freebsd-nq/sys/opencrypto/cbc_mac.h
John Baldwin 4361c4eb6e cryptosoft: Fix support for variable tag lengths in AES-CCM.
The tag length is included as one of the values in the flags byte of
block 0 passed to CBC_MAC, so merely copying the first N bytes is
insufficient.

To avoid adding more sideband data to the CBC MAC software context,
pull the generation of block 0, the AAD length, and AAD padding out of
cbc_mac.c and into cryptosoft.c.  This matches how GCM/GMAC are
handled where the length block is constructed in cryptosoft.c and
passed as an input to the Update callback.  As a result, the CBC MAC
Update() routine is now much simpler and simply performs the
XOR-and-encrypt step on each input block.

While here, avoid a copy to the staging block in the Update routine
when one or more full blocks are passed as input to the Update
callback.

Reviewed by:	sef
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D32120
2021-10-06 14:08:48 -07:00

66 lines
2.3 KiB
C

/*
* Copyright (c) 2014 The FreeBSD Foundation
* Copyright (c) 2018, iXsystems Inc.
* All rights reserved.
*
* This software was developed by Sean Eric Fagan, with lots of references
* to existing AES-CCM (gmac) code.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*
*/
#ifndef _CBC_CCM_H
# define _CBC_CCM_H
# include <sys/types.h>
# include <crypto/rijndael/rijndael.h>
# define CCM_CBC_BLOCK_LEN 16 /* 128 bits */
# define CCM_CBC_MAX_DIGEST_LEN 16
# define CCM_CBC_MIN_DIGEST_LEN 4
/*
* This is the authentication context structure;
* the encryption one is similar.
*/
struct aes_cbc_mac_ctx {
uint8_t staging_block[CCM_CBC_BLOCK_LEN];
uint8_t block[CCM_CBC_BLOCK_LEN];
int blockIndex;
int nonceLength; /* This one is in bytes, not bits! */
const uint8_t *nonce;
/* AES state data */
int rounds;
uint32_t keysched[4*(RIJNDAEL_MAXNR+1)];
};
void AES_CBC_MAC_Init(void *);
void AES_CBC_MAC_Setkey(void *, const uint8_t *, u_int);
void AES_CBC_MAC_Reinit(void *, const uint8_t *, u_int);
int AES_CBC_MAC_Update(void *, const void *, u_int);
void AES_CBC_MAC_Final(uint8_t *, void *);
#endif /* _CBC_CCM_H */