mirror of
https://github.com/HamletDuFromage/sigpatches-updater.git
synced 2024-11-29 23:32:29 +00:00
145 lines
5.1 KiB
C
145 lines
5.1 KiB
C
/*
|
|
---------------------------------------------------------------------------
|
|
Copyright (c) 2002, Dr Brian Gladman, Worcester, UK. All rights reserved.
|
|
|
|
LICENSE TERMS
|
|
|
|
The free distribution and use of this software in both source and binary
|
|
form is allowed (with or without changes) provided that:
|
|
|
|
1. distributions of this source code include the above copyright
|
|
notice, this list of conditions and the following disclaimer;
|
|
|
|
2. distributions in binary form include the above copyright
|
|
notice, this list of conditions and the following disclaimer
|
|
in the documentation and/or other associated materials;
|
|
|
|
3. the copyright holder's name is not used to endorse products
|
|
built using this software without specific written permission.
|
|
|
|
ALTERNATIVELY, provided that this notice is retained in full, this product
|
|
may be distributed under the terms of the GNU General Public License (GPL),
|
|
in which case the provisions of the GPL apply INSTEAD OF those given above.
|
|
|
|
DISCLAIMER
|
|
|
|
This software is provided 'as is' with no explicit or implied warranties
|
|
in respect of its properties, including, but not limited to, correctness
|
|
and/or fitness for purpose.
|
|
---------------------------------------------------------------------------
|
|
Issue Date: 26/08/2003
|
|
|
|
This is an implementation of HMAC, the FIPS standard keyed hash function
|
|
*/
|
|
|
|
#include "hmac.h"
|
|
#include "brg_types.h"
|
|
|
|
#if defined(__cplusplus)
|
|
extern "C"
|
|
{
|
|
#endif
|
|
|
|
/* initialise the HMAC context to zero */
|
|
void hmac_sha_begin(hmac_ctx cx[1])
|
|
{
|
|
memset(cx, 0, sizeof(hmac_ctx));
|
|
}
|
|
|
|
/* input the HMAC key (can be called multiple times) */
|
|
int hmac_sha_key(const unsigned char key[], unsigned long key_len, hmac_ctx cx[1])
|
|
{
|
|
if(cx->klen == HMAC_IN_DATA) /* error if further key input */
|
|
return HMAC_BAD_MODE; /* is attempted in data mode */
|
|
|
|
if(cx->klen + key_len > HASH_INPUT_SIZE) /* if the key has to be hashed */
|
|
{
|
|
if(cx->klen <= HASH_INPUT_SIZE) /* if the hash has not yet been */
|
|
{ /* started, initialise it and */
|
|
sha_begin(cx->ctx); /* hash stored key characters */
|
|
sha_hash(cx->key, cx->klen, cx->ctx);
|
|
}
|
|
|
|
sha_hash(key, key_len, cx->ctx); /* hash long key data into hash */
|
|
}
|
|
else /* otherwise store key data */
|
|
memcpy(cx->key + cx->klen, key, key_len);
|
|
|
|
cx->klen += key_len; /* update the key length count */
|
|
return HMAC_OK;
|
|
}
|
|
|
|
/* input the HMAC data (can be called multiple times) - */
|
|
/* note that this call terminates the key input phase */
|
|
void hmac_sha_data(const unsigned char data[], unsigned long data_len, hmac_ctx cx[1])
|
|
{ unsigned int i;
|
|
|
|
if(cx->klen != HMAC_IN_DATA) /* if not yet in data phase */
|
|
{
|
|
if(cx->klen > HASH_INPUT_SIZE) /* if key is being hashed */
|
|
{ /* complete the hash and */
|
|
sha_end(cx->key, cx->ctx); /* store the result as the */
|
|
cx->klen = HASH_OUTPUT_SIZE; /* key and set new length */
|
|
}
|
|
|
|
/* pad the key if necessary */
|
|
memset(cx->key + cx->klen, 0, HASH_INPUT_SIZE - cx->klen);
|
|
|
|
/* xor ipad into key value */
|
|
for(i = 0; i < (HASH_INPUT_SIZE >> 2); ++i)
|
|
((uint_32t*)cx->key)[i] ^= 0x36363636;
|
|
|
|
/* and start hash operation */
|
|
sha_begin(cx->ctx);
|
|
sha_hash(cx->key, HASH_INPUT_SIZE, cx->ctx);
|
|
|
|
/* mark as now in data mode */
|
|
cx->klen = HMAC_IN_DATA;
|
|
}
|
|
|
|
/* hash the data (if any) */
|
|
if(data_len)
|
|
sha_hash(data, data_len, cx->ctx);
|
|
}
|
|
|
|
/* compute and output the MAC value */
|
|
void hmac_sha_end(unsigned char mac[], unsigned long mac_len, hmac_ctx cx[1])
|
|
{ unsigned char dig[HASH_OUTPUT_SIZE];
|
|
unsigned int i;
|
|
|
|
/* if no data has been entered perform a null data phase */
|
|
if(cx->klen != HMAC_IN_DATA)
|
|
hmac_sha_data((const unsigned char*)0, 0, cx);
|
|
|
|
sha_end(dig, cx->ctx); /* complete the inner hash */
|
|
|
|
/* set outer key value using opad and removing ipad */
|
|
for(i = 0; i < (HASH_INPUT_SIZE >> 2); ++i)
|
|
((uint_32t*)cx->key)[i] ^= 0x36363636 ^ 0x5c5c5c5c;
|
|
|
|
/* perform the outer hash operation */
|
|
sha_begin(cx->ctx);
|
|
sha_hash(cx->key, HASH_INPUT_SIZE, cx->ctx);
|
|
sha_hash(dig, HASH_OUTPUT_SIZE, cx->ctx);
|
|
sha_end(dig, cx->ctx);
|
|
|
|
/* output the hash value */
|
|
for(i = 0; i < mac_len; ++i)
|
|
mac[i] = dig[i];
|
|
}
|
|
|
|
/* 'do it all in one go' subroutine */
|
|
void hmac_sha(const unsigned char key[], unsigned long key_len,
|
|
const unsigned char data[], unsigned long data_len,
|
|
unsigned char mac[], unsigned long mac_len)
|
|
{ hmac_ctx cx[1];
|
|
|
|
hmac_sha_begin(cx);
|
|
hmac_sha_key(key, key_len, cx);
|
|
hmac_sha_data(data, data_len, cx);
|
|
hmac_sha_end(mac, mac_len, cx);
|
|
}
|
|
|
|
#if defined(__cplusplus)
|
|
}
|
|
#endif
|