Subversion Repositories HelenOS

Rev

Rev 4722 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
4075 mejdrech 1
/*
2
 * Copyright (c) 2009 Lukas Mejdrech
3
 * All rights reserved.
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
 * - Redistributions in binary form must reproduce the above copyright
12
 *   notice, this list of conditions and the following disclaimer in the
13
 *   documentation and/or other materials provided with the distribution.
14
 * - The name of the author may not be used to endorse or promote products
15
 *   derived from this software without specific prior written permission.
16
 *
17
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
 */
28
 
29
/** @addtogroup net
30
 *  @{
31
 */
32
 
33
/** @file
4505 mejdrech 34
 *  General CRC and checksum computation.
4075 mejdrech 35
 */
36
 
4743 mejdrech 37
#ifndef __NET_CHECKSUM_H__
38
#define __NET_CHECKSUM_H__
4075 mejdrech 39
 
40
#include <byteorder.h>
41
 
42
#include <sys/types.h>
43
 
44
/** Computes CRC32 value.
45
 *  @param seed Initial value. Often used as 0 or ~0. Input parameter.
46
 *  @param data Pointer to the beginning of data to process. Input parameter.
47
 *  @param length Length of the data in bits. Input parameter.
48
 *  @returns The computed CRC32 of the length bits of the data.
49
 */
50
#ifdef ARCH_IS_BIG_ENDIAN
51
    #define compute_crc32( seed, data, length ) compute_crc32_be( seed, ( uint8_t * ) data, length )
52
#else
53
    #define compute_crc32( seed, data, length ) compute_crc32_le( seed, ( uint8_t * ) data, length )
54
#endif
55
 
56
/** Computes CRC32 value in the little-endian environment.
57
 *  @param seed Initial value. Often used as 0 or ~0. Input parameter.
58
 *  @param data Pointer to the beginning of data to process. Input parameter.
59
 *  @param length Length of the data in bits. Input parameter.
60
 *  @returns The computed CRC32 of the length bits of the data.
61
 */
4558 mejdrech 62
uint32_t    compute_crc32_le( uint32_t seed, uint8_t * data, size_t length );
4075 mejdrech 63
 
64
/** Computes CRC32 value in the big-endian environment.
65
 *  @param seed Initial value. Often used as 0 or ~0. Input parameter.
66
 *  @param data Pointer to the beginning of data to process. Input parameter.
67
 *  @param length Length of the data in bits. Input parameter.
68
 *  @returns The computed CRC32 of the length bits of the data.
69
 */
4558 mejdrech 70
uint32_t    compute_crc32_be( uint32_t seed, uint8_t * data, size_t length );
4075 mejdrech 71
 
4505 mejdrech 72
/** Computes sum of the 2 byte fields.
73
 *  Padds one zero (0) byte if odd.
74
 *  @param seed Initial value. Often used as 0 or ~0. Input parameter.
75
 *  @param data Pointer to the beginning of data to process. Input parameter.
76
 *  @param length Length of the data in bytes. Input parameter.
77
 *  @returns The computed checksum of the length bytes of the data.
78
 */
4558 mejdrech 79
uint32_t    compute_checksum( uint32_t seed, uint8_t * data, size_t length );
4505 mejdrech 80
 
81
/** Compacts the computed checksum to the 16 bit number adding the carries.
4699 mejdrech 82
 *  @param sum Computed checksum. Input parameter.
4505 mejdrech 83
 *  @returns Compacted computed checksum to the 16 bits.
84
 */
85
uint16_t    compact_checksum( uint32_t sum );
86
 
4722 mejdrech 87
/** Returns or flips the checksum if zero.
88
 *  @param checksum The computed checksum. Input parameter.
89
 *  @returns The internet protocol header checksum.
90
 *  @returns 0xFFFF if the computed checksum is zero.
91
 */
92
uint16_t    flip_checksum( uint16_t checksum );
93
 
4711 mejdrech 94
/** Computes the ip header checksum.
95
 *  To compute the checksum of a new packet, the checksum header field must be zero.
96
 *  To check the checksum of a received packet, the checksum may be left set.
4722 mejdrech 97
 *  The zero (0) value will be returned in this case if valid.
4711 mejdrech 98
 *  @param data The header data. Input parameter.
99
 *  @param length The header length in bytes. Input parameter.
100
 *  @returns The internet protocol header checksum.
101
 *  @returns 0xFFFF if the computed checksum is zero.
102
 */
103
uint16_t ip_checksum( uint8_t * data, size_t length );
104
 
4075 mejdrech 105
#endif
106
 
107
/** @}
108
 */