Minor code reordering and documentation adjustments.
[dragonfly.git] / sys / netinet / sctp_crc32.c
blob02a526c84e37a2b29cd6adbbbb3ad1bbe277f8eb
1 /* $KAME: sctp_crc32.c,v 1.11 2004/08/17 04:06:16 itojun Exp $ */
2 /* $DragonFly: src/sys/netinet/sctp_crc32.c,v 1.1 2005/07/15 14:46:16 eirikn Exp $ */
4 /*
5 * Copyright (c) 2001, 2002, 2003, 2004 Cisco Systems, Inc.
6 * All rights reserved.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. 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 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by Cisco Systems, Inc.
19 * 4. Neither the name of the project nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
23 * THIS SOFTWARE IS PROVIDED BY CISCO SYSTEMS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL CISCO SYSTEMS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
35 #ifdef __APPLE__
36 #include <sctp.h>
37 #elif !defined(__OpenBSD__)
38 #include "opt_sctp.h"
39 #endif
40 #include <sys/param.h>
41 #include <netinet/sctp_crc32.h>
43 #ifndef SCTP_USE_ADLER32
45 #define SCTP_CRC32C_POLY 0x1EDC6F41
46 #define SCTP_CRC32C(c, d) (c = ((c) >> 8) ^ sctp_crc_c[((c) ^ (d)) & 0xFF])
48 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
49 /* Copyright 2001, D. Otis. Use this program, code or tables */
50 /* extracted from it, as desired without restriction. */
51 /* */
52 /* 32 Bit Reflected CRC table generation for SCTP. */
53 /* To accommodate serial byte data being shifted out least */
54 /* significant bit first, the table's 32 bit words are reflected */
55 /* which flips both byte and bit MS and LS positions. The CRC */
56 /* is calculated MS bits first from the perspective of the serial*/
57 /* stream. The x^32 term is implied and the x^0 term may also */
58 /* be shown as +1. The polynomial code used is 0x1EDC6F41. */
59 /* Castagnoli93 */
60 /* x^32+x^28+x^27+x^26+x^25+x^23+x^22+x^20+x^19+x^18+x^14+x^13+ */
61 /* x^11+x^10+x^9+x^8+x^6+x^0 */
62 /* Guy Castagnoli Stefan Braeuer and Martin Herrman */
63 /* "Optimization of Cyclic Redundancy-Check Codes */
64 /* with 24 and 32 Parity Bits", */
65 /* IEEE Transactions on Communications, Vol.41, No.6, June 1993 */
66 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
68 unsigned long sctp_crc_c[256] = {
69 0x00000000L, 0xF26B8303L, 0xE13B70F7L, 0x1350F3F4L,
70 0xC79A971FL, 0x35F1141CL, 0x26A1E7E8L, 0xD4CA64EBL,
71 0x8AD958CFL, 0x78B2DBCCL, 0x6BE22838L, 0x9989AB3BL,
72 0x4D43CFD0L, 0xBF284CD3L, 0xAC78BF27L, 0x5E133C24L,
73 0x105EC76FL, 0xE235446CL, 0xF165B798L, 0x030E349BL,
74 0xD7C45070L, 0x25AFD373L, 0x36FF2087L, 0xC494A384L,
75 0x9A879FA0L, 0x68EC1CA3L, 0x7BBCEF57L, 0x89D76C54L,
76 0x5D1D08BFL, 0xAF768BBCL, 0xBC267848L, 0x4E4DFB4BL,
77 0x20BD8EDEL, 0xD2D60DDDL, 0xC186FE29L, 0x33ED7D2AL,
78 0xE72719C1L, 0x154C9AC2L, 0x061C6936L, 0xF477EA35L,
79 0xAA64D611L, 0x580F5512L, 0x4B5FA6E6L, 0xB93425E5L,
80 0x6DFE410EL, 0x9F95C20DL, 0x8CC531F9L, 0x7EAEB2FAL,
81 0x30E349B1L, 0xC288CAB2L, 0xD1D83946L, 0x23B3BA45L,
82 0xF779DEAEL, 0x05125DADL, 0x1642AE59L, 0xE4292D5AL,
83 0xBA3A117EL, 0x4851927DL, 0x5B016189L, 0xA96AE28AL,
84 0x7DA08661L, 0x8FCB0562L, 0x9C9BF696L, 0x6EF07595L,
85 0x417B1DBCL, 0xB3109EBFL, 0xA0406D4BL, 0x522BEE48L,
86 0x86E18AA3L, 0x748A09A0L, 0x67DAFA54L, 0x95B17957L,
87 0xCBA24573L, 0x39C9C670L, 0x2A993584L, 0xD8F2B687L,
88 0x0C38D26CL, 0xFE53516FL, 0xED03A29BL, 0x1F682198L,
89 0x5125DAD3L, 0xA34E59D0L, 0xB01EAA24L, 0x42752927L,
90 0x96BF4DCCL, 0x64D4CECFL, 0x77843D3BL, 0x85EFBE38L,
91 0xDBFC821CL, 0x2997011FL, 0x3AC7F2EBL, 0xC8AC71E8L,
92 0x1C661503L, 0xEE0D9600L, 0xFD5D65F4L, 0x0F36E6F7L,
93 0x61C69362L, 0x93AD1061L, 0x80FDE395L, 0x72966096L,
94 0xA65C047DL, 0x5437877EL, 0x4767748AL, 0xB50CF789L,
95 0xEB1FCBADL, 0x197448AEL, 0x0A24BB5AL, 0xF84F3859L,
96 0x2C855CB2L, 0xDEEEDFB1L, 0xCDBE2C45L, 0x3FD5AF46L,
97 0x7198540DL, 0x83F3D70EL, 0x90A324FAL, 0x62C8A7F9L,
98 0xB602C312L, 0x44694011L, 0x5739B3E5L, 0xA55230E6L,
99 0xFB410CC2L, 0x092A8FC1L, 0x1A7A7C35L, 0xE811FF36L,
100 0x3CDB9BDDL, 0xCEB018DEL, 0xDDE0EB2AL, 0x2F8B6829L,
101 0x82F63B78L, 0x709DB87BL, 0x63CD4B8FL, 0x91A6C88CL,
102 0x456CAC67L, 0xB7072F64L, 0xA457DC90L, 0x563C5F93L,
103 0x082F63B7L, 0xFA44E0B4L, 0xE9141340L, 0x1B7F9043L,
104 0xCFB5F4A8L, 0x3DDE77ABL, 0x2E8E845FL, 0xDCE5075CL,
105 0x92A8FC17L, 0x60C37F14L, 0x73938CE0L, 0x81F80FE3L,
106 0x55326B08L, 0xA759E80BL, 0xB4091BFFL, 0x466298FCL,
107 0x1871A4D8L, 0xEA1A27DBL, 0xF94AD42FL, 0x0B21572CL,
108 0xDFEB33C7L, 0x2D80B0C4L, 0x3ED04330L, 0xCCBBC033L,
109 0xA24BB5A6L, 0x502036A5L, 0x4370C551L, 0xB11B4652L,
110 0x65D122B9L, 0x97BAA1BAL, 0x84EA524EL, 0x7681D14DL,
111 0x2892ED69L, 0xDAF96E6AL, 0xC9A99D9EL, 0x3BC21E9DL,
112 0xEF087A76L, 0x1D63F975L, 0x0E330A81L, 0xFC588982L,
113 0xB21572C9L, 0x407EF1CAL, 0x532E023EL, 0xA145813DL,
114 0x758FE5D6L, 0x87E466D5L, 0x94B49521L, 0x66DF1622L,
115 0x38CC2A06L, 0xCAA7A905L, 0xD9F75AF1L, 0x2B9CD9F2L,
116 0xFF56BD19L, 0x0D3D3E1AL, 0x1E6DCDEEL, 0xEC064EEDL,
117 0xC38D26C4L, 0x31E6A5C7L, 0x22B65633L, 0xD0DDD530L,
118 0x0417B1DBL, 0xF67C32D8L, 0xE52CC12CL, 0x1747422FL,
119 0x49547E0BL, 0xBB3FFD08L, 0xA86F0EFCL, 0x5A048DFFL,
120 0x8ECEE914L, 0x7CA56A17L, 0x6FF599E3L, 0x9D9E1AE0L,
121 0xD3D3E1ABL, 0x21B862A8L, 0x32E8915CL, 0xC083125FL,
122 0x144976B4L, 0xE622F5B7L, 0xF5720643L, 0x07198540L,
123 0x590AB964L, 0xAB613A67L, 0xB831C993L, 0x4A5A4A90L,
124 0x9E902E7BL, 0x6CFBAD78L, 0x7FAB5E8CL, 0x8DC0DD8FL,
125 0xE330A81AL, 0x115B2B19L, 0x020BD8EDL, 0xF0605BEEL,
126 0x24AA3F05L, 0xD6C1BC06L, 0xC5914FF2L, 0x37FACCF1L,
127 0x69E9F0D5L, 0x9B8273D6L, 0x88D28022L, 0x7AB90321L,
128 0xAE7367CAL, 0x5C18E4C9L, 0x4F48173DL, 0xBD23943EL,
129 0xF36E6F75L, 0x0105EC76L, 0x12551F82L, 0xE03E9C81L,
130 0x34F4F86AL, 0xC69F7B69L, 0xD5CF889DL, 0x27A40B9EL,
131 0x79B737BAL, 0x8BDCB4B9L, 0x988C474DL, 0x6AE7C44EL,
132 0xBE2DA0A5L, 0x4C4623A6L, 0x5F16D052L, 0xAD7D5351L,
135 u_int32_t
136 update_crc32(u_int32_t crc32,
137 unsigned char *buffer,
138 unsigned int length)
140 unsigned int i;
142 for (i = 0; i < length; i++) {
143 SCTP_CRC32C(crc32, buffer[i]);
145 return (crc32);
149 u_int32_t
150 sctp_csum_finalize(u_int32_t crc32)
152 u_int32_t result;
153 #if BYTE_ORDER == BIG_ENDIAN
154 u_int8_t byte0, byte1, byte2, byte3;
155 #endif
156 /* Complement the result */
157 result = ~crc32;
158 #if BYTE_ORDER == BIG_ENDIAN
160 * For BIG-ENDIAN.. aka Motorola byte order the result is in
161 * little-endian form. So we must manually swap the bytes. Then
162 * we can call htonl() which does nothing...
164 byte0 = result & 0x000000ff;
165 byte1 = (result >> 8) & 0x000000ff;
166 byte2 = (result >> 16) & 0x000000ff;
167 byte3 = (result >> 24) & 0x000000ff;
168 result = ((byte0 << 24) | (byte1 << 16) | (byte2 << 8) | byte3);
169 crc32 = htonl(result);
170 #else
172 * For INTEL platforms the result comes out in network order.
173 * No htonl is required or the swap above. So we optimize out
174 * both the htonl and the manual swap above.
176 crc32 = result;
177 #endif
178 return (crc32);
181 #endif