openssl/crypto/include/internal/chacha.h
Rich Salz 3c27208fab Remove #error from include files.
Don't have #error statements in header files, but instead wrap
the contents of that file in #ifndef OPENSSL_NO_xxx
This means it is now always safe to include the header file.

Reviewed-by: Richard Levitte <levitte@openssl.org>
2016-03-20 19:48:36 -04:00

90 lines
3.7 KiB
C

/* ====================================================================
* Copyright (c) 2014 The OpenSSL Project. 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.
*
* 3. All advertising materials mentioning features or use of this
* software must display the following acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
*
* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For written permission, please contact
* openssl-core@openssl.org.
*
* 5. Products derived from this software may not be called "OpenSSL"
* nor may "OpenSSL" appear in their names without prior written
* permission of the OpenSSL Project.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit (http://www.openssl.org/)"
*
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
* EXPRESSED 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 OpenSSL PROJECT OR
* ITS 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.
* ====================================================================
*
*/
#ifndef HEADER_CHACHA_H
#define HEADER_CHACHA_H
#include <stddef.h>
#ifdef __cplusplus
extern "C" {
#endif
/*
* ChaCha20_ctr32 encrypts |len| bytes from |inp| with the given key and
* nonce and writes the result to |out|, which may be equal to |inp|.
* The |key| is not 32 bytes of verbatim key material though, but the
* said material collected into 8 32-bit elements array in host byte
* order. Same approach applies to nonce: the |counter| argument is
* pointer to concatenated nonce and counter values collected into 4
* 32-bit elements. This, passing crypto material collected into 32-bit
* elements as opposite to passing verbatim byte vectors, is chosen for
* efficiency in multi-call scenarios.
*/
void ChaCha20_ctr32(unsigned char *out, const unsigned char *inp,
size_t len, const unsigned int key[8],
const unsigned int counter[4]);
/*
* You can notice that there is no key setup procedure. Because it's
* as trivial as collecting bytes into 32-bit elements, it's reckoned
* that below macro is sufficient.
*/
#define CHACHA_U8TOU32(p) ( \
((unsigned int)(p)[0]) | ((unsigned int)(p)[1]<<8) | \
((unsigned int)(p)[2]<<16) | ((unsigned int)(p)[3]<<24) )
#define CHACHA_KEY_SIZE 32
#define CHACHA_CTR_SIZE 16
#define CHACHA_BLK_SIZE 64
#ifdef __cplusplus
}
#endif
#endif