Commit 3919ca29 authored by Niels Möller's avatar Niels Möller

Generalize _ctr_crypt16, so it can be used also for gcm.

parent 1af2ce83
2018-02-01 Niels Möller <nisse@lysator.liu.se>
Based on a patch contributed by Nikos Mavrogiannopoulos.
* ctr16.c (_ctr_crypt16): New file, renamed and generalized
function. New function pointer argument, used to fill a block with
counter values. Use nettle_block16 * as the type for the buffer to
be filled. Always process any final and partial block, and return
no value.
* ctr.c (ctr_crypt): ... previous, replaced, function.
(ctr_fill16): Updated to new argument type.
(ctr_crypt): Return immediately after using _ctr_crypt16.
* ctr-internal.h: New file, declaring _ctr_crypt16.
(nettle_fill16_func): New function typedef.
* Makefile.in (nettle_SOURCES): Added ctr16.c.
(DISTFILES): Added ctr-internal.h.
2018-01-30 Niels Möller <nisse@lysator.liu.se>
* Makefile.in (clean-here): Don't delete desdata.stamp.
......
......@@ -92,7 +92,7 @@ nettle_SOURCES = aes-decrypt-internal.c aes-decrypt.c \
chacha-crypt.c chacha-core-internal.c \
chacha-poly1305.c chacha-poly1305-meta.c \
chacha-set-key.c chacha-set-nonce.c \
ctr.c des.c des3.c des-compat.c \
ctr.c ctr16.c des.c des3.c des-compat.c \
eax.c eax-aes128.c eax-aes128-meta.c \
gcm.c gcm-aes.c \
gcm-aes128.c gcm-aes128-meta.c \
......@@ -225,6 +225,7 @@ DISTFILES = $(SOURCES) $(HEADERS) getopt.h getopt_int.h \
aes-internal.h camellia-internal.h serpent-internal.h \
cast128_sboxes.h desinfo.h desCode.h \
memxor-internal.h nettle-internal.h nettle-write.h \
ctr-internal.h \
gmp-glue.h ecc-internal.h fat-setup.h \
mini-gmp.h asm.m4 \
nettle.texinfo nettle.info nettle.html nettle.pdf sha-example.c
......
/* ctr-internal.h
Copyright (C) 2018 Niels Möller
This file is part of GNU Nettle.
GNU Nettle is free software: you can redistribute it and/or
modify it under the terms of either:
* the GNU Lesser General Public License as published by the Free
Software Foundation; either version 3 of the License, or (at your
option) any later version.
or
* 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.
or both in parallel, as here.
GNU Nettle 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 copies of the GNU General Public License and
the GNU Lesser General Public License along with this program. If
not, see http://www.gnu.org/licenses/.
*/
#ifndef NETTLE_CTR_INTERNAL_H_INCLUDED
#define NETTLE_CTR_INTERNAL_H_INCLUDED
#include "nettle-types.h"
/* Name mangling */
#define _ctr_crypt16 _nettle_ctr_crypt16
/* Size limit for temporary stack buffers. */
#define CTR_BUFFER_LIMIT 512
/* Fill BUFFER (n blocks) with incrementing CTR values. It would be
nice if CTR was always 64-bit aligned, but it isn't when called
from ctr_crypt. */
typedef void
nettle_fill16_func(uint8_t *ctr, size_t n, union nettle_block16 *buffer);
void
_ctr_crypt16(const void *ctx, nettle_cipher_func *f,
nettle_fill16_func *fill, uint8_t *ctr,
size_t length, uint8_t *dst,
const uint8_t *src);
#endif /* NETTLE_CTR_INTERNAL_H_INCLUDED */
......@@ -41,13 +41,11 @@
#include "ctr.h"
#include "ctr-internal.h"
#include "macros.h"
#include "memxor.h"
#include "nettle-internal.h"
/* Don't allocate any more space than this on the stack */
#define CTR_BUFFER_LIMIT 512
#define MIN(a,b) (((a) < (b)) ? (a) : (b))
static size_t
......@@ -64,17 +62,19 @@ ctr_fill (size_t block_size, uint8_t *ctr, size_t length, uint8_t *buffer)
#if WORDS_BIGENDIAN
# define USE_CTR_CRYPT16 1
static nettle_fill16_func ctr_fill16;
static void
ctr_fill16(uint8_t *ctr, size_t blocks, uint64_t *buffer)
ctr_fill16(uint8_t *ctr, size_t blocks, union nettle_block16 *buffer)
{
uint64_t hi, lo;
size_t i;
hi = READ_UINT64(ctr);
lo = READ_UINT64(ctr + 8);
while (blocks-- > 0)
for (i = 0; i < blocks; i++)
{
*buffer++ = hi;
*buffer++ = lo;
buffer[i].u64[0] = hi;
buffer[i].u64[1] = lo;
hi += !(++lo);
}
WRITE_UINT64(ctr, hi);
......@@ -83,18 +83,20 @@ ctr_fill16(uint8_t *ctr, size_t blocks, uint64_t *buffer)
#else /* !WORDS_BIGENDIAN */
# if HAVE_BUILTIN_BSWAP64
# define USE_CTR_CRYPT16 1
static nettle_fill16_func ctr_fill16;
static void
ctr_fill16(uint8_t *ctr, size_t blocks, uint64_t *buffer)
ctr_fill16(uint8_t *ctr, size_t blocks, union nettle_block16 *buffer)
{
uint64_t hi, lo;
size_t i;
/* Read hi in native endianness */
hi = LE_READ_UINT64(ctr);
lo = READ_UINT64(ctr + 8);
while (blocks-- > 0)
for (i = 0; i < blocks; i++)
{
*buffer++ = hi;
*buffer++ = __builtin_bswap64(lo);
buffer[i].u64[0] = hi;
buffer[i].u64[1] = __builtin_bswap64(lo);
if (!++lo)
hi = __builtin_bswap64(__builtin_bswap64(hi) + 1);
}
......@@ -106,53 +108,6 @@ ctr_fill16(uint8_t *ctr, size_t blocks, uint64_t *buffer)
# endif
#endif /* !WORDS_BIGENDIAN */
#if USE_CTR_CRYPT16
static size_t
ctr_crypt16(const void *ctx, nettle_cipher_func *f,
uint8_t *ctr,
size_t length, uint8_t *dst,
const uint8_t *src)
{
if (dst != src && !((uintptr_t) dst % sizeof(uint64_t)))
{
size_t blocks = length / 16u;
ctr_fill16 (ctr, blocks, (uint64_t *) dst);
f(ctx, blocks * 16, dst, dst);
memxor (dst, src, blocks * 16);
return blocks * 16;
}
else
{
/* Construct an aligned buffer of consecutive counter values, of
size at most CTR_BUFFER_LIMIT. */
TMP_DECL(buffer, union nettle_block16, CTR_BUFFER_LIMIT / 16);
size_t blocks = (length + 15) / 16u;
size_t i;
TMP_ALLOC(buffer, MIN(blocks, CTR_BUFFER_LIMIT / 16));
for (i = 0; blocks >= CTR_BUFFER_LIMIT / 16;
i += CTR_BUFFER_LIMIT, blocks -= CTR_BUFFER_LIMIT / 16)
{
ctr_fill16 (ctr, CTR_BUFFER_LIMIT / 16, buffer->u64);
f(ctx, CTR_BUFFER_LIMIT, buffer->b, buffer->b);
if (length - i < CTR_BUFFER_LIMIT)
goto done;
memxor3 (dst, src, buffer->b, CTR_BUFFER_LIMIT);
}
if (blocks > 0)
{
assert (length - i < CTR_BUFFER_LIMIT);
ctr_fill16 (ctr, blocks, buffer->u64);
f(ctx, blocks * 16, buffer->b, buffer->b);
done:
memxor3 (dst + i, src + i, buffer->b, length - i);
}
return length;
}
}
#endif /* USE_CTR_CRYPT16 */
void
ctr_crypt(const void *ctx, nettle_cipher_func *f,
size_t block_size, uint8_t *ctr,
......@@ -162,10 +117,8 @@ ctr_crypt(const void *ctx, nettle_cipher_func *f,
#if USE_CTR_CRYPT16
if (block_size == 16)
{
size_t done = ctr_crypt16(ctx, f, ctr, length, dst, src);
length -= done;
src += done;
dst += done;
_ctr_crypt16(ctx, f, ctr_fill16, ctr, length, dst, src);
return;
}
#endif
......
/* ctr16.c
Cipher counter mode, optimized for 16-byte blocks.
Copyright (C) 2005-2018 Niels Möller
Copyright (C) 2018 Red Hat, Inc.
This file is part of GNU Nettle.
GNU Nettle is free software: you can redistribute it and/or
modify it under the terms of either:
* the GNU Lesser General Public License as published by the Free
Software Foundation; either version 3 of the License, or (at your
option) any later version.
or
* 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.
or both in parallel, as here.
GNU Nettle 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 copies of the GNU General Public License and
the GNU Lesser General Public License along with this program. If
not, see http://www.gnu.org/licenses/.
*/
#if HAVE_CONFIG_H
# include "config.h"
#endif
#include <assert.h>
#include "ctr.h"
#include "ctr-internal.h"
#include "memxor.h"
#include "nettle-internal.h"
#define MIN(a,b) (((a) < (b)) ? (a) : (b))
void
_ctr_crypt16(const void *ctx, nettle_cipher_func *f,
nettle_fill16_func *fill, uint8_t *ctr,
size_t length, uint8_t *dst,
const uint8_t *src)
{
if (dst != src && !((uintptr_t) dst % sizeof(uint64_t)))
{
size_t blocks = length / 16u;
size_t done;
fill (ctr, blocks, (union nettle_block16 *) dst);
done = blocks * 16;
f(ctx, done, dst, dst);
memxor (dst, src, done);
length -= done;
if (length > 0)
{ /* Left-over partial block */
union nettle_block16 block;
dst += done;
src += done;
assert (length < 16);
/* Use fill, to update ctr value in the same way in all cases. */
fill (ctr, 1, &block);
f (ctx, 16, block.b, block.b);
memxor3 (dst, src, block.b, length);
}
}
else
{
/* Construct an aligned buffer of consecutive counter values, of
size at most CTR_BUFFER_LIMIT. */
TMP_DECL(buffer, union nettle_block16, CTR_BUFFER_LIMIT / 16);
size_t blocks = (length + 15) / 16u;
size_t i;
TMP_ALLOC(buffer, MIN(blocks, CTR_BUFFER_LIMIT / 16));
for (i = 0; blocks >= CTR_BUFFER_LIMIT / 16;
i += CTR_BUFFER_LIMIT, blocks -= CTR_BUFFER_LIMIT / 16)
{
fill (ctr, CTR_BUFFER_LIMIT / 16, buffer);
f(ctx, CTR_BUFFER_LIMIT, buffer->b, buffer->b);
if (length - i < CTR_BUFFER_LIMIT)
goto done;
memxor3 (dst, src, buffer->b, CTR_BUFFER_LIMIT);
}
if (blocks > 0)
{
assert (length - i < CTR_BUFFER_LIMIT);
fill (ctr, blocks, buffer);
f(ctx, blocks * 16, buffer->b, buffer->b);
done:
memxor3 (dst + i, src + i, buffer->b, length - i);
}
}
}
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