1 /* libFLAC - Free Lossless Audio Codec library
2 * Copyright (C) 2000-2009 Josh Coalson
3 * Copyright (C) 2011-2016 Xiph.Org Foundation
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * - Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 *
12 * - Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * - Neither the name of the Xiph.org Foundation nor the names of its
17 * contributors may be used to endorse or promote products derived from
18 * this software without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
23 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR
24 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
25 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
26 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
27 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
28 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
29 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
30 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 */
32
33 #ifdef HAVE_CONFIG_H
34 # include <config.h>
35 #endif
36
37 #include "private/crc.h"
38
39 /* CRC-8, poly = x^8 + x^2 + x^1 + x^0, init = 0 */
40
41 FLAC__byte const FLAC__crc8_table[256] = {
42 0x00, 0x07, 0x0E, 0x09, 0x1C, 0x1B, 0x12, 0x15,
43 0x38, 0x3F, 0x36, 0x31, 0x24, 0x23, 0x2A, 0x2D,
44 0x70, 0x77, 0x7E, 0x79, 0x6C, 0x6B, 0x62, 0x65,
45 0x48, 0x4F, 0x46, 0x41, 0x54, 0x53, 0x5A, 0x5D,
46 0xE0, 0xE7, 0xEE, 0xE9, 0xFC, 0xFB, 0xF2, 0xF5,
47 0xD8, 0xDF, 0xD6, 0xD1, 0xC4, 0xC3, 0xCA, 0xCD,
48 0x90, 0x97, 0x9E, 0x99, 0x8C, 0x8B, 0x82, 0x85,
49 0xA8, 0xAF, 0xA6, 0xA1, 0xB4, 0xB3, 0xBA, 0xBD,
50 0xC7, 0xC0, 0xC9, 0xCE, 0xDB, 0xDC, 0xD5, 0xD2,
51 0xFF, 0xF8, 0xF1, 0xF6, 0xE3, 0xE4, 0xED, 0xEA,
52 0xB7, 0xB0, 0xB9, 0xBE, 0xAB, 0xAC, 0xA5, 0xA2,
53 0x8F, 0x88, 0x81, 0x86, 0x93, 0x94, 0x9D, 0x9A,
54 0x27, 0x20, 0x29, 0x2E, 0x3B, 0x3C, 0x35, 0x32,
55 0x1F, 0x18, 0x11, 0x16, 0x03, 0x04, 0x0D, 0x0A,
56 0x57, 0x50, 0x59, 0x5E, 0x4B, 0x4C, 0x45, 0x42,
57 0x6F, 0x68, 0x61, 0x66, 0x73, 0x74, 0x7D, 0x7A,
58 0x89, 0x8E, 0x87, 0x80, 0x95, 0x92, 0x9B, 0x9C,
59 0xB1, 0xB6, 0xBF, 0xB8, 0xAD, 0xAA, 0xA3, 0xA4,
60 0xF9, 0xFE, 0xF7, 0xF0, 0xE5, 0xE2, 0xEB, 0xEC,
61 0xC1, 0xC6, 0xCF, 0xC8, 0xDD, 0xDA, 0xD3, 0xD4,
62 0x69, 0x6E, 0x67, 0x60, 0x75, 0x72, 0x7B, 0x7C,
63 0x51, 0x56, 0x5F, 0x58, 0x4D, 0x4A, 0x43, 0x44,
64 0x19, 0x1E, 0x17, 0x10, 0x05, 0x02, 0x0B, 0x0C,
65 0x21, 0x26, 0x2F, 0x28, 0x3D, 0x3A, 0x33, 0x34,
66 0x4E, 0x49, 0x40, 0x47, 0x52, 0x55, 0x5C, 0x5B,
67 0x76, 0x71, 0x78, 0x7F, 0x6A, 0x6D, 0x64, 0x63,
68 0x3E, 0x39, 0x30, 0x37, 0x22, 0x25, 0x2C, 0x2B,
69 0x06, 0x01, 0x08, 0x0F, 0x1A, 0x1D, 0x14, 0x13,
70 0xAE, 0xA9, 0xA0, 0xA7, 0xB2, 0xB5, 0xBC, 0xBB,
71 0x96, 0x91, 0x98, 0x9F, 0x8A, 0x8D, 0x84, 0x83,
72 0xDE, 0xD9, 0xD0, 0xD7, 0xC2, 0xC5, 0xCC, 0xCB,
73 0xE6, 0xE1, 0xE8, 0xEF, 0xFA, 0xFD, 0xF4, 0xF3
74 };
75
76 /* CRC-16, poly = x^16 + x^15 + x^2 + x^0, init = 0 */
77
78 unsigned const FLAC__crc16_table[256] = {
79 0x0000, 0x8005, 0x800f, 0x000a, 0x801b, 0x001e, 0x0014, 0x8011,
80 0x8033, 0x0036, 0x003c, 0x8039, 0x0028, 0x802d, 0x8027, 0x0022,
81 0x8063, 0x0066, 0x006c, 0x8069, 0x0078, 0x807d, 0x8077, 0x0072,
82 0x0050, 0x8055, 0x805f, 0x005a, 0x804b, 0x004e, 0x0044, 0x8041,
83 0x80c3, 0x00c6, 0x00cc, 0x80c9, 0x00d8, 0x80dd, 0x80d7, 0x00d2,
84 0x00f0, 0x80f5, 0x80ff, 0x00fa, 0x80eb, 0x00ee, 0x00e4, 0x80e1,
85 0x00a0, 0x80a5, 0x80af, 0x00aa, 0x80bb, 0x00be, 0x00b4, 0x80b1,
86 0x8093, 0x0096, 0x009c, 0x8099, 0x0088, 0x808d, 0x8087, 0x0082,
87 0x8183, 0x0186, 0x018c, 0x8189, 0x0198, 0x819d, 0x8197, 0x0192,
88 0x01b0, 0x81b5, 0x81bf, 0x01ba, 0x81ab, 0x01ae, 0x01a4, 0x81a1,
89 0x01e0, 0x81e5, 0x81ef, 0x01ea, 0x81fb, 0x01fe, 0x01f4, 0x81f1,
90 0x81d3, 0x01d6, 0x01dc, 0x81d9, 0x01c8, 0x81cd, 0x81c7, 0x01c2,
91 0x0140, 0x8145, 0x814f, 0x014a, 0x815b, 0x015e, 0x0154, 0x8151,
92 0x8173, 0x0176, 0x017c, 0x8179, 0x0168, 0x816d, 0x8167, 0x0162,
93 0x8123, 0x0126, 0x012c, 0x8129, 0x0138, 0x813d, 0x8137, 0x0132,
94 0x0110, 0x8115, 0x811f, 0x011a, 0x810b, 0x010e, 0x0104, 0x8101,
95 0x8303, 0x0306, 0x030c, 0x8309, 0x0318, 0x831d, 0x8317, 0x0312,
96 0x0330, 0x8335, 0x833f, 0x033a, 0x832b, 0x032e, 0x0324, 0x8321,
97 0x0360, 0x8365, 0x836f, 0x036a, 0x837b, 0x037e, 0x0374, 0x8371,
98 0x8353, 0x0356, 0x035c, 0x8359, 0x0348, 0x834d, 0x8347, 0x0342,
99 0x03c0, 0x83c5, 0x83cf, 0x03ca, 0x83db, 0x03de, 0x03d4, 0x83d1,
100 0x83f3, 0x03f6, 0x03fc, 0x83f9, 0x03e8, 0x83ed, 0x83e7, 0x03e2,
101 0x83a3, 0x03a6, 0x03ac, 0x83a9, 0x03b8, 0x83bd, 0x83b7, 0x03b2,
102 0x0390, 0x8395, 0x839f, 0x039a, 0x838b, 0x038e, 0x0384, 0x8381,
103 0x0280, 0x8285, 0x828f, 0x028a, 0x829b, 0x029e, 0x0294, 0x8291,
104 0x82b3, 0x02b6, 0x02bc, 0x82b9, 0x02a8, 0x82ad, 0x82a7, 0x02a2,
105 0x82e3, 0x02e6, 0x02ec, 0x82e9, 0x02f8, 0x82fd, 0x82f7, 0x02f2,
106 0x02d0, 0x82d5, 0x82df, 0x02da, 0x82cb, 0x02ce, 0x02c4, 0x82c1,
107 0x8243, 0x0246, 0x024c, 0x8249, 0x0258, 0x825d, 0x8257, 0x0252,
108 0x0270, 0x8275, 0x827f, 0x027a, 0x826b, 0x026e, 0x0264, 0x8261,
109 0x0220, 0x8225, 0x822f, 0x022a, 0x823b, 0x023e, 0x0234, 0x8231,
110 0x8213, 0x0216, 0x021c, 0x8219, 0x0208, 0x820d, 0x8207, 0x0202
111 };
112
113
FLAC__crc8_update(const FLAC__byte data,FLAC__uint8 * crc)114 void FLAC__crc8_update(const FLAC__byte data, FLAC__uint8 *crc)
115 {
116 *crc = FLAC__crc8_table[*crc ^ data];
117 }
118
FLAC__crc8_update_block(const FLAC__byte * data,unsigned len,FLAC__uint8 * crc)119 void FLAC__crc8_update_block(const FLAC__byte *data, unsigned len, FLAC__uint8 *crc)
120 {
121 while(len--)
122 *crc = FLAC__crc8_table[*crc ^ *data++];
123 }
124
FLAC__crc8(const FLAC__byte * data,unsigned len)125 FLAC__uint8 FLAC__crc8(const FLAC__byte *data, unsigned len)
126 {
127 FLAC__uint8 crc = 0;
128
129 while(len--)
130 crc = FLAC__crc8_table[crc ^ *data++];
131
132 return crc;
133 }
134
FLAC__crc16(const FLAC__byte * data,unsigned len)135 unsigned FLAC__crc16(const FLAC__byte *data, unsigned len)
136 {
137 unsigned crc = 0;
138
139 while(len--)
140 crc = ((crc<<8) ^ FLAC__crc16_table[(crc>>8) ^ *data++]) & 0xffff;
141
142 return crc;
143 }
144