cpython/Modules/_blake2/impl/blake2-impl.h

/*
   BLAKE2 reference source code package - optimized C implementations
  
   Copyright 2012, Samuel Neves <sneves@dei.uc.pt>.  You may use this under the
   terms of the CC0, the OpenSSL Licence, or the Apache Public License 2.0, at
   your option.  The terms of these licenses can be found at:
  
   - CC0 1.0 Universal : http://creativecommons.org/publicdomain/zero/1.0
   - OpenSSL license   : https://www.openssl.org/source/license.html
   - Apache 2.0        : http://www.apache.org/licenses/LICENSE-2.0
  
   More information about the BLAKE2 hash function can be found at
   https://blake2.net.
*/
#pragma once
#ifndef __BLAKE2_IMPL_H__
#define __BLAKE2_IMPL_H__

#include <stdint.h>
#include <string.h>

BLAKE2_LOCAL_INLINE(uint32_t) load32( const void *src )
{
#if defined(NATIVE_LITTLE_ENDIAN)
  uint32_t w;
  memcpy(&w, src, sizeof w);
  return w;
#else
  const uint8_t *p = ( const uint8_t * )src;
  uint32_t w = *p++;
  w |= ( uint32_t )( *p++ ) <<  8;
  w |= ( uint32_t )( *p++ ) << 16;
  w |= ( uint32_t )( *p++ ) << 24;
  return w;
#endif
}

BLAKE2_LOCAL_INLINE(uint64_t) load64( const void *src )
{
#if defined(NATIVE_LITTLE_ENDIAN)
  uint64_t w;
  memcpy(&w, src, sizeof w);
  return w;
#else
  const uint8_t *p = ( const uint8_t * )src;
  uint64_t w = *p++;
  w |= ( uint64_t )( *p++ ) <<  8;
  w |= ( uint64_t )( *p++ ) << 16;
  w |= ( uint64_t )( *p++ ) << 24;
  w |= ( uint64_t )( *p++ ) << 32;
  w |= ( uint64_t )( *p++ ) << 40;
  w |= ( uint64_t )( *p++ ) << 48;
  w |= ( uint64_t )( *p++ ) << 56;
  return w;
#endif
}

BLAKE2_LOCAL_INLINE(void) store32( void *dst, uint32_t w )
{
#if defined(NATIVE_LITTLE_ENDIAN)
  memcpy(dst, &w, sizeof w);
#else
  uint8_t *p = ( uint8_t * )dst;
  *p++ = ( uint8_t )w; w >>= 8;
  *p++ = ( uint8_t )w; w >>= 8;
  *p++ = ( uint8_t )w; w >>= 8;
  *p++ = ( uint8_t )w;
#endif
}

BLAKE2_LOCAL_INLINE(void) store64( void *dst, uint64_t w )
{
#if defined(NATIVE_LITTLE_ENDIAN)
  memcpy(dst, &w, sizeof w);
#else
  uint8_t *p = ( uint8_t * )dst;
  *p++ = ( uint8_t )w; w >>= 8;
  *p++ = ( uint8_t )w; w >>= 8;
  *p++ = ( uint8_t )w; w >>= 8;
  *p++ = ( uint8_t )w; w >>= 8;
  *p++ = ( uint8_t )w; w >>= 8;
  *p++ = ( uint8_t )w; w >>= 8;
  *p++ = ( uint8_t )w; w >>= 8;
  *p++ = ( uint8_t )w;
#endif
}

BLAKE2_LOCAL_INLINE(uint64_t) load48( const void *src )
{
  const uint8_t *p = ( const uint8_t * )src;
  uint64_t w = *p++;
  w |= ( uint64_t )( *p++ ) <<  8;
  w |= ( uint64_t )( *p++ ) << 16;
  w |= ( uint64_t )( *p++ ) << 24;
  w |= ( uint64_t )( *p++ ) << 32;
  w |= ( uint64_t )( *p++ ) << 40;
  return w;
}

BLAKE2_LOCAL_INLINE(void) store48( void *dst, uint64_t w )
{
  uint8_t *p = ( uint8_t * )dst;
  *p++ = ( uint8_t )w; w >>= 8;
  *p++ = ( uint8_t )w; w >>= 8;
  *p++ = ( uint8_t )w; w >>= 8;
  *p++ = ( uint8_t )w; w >>= 8;
  *p++ = ( uint8_t )w; w >>= 8;
  *p++ = ( uint8_t )w;
}

BLAKE2_LOCAL_INLINE(uint32_t) rotl32( const uint32_t w, const unsigned c )
{
  return ( w << c ) | ( w >> ( 32 - c ) );
}

BLAKE2_LOCAL_INLINE(uint64_t) rotl64( const uint64_t w, const unsigned c )
{
  return ( w << c ) | ( w >> ( 64 - c ) );
}

BLAKE2_LOCAL_INLINE(uint32_t) rotr32( const uint32_t w, const unsigned c )
{
  return ( w >> c ) | ( w << ( 32 - c ) );
}

BLAKE2_LOCAL_INLINE(uint64_t) rotr64( const uint64_t w, const unsigned c )
{
  return ( w >> c ) | ( w << ( 64 - c ) );
}

/* prevents compiler optimizing out memset() */
BLAKE2_LOCAL_INLINE(void) secure_zero_memory(void *v, size_t n)
{
  static void *(*const volatile memset_v)(void *, int, size_t) = &memset;
  memset_v(v, 0, n);
}

#endif