u-boot/include/hash.h
Simon Glass 6f907b422e hash: Add a way to calculate a hash for any algortihm
Rather than needing to call one of many hashing algorithms in U-Boot,
provide a function hash_block() which handles this, and can support all
available hash algorithms.

Once we have md5 supported within hashing, we can use this function in
the FIT image code.

Signed-off-by: Simon Glass <sjg@chromium.org>
2013-05-14 15:37:24 -04:00

96 lines
3.3 KiB
C

/*
* Copyright (c) 2012 The Chromium OS Authors.
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#ifndef _HASH_H
#define _HASH_H
#if defined(CONFIG_SHA1SUM_VERIFY) || defined(CONFIG_CRC32_VERIFY)
#define CONFIG_HASH_VERIFY
#endif
struct hash_algo {
const char *name; /* Name of algorithm */
int digest_size; /* Length of digest */
/**
* hash_func_ws: Generic hashing function
*
* This is the generic prototype for a hashing function. We only
* have the watchdog version at present.
*
* @input: Input buffer
* @ilen: Input buffer length
* @output: Checksum result (length depends on algorithm)
* @chunk_sz: Trigger watchdog after processing this many bytes
*/
void (*hash_func_ws)(const unsigned char *input, unsigned int ilen,
unsigned char *output, unsigned int chunk_sz);
int chunk_size; /* Watchdog chunk size */
};
/*
* Maximum digest size for all algorithms we support. Having this value
* avoids a malloc() or C99 local declaration in common/cmd_hash.c.
*/
#define HASH_MAX_DIGEST_SIZE 32
enum {
HASH_FLAG_VERIFY = 1 << 0, /* Enable verify mode */
HASH_FLAG_ENV = 1 << 1, /* Allow env vars */
};
/**
* hash_command: Process a hash command for a particular algorithm
*
* This common function is used to implement specific hash commands.
*
* @algo_name: Hash algorithm being used (lower case!)
* @flags: Flags value (HASH_FLAG_...)
* @cmdtp: Pointer to command table entry
* @flag: Some flags normally 0 (see CMD_FLAG_.. above)
* @argc: Number of arguments (arg 0 must be the command text)
* @argv: Arguments
*/
int hash_command(const char *algo_name, int flags, cmd_tbl_t *cmdtp, int flag,
int argc, char * const argv[]);
/**
* hash_block() - Hash a block according to the requested algorithm
*
* The caller probably knows the hash length for the chosen algorithm, but
* in order to provide a general interface, and output_size parameter is
* provided.
*
* @algo_name: Hash algorithm to use
* @data: Data to hash
* @len: Lengh of data to hash in bytes
* @output: Place to put hash value
* @output_size: On entry, pointer to the number of bytes available in
* output. On exit, pointer to the number of bytes used.
* If NULL, then it is assumed that the caller has
* allocated enough space for the hash. This is possible
* since the caller is selecting the algorithm.
* @return 0 if ok, -ve on error: -EPROTONOSUPPORT for an unknown algorithm,
* -ENOSPC if the output buffer is not large enough.
*/
int hash_block(const char *algo_name, const void *data, unsigned int len,
uint8_t *output, int *output_size);
#endif