gecko/security/nss/lib/freebl/alghmac.c
2009-01-21 04:43:31 +01:00

198 lines
5.7 KiB
C

/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is the Netscape security libraries.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1994-2000
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#ifdef FREEBL_NO_DEPEND
#include "stubs.h"
#endif
#include "secport.h"
#include "hasht.h"
#include "blapit.h"
#include "alghmac.h"
#include "secerr.h"
#define HMAC_PAD_SIZE HASH_BLOCK_LENGTH_MAX
struct HMACContextStr {
void *hash;
const SECHashObject *hashobj;
PRBool wasAllocated;
unsigned char ipad[HMAC_PAD_SIZE];
unsigned char opad[HMAC_PAD_SIZE];
};
void
HMAC_Destroy(HMACContext *cx, PRBool freeit)
{
if (cx == NULL)
return;
PORT_Assert(!freeit == !cx->wasAllocated);
if (cx->hash != NULL) {
cx->hashobj->destroy(cx->hash, PR_TRUE);
PORT_Memset(cx, 0, sizeof *cx);
}
if (freeit)
PORT_Free(cx);
}
SECStatus
HMAC_Init( HMACContext * cx, const SECHashObject *hash_obj,
const unsigned char *secret, unsigned int secret_len, PRBool isFIPS)
{
unsigned int i;
unsigned char hashed_secret[HASH_LENGTH_MAX];
/* required by FIPS 198 Section 3 */
if (isFIPS && secret_len < hash_obj->length/2) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
return SECFailure;
}
if (cx == NULL) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
return SECFailure;
}
cx->wasAllocated = PR_FALSE;
cx->hashobj = hash_obj;
cx->hash = cx->hashobj->create();
if (cx->hash == NULL)
goto loser;
if (secret_len > cx->hashobj->blocklength) {
cx->hashobj->begin( cx->hash);
cx->hashobj->update(cx->hash, secret, secret_len);
PORT_Assert(cx->hashobj->length <= sizeof hashed_secret);
cx->hashobj->end( cx->hash, hashed_secret, &secret_len,
sizeof hashed_secret);
if (secret_len != cx->hashobj->length) {
PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
goto loser;
}
secret = (const unsigned char *)&hashed_secret[0];
}
PORT_Memset(cx->ipad, 0x36, cx->hashobj->blocklength);
PORT_Memset(cx->opad, 0x5c, cx->hashobj->blocklength);
/* fold secret into padding */
for (i = 0; i < secret_len; i++) {
cx->ipad[i] ^= secret[i];
cx->opad[i] ^= secret[i];
}
PORT_Memset(hashed_secret, 0, sizeof hashed_secret);
return SECSuccess;
loser:
PORT_Memset(hashed_secret, 0, sizeof hashed_secret);
if (cx->hash != NULL)
cx->hashobj->destroy(cx->hash, PR_TRUE);
return SECFailure;
}
HMACContext *
HMAC_Create(const SECHashObject *hash_obj, const unsigned char *secret,
unsigned int secret_len, PRBool isFIPS)
{
SECStatus rv;
HMACContext * cx = PORT_ZNew(HMACContext);
if (cx == NULL)
return NULL;
rv = HMAC_Init(cx, hash_obj, secret, secret_len, isFIPS);
cx->wasAllocated = PR_TRUE;
if (rv != SECSuccess) {
PORT_Free(cx); /* contains no secret info */
cx = NULL;
}
return cx;
}
void
HMAC_Begin(HMACContext *cx)
{
/* start inner hash */
cx->hashobj->begin(cx->hash);
cx->hashobj->update(cx->hash, cx->ipad, cx->hashobj->blocklength);
}
void
HMAC_Update(HMACContext *cx, const unsigned char *data, unsigned int data_len)
{
cx->hashobj->update(cx->hash, data, data_len);
}
SECStatus
HMAC_Finish(HMACContext *cx, unsigned char *result, unsigned int *result_len,
unsigned int max_result_len)
{
if (max_result_len < cx->hashobj->length) {
PORT_SetError(SEC_ERROR_INVALID_ARGS);
return SECFailure;
}
cx->hashobj->end(cx->hash, result, result_len, max_result_len);
if (*result_len != cx->hashobj->length)
return SECFailure;
cx->hashobj->begin(cx->hash);
cx->hashobj->update(cx->hash, cx->opad, cx->hashobj->blocklength);
cx->hashobj->update(cx->hash, result, *result_len);
cx->hashobj->end(cx->hash, result, result_len, max_result_len);
return SECSuccess;
}
HMACContext *
HMAC_Clone(HMACContext *cx)
{
HMACContext *newcx;
newcx = (HMACContext*)PORT_ZAlloc(sizeof(HMACContext));
if (newcx == NULL)
goto loser;
newcx->wasAllocated = PR_TRUE;
newcx->hashobj = cx->hashobj;
newcx->hash = cx->hashobj->clone(cx->hash);
if (newcx->hash == NULL)
goto loser;
PORT_Memcpy(newcx->ipad, cx->ipad, cx->hashobj->blocklength);
PORT_Memcpy(newcx->opad, cx->opad, cx->hashobj->blocklength);
return newcx;
loser:
HMAC_Destroy(newcx, PR_TRUE);
return NULL;
}