pcompress/crypto/scrypt/crypto_aesctr.c
Moinak Ghosh 26bb137257 Changes for generalized runtime SSE/AVX/XOP detection.
Multi instruction set XXhash build with runtime selection.
Extend CPUID code to detect more instruction sets.
Add options for BLAKE2 hash.
Move GCC builtins into utils header.
Bump file format version number due to extended digest flags.
Add descriptions to digest list.
2013-01-25 00:10:12 +05:30

150 lines
4.2 KiB
C

/*-
* Copyright 2007-2009 Colin Percival
* All rights reserved.
*
* 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.
*
* This file was originally written by Colin Percival as part of the Tarsnap
* online backup system.
*/
#include <stdint.h>
#include <stdlib.h>
#include <openssl/aes.h>
#ifdef __USE_SSE_INTRIN__
#include <emmintrin.h>
#endif
#include <utils.h>
#include "crypto_aesctr.h"
struct crypto_aesctr {
AES_KEY * key;
uint64_t nonce;
uint64_t bytectr;
uint8_t buf[16] __attribute__((aligned(16)));
};
/**
* crypto_aesctr_init(key, nonce):
* Prepare to encrypt/decrypt data with AES in CTR mode, using the provided
* expanded key and nonce. The key provided must remain valid for the
* lifetime of the stream.
*/
struct crypto_aesctr *
crypto_aesctr_init(AES_KEY * key, uint64_t nonce)
{
struct crypto_aesctr * stream;
/* Allocate memory. */
if ((stream = (struct crypto_aesctr *)malloc(sizeof(struct crypto_aesctr))) == NULL)
goto err0;
/* Initialize values. */
stream->key = key;
stream->nonce = nonce;
stream->bytectr = 0;
/* Success! */
return (stream);
err0:
/* Failure! */
return (NULL);
}
/**
* crypto_aesctr_stream(stream, inbuf, outbuf, buflen):
* Generate the next ${buflen} bytes of the AES-CTR stream and xor them with
* bytes from ${inbuf}, writing the result into ${outbuf}. If the buffers
* ${inbuf} and ${outbuf} overlap, they must be identical.
*/
void
crypto_aesctr_stream(struct crypto_aesctr * stream, const uint8_t * inbuf,
uint8_t * outbuf, size_t buflen)
{
uint8_t pblk[16];
size_t pos;
int bytemod, last;
last = 0;
pos = 0;
*((uint64_t *)pblk) = htonll(stream->nonce);
do_last:
for (; pos < buflen; pos++) {
/* How far through the buffer are we? */
bytemod = stream->bytectr & (16 - 1);
/* Generate a block of cipherstream if needed. */
if (bytemod == 0) {
*((uint64_t *)(pblk + 8)) = htonll(stream->bytectr / 16);
AES_encrypt(pblk, stream->buf, stream->key);
#ifdef __USE_SSE_INTRIN__
if (!last)
break;
#endif
}
/* Encrypt a byte. */
outbuf[pos] = inbuf[pos] ^ stream->buf[bytemod];
/* Move to the next byte of cipherstream. */
stream->bytectr += 1;
}
#ifdef __USE_SSE_INTRIN__
if (last) return;
for (; pos < buflen-15; pos += 16) {
__m128i cblk, dat, odat;
PREFETCH_WRITE(outbuf+pos, 0);
PREFETCH_READ(inbuf+pos, 0);
cblk = _mm_load_si128((__m128i *)(stream->buf));
dat = _mm_loadu_si128((__m128i *)(inbuf+pos));
odat = _mm_xor_si128(cblk, dat);
_mm_storeu_si128((__m128i *)(outbuf+pos), odat);
stream->bytectr += 16;
*((uint64_t *)(pblk + 8)) = htonll(stream->bytectr / 16);
AES_encrypt(pblk, stream->buf, stream->key);
}
last = 1;
goto do_last;
#endif
}
/**
* crypto_aesctr_free(stream):
* Free the provided stream object.
*/
void
crypto_aesctr_free(struct crypto_aesctr * stream)
{
int i;
/* Zero potentially sensitive information. */
for (i = 0; i < 16; i++)
stream->buf[i] = 0;
stream->bytectr = stream->nonce = 0;
/* Free the stream. */
free(stream);
}