crc32.c File Reference

#include <ipxe/crc32.h>

Go to the source code of this file.

Macros
#define	CRCPOLY   0xedb88320

Functions
	FILE_LICENCE (GPL2_OR_LATER)
u32	crc32_le (u32 seed, const void *data, size_t len)
	Calculate 32-bit little-endian CRC checksum. More...

Macro Definition Documentation

CRCPOLY

#define CRCPOLY   0xedb88320

Definition at line 26 of file crc32.c.

Function Documentation

FILE_LICENCE()

FILE_LICENCE

(

GPL2_OR_LATER

)

crc32_le()

u32 crc32_le	(	u32	seed,
		const void *	data,
		size_t	len
	)

Calculate 32-bit little-endian CRC checksum.

Parameters

seed	Initial value
data	Data to checksum
len	Length of data

Usually seed is initially zero or all one bits, depending on the protocol. To continue a CRC checksum over multiple calls, pass the return value from one call as the seed parameter to the next.

Definition at line 39 of file crc32.c.

{
        u32 crc = seed;
        const u8 *src = data;
        u32 mult;
        int i;

        while ( len-- ) {
                crc ^= *src++;
                for ( i = 0; i < 8; i++ ) {
                        mult = ( crc & 1 ) ? CRCPOLY : 0;
                        crc = ( crc >> 1 ) ^ mult;
                }
        }

        return crc;
}

References CRCPOLY, data, len, and src.

Referenced by efirng_get_noise(), fcoe_deliver(), fcoe_rx(), icmpcol(), ipv6col(), start_dhcpv6(), tkip_decrypt(), tkip_encrypt(), validator_start_download(), wep_decrypt(), and wep_encrypt().