freebsd-skq/sys/opencrypto/xform_enc.h
John Baldwin 723d87648e Improve support for stream ciphers in the software encryption interface.
Add a 'native_blocksize' member to 'struct enc_xform' that ciphers can
use if they support a partial final block.  This is particular useful
for stream ciphers, but can also apply to other ciphers.  cryptosoft
will only pass in native blocks to the encrypt and decrypt hooks.  For
the final partial block, 'struct enc_xform' now has new
encrypt_last/decrypt_last hooks which accept the length of the final
block.  The multi_block methods are also retired.

Mark AES-ICM (AES-CTR) as a stream cipher.  This has some interesting
effects on IPsec in that FreeBSD can now properly receive all packets
sent by Linux when using AES-CTR, but FreeBSD can no longer
interoperate with OpenBSD and older verisons of FreeBSD which assume
AES-CTR packets have a payload padded to a 16-byte boundary.  Kornel
has offered to work on a patch to add a compatiblity sysctl to enforce
additional padding for AES-CTR in esp_output to permit compatibility
with OpenBSD and older versions of FreeBSD.

AES-XTS continues to use a block size of a single AES block length.
It is possible to adjust it to support partial final blocks by
implementing cipher text stealing via encrypt_last/decrypt_last hooks,
but I have not done so.

Reviewed by:	cem (earlier version)
Tested by:	Kornel Dulęba <mindal@semihalf.com> (AES-CTR with IPsec)
Sponsored by:	Netflix
Differential Revision:	https://reviews.freebsd.org/D24906
2020-05-22 16:29:09 +00:00

100 lines
3.0 KiB
C

/* $FreeBSD$ */
/* $OpenBSD: xform.h,v 1.8 2001/08/28 12:20:43 ben Exp $ */
/*-
* The author of this code is Angelos D. Keromytis (angelos@cis.upenn.edu)
*
* This code was written by Angelos D. Keromytis in Athens, Greece, in
* February 2000. Network Security Technologies Inc. (NSTI) kindly
* supported the development of this code.
*
* Copyright (c) 2000 Angelos D. Keromytis
* Copyright (c) 2014 The FreeBSD Foundation
* All rights reserved.
*
* Portions of this software were developed by John-Mark Gurney
* under sponsorship of the FreeBSD Foundation and
* Rubicon Communications, LLC (Netgate).
*
* Permission to use, copy, and modify this software without fee
* is hereby granted, provided that this entire notice is included in
* all source code copies of any software which is or includes a copy or
* modification of this software.
*
* THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
* REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
* MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
* PURPOSE.
*/
#ifndef _CRYPTO_XFORM_ENC_H_
#define _CRYPTO_XFORM_ENC_H_
#include <sys/malloc.h>
#include <sys/errno.h>
#include <crypto/rijndael/rijndael.h>
#include <crypto/camellia/camellia.h>
#include <opencrypto/cryptodev.h>
#ifdef _STANDALONE
#include <stand.h>
#endif
#define AESICM_BLOCKSIZE AES_BLOCK_LEN
#define AES_XTS_BLOCKSIZE 16
#define AES_XTS_IVSIZE 8
#define AES_XTS_ALPHA 0x87 /* GF(2^128) generator polynomial */
/* Declarations */
struct enc_xform {
int type;
char *name;
size_t ctxsize;
u_int16_t blocksize; /* Required input block size -- 1 for stream ciphers. */
uint16_t native_blocksize; /* Used for stream ciphers. */
u_int16_t ivsize;
u_int16_t minkey, maxkey;
/*
* Encrypt/decrypt a single block. For stream ciphers this
* encrypts/decrypts a single "native" block.
*/
void (*encrypt) (void *, const uint8_t *, uint8_t *);
void (*decrypt) (void *, const uint8_t *, uint8_t *);
int (*setkey) (void *, const uint8_t *, int len);
void (*reinit) (void *, const u_int8_t *);
/*
* For stream ciphers, encrypt/decrypt the final partial block
* of 'len' bytes.
*/
void (*encrypt_last) (void *, const uint8_t *, uint8_t *, size_t len);
void (*decrypt_last) (void *, const uint8_t *, uint8_t *, size_t len);
};
extern struct enc_xform enc_xform_null;
extern struct enc_xform enc_xform_rijndael128;
extern struct enc_xform enc_xform_aes_icm;
extern struct enc_xform enc_xform_aes_nist_gcm;
extern struct enc_xform enc_xform_aes_nist_gmac;
extern struct enc_xform enc_xform_aes_xts;
extern struct enc_xform enc_xform_camellia;
extern struct enc_xform enc_xform_chacha20;
extern struct enc_xform enc_xform_ccm;
struct aes_icm_ctx {
u_int32_t ac_ek[4*(RIJNDAEL_MAXNR + 1)];
/* ac_block is initialized to IV */
u_int8_t ac_block[AESICM_BLOCKSIZE];
int ac_nr;
};
struct aes_xts_ctx {
rijndael_ctx key1;
rijndael_ctx key2;
u_int8_t tweak[AES_XTS_BLOCKSIZE];
};
#endif /* _CRYPTO_XFORM_ENC_H_ */