t crc32c_table[256] = {
47	0x00000000L, 0xF26B8303L, 0xE13B70F7L, 0x1350F3F4L,
48	0xC79A971FL, 0x35F1141CL, 0x26A1E7E8L, 0xD4CA64EBL,
49	0x8AD958CFL, 0x78B2DBCCL, 0x6BE22838L, 0x9989AB3BL,
50	0x4D43CFD0L, 0xBF284CD3L, 0xAC78BF27L, 0x5E133C24L,
51	0x105EC76FL, 0xE235446CL, 0xF165B798L, 0x030E349BL,
52	0xD7C45070L, 0x25AFD373L, 0x36FF2087L, 0xC494A384L,
53	0x9A879FA0L, 0x68EC1CA3L, 0x7BBCEF57L, 0x89D76C54L,
54	0x5D1D08BFL, 0xAF768BBCL, 0xBC267848L, 0x4E4DFB4BL,
55	0x20BD8EDEL, 0xD2D60DDDL, 0xC186FE29L, 0x33ED7D2AL,
56	0xE72719C1L, 0x154C9AC2L, 0x061C6936L, 0xF477EA35L,
57	0xAA64D611L, 0x580F5512L, 0x4B5FA6E6L, 0xB93425E5L,
58	0x6DFE410EL, 0x9F95C20DL, 0x8CC531F9L, 0x7EAEB2FAL,
59	0x30E349B1L, 0xC288CAB2L, 0xD1D83946L, 0x23B3BA45L,
60	0xF779DEAEL, 0x05125DADL, 0x1642AE59L, 0xE4292D5AL,
61	0xBA3A117EL, 0x4851927DL, 0x5B016189L, 0xA96AE28AL,
62	0x7DA08661L, 0x8FCB0562L, 0x9C9BF696L, 0x6EF07595L,
63	0x417B1DBCL, 0xB3109EBFL, 0xA0406D4BL, 0x522BEE48L,
64	0x86E18AA3L, 0x748A09A0L, 0x67DAFA54L, 0x95B17957L,
65	0xCBA24573L, 0x39C9C670L, 0x2A993584L, 0xD8F2B687L,
66	0x0C38D26CL, 0xFE53516FL, 0xED03A29BL, 0x1F682198L,
67	0x5125DAD3L, 0xA34E59D0L, 0xB01EAA24L, 0x42752927L,
68	0x96BF4DCCL, 0x64D4CECFL, 0x77843D3BL, 0x85EFBE38L,
69	0xDBFC821CL, 0x2997011FL, 0x3AC7F2EBL, 0xC8AC71E8L,
70	0x1C661503L, 0xEE0D9600L, 0xFD5D65F4L, 0x0F36E6F7L,
71	0x61C69362L, 0x93AD1061L, 0x80FDE395L, 0x72966096L,
72	0xA65C047DL, 0x5437877EL, 0x4767748AL, 0xB50CF789L,
73	0xEB1FCBADL, 0x197448AEL, 0x0A24BB5AL, 0xF84F3859L,
74	0x2C855CB2L, 0xDEEEDFB1L, 0xCDBE2C45L, 0x3FD5AF46L,
75	0x7198540DL, 0x83F3D70EL, 0x90A324FAL, 0x62C8A7F9L,
76	0xB602C312L, 0x44694011L, 0x5739B3E5L, 0xA55230E6L,
77	0xFB410CC2L, 0x092A8FC1L, 0x1A7A7C35L, 0xE811FF36L,
78	0x3CDB9BDDL, 0xCEB018DEL, 0xDDE0EB2AL, 0x2F8B6829L,
79	0x82F63B78L, 0x709DB87BL, 0x63CD4B8FL, 0x91A6C88CL,
80	0x456CAC67L, 0xB7072F64L, 0xA457DC90L, 0x563C5F93L,
81	0x082F63B7L, 0xFA44E0B4L, 0xE9141340L, 0x1B7F9043L,
82	0xCFB5F4A8L, 0x3DDE77ABL, 0x2E8E845FL, 0xDCE5075CL,
83	0x92A8FC17L, 0x60C37F14L, 0x73938CE0L, 0x81F80FE3L,
84	0x55326B08L, 0xA759E80BL, 0xB4091BFFL, 0x466298FCL,
85	0x1871A4D8L, 0xEA1A27DBL, 0xF94AD42FL, 0x0B21572CL,
86	0xDFEB33C7L, 0x2D80B0C4L, 0x3ED04330L, 0xCCBBC033L,
87	0xA24BB5A6L, 0x502036A5L, 0x4370C551L, 0xB11B4652L,
88	0x65D122B9L, 0x97BAA1BAL, 0x84EA524EL, 0x7681D14DL,
89	0x2892ED69L, 0xDAF96E6AL, 0xC9A99D9EL, 0x3BC21E9DL,
90	0xEF087A76L, 0x1D63F975L, 0x0E330A81L, 0xFC588982L,
91	0xB21572C9L, 0x407EF1CAL, 0x532E023EL, 0xA145813DL,
92	0x758FE5D6L, 0x87E466D5L, 0x94B49521L, 0x66DF1622L,
93	0x38CC2A06L, 0xCAA7A905L, 0xD9F75AF1L, 0x2B9CD9F2L,
94	0xFF56BD19L, 0x0D3D3E1AL, 0x1E6DCDEEL, 0xEC064EEDL,
95	0xC38D26C4L, 0x31E6A5C7L, 0x22B65633L, 0xD0DDD530L,
96	0x0417B1DBL, 0xF67C32D8L, 0xE52CC12CL, 0x1747422FL,
97	0x49547E0BL, 0xBB3FFD08L, 0xA86F0EFCL, 0x5A048DFFL,
98	0x8ECEE914L, 0x7CA56A17L, 0x6FF599E3L, 0x9D9E1AE0L,
99	0xD3D3E1ABL, 0x21B862A8L, 0x32E8915CL, 0xC083125FL,
100	0x144976B4L, 0xE622F5B7L, 0xF5720643L, 0x07198540L,
101	0x590AB964L, 0xAB613A67L, 0xB831C993L, 0x4A5A4A90L,
102	0x9E902E7BL, 0x6CFBAD78L, 0x7FAB5E8CL, 0x8DC0DD8FL,
103	0xE330A81AL, 0x115B2B19L, 0x020BD8EDL, 0xF0605BEEL,
104	0x24AA3F05L, 0xD6C1BC06L, 0xC5914FF2L, 0x37FACCF1L,
105	0x69E9F0D5L, 0x9B8273D6L, 0x88D28022L, 0x7AB90321L,
106	0xAE7367CAL, 0x5C18E4C9L, 0x4F48173DL, 0xBD23943EL,
107	0xF36E6F75L, 0x0105EC76L, 0x12551F82L, 0xE03E9C81L,
108	0x34F4F86AL, 0xC69F7B69L, 0xD5CF889DL, 0x27A40B9EL,
109	0x79B737BAL, 0x8BDCB4B9L, 0x988C474DL, 0x6AE7C44EL,
110	0xBE2DA0A5L, 0x4C4623A6L, 0x5F16D052L, 0xAD7D5351L
111};
112
113/*
114 * Steps through buffer one byte at at time, calculates reflected
115 * crc using table.
116 */
117
118uint32_t crc32c_sw(unsigned char const *data, unsigned long length)
119{
120	uint32_t crc = ~0;
121
122	while (length--)
123		crc = crc32c_table[(crc ^ *data++) & 0xFFL] ^ (crc >> 8);
124
125	return crc;
126}
127