/*
 ---------------------------------------------------------------------------
 Copyright (c) 2002, Dr Brian Gladman <brg@gladman.me.uk>, Worcester, UK.
 All rights reserved.

 LICENSE TERMS

 The free distribution and use of this software in both source and binary 
 form is allowed (with or without changes) provided that:

   1. distributions of this source code include the above copyright 
      notice, this list of conditions and the following disclaimer;

   2. distributions in binary form include the above copyright
      notice, this list of conditions and the following disclaimer
      in the documentation and/or other associated materials;

   3. the copyright holder's name is not used to endorse products 
      built using this software without specific written permission. 

 ALTERNATIVELY, provided that this notice is retained in full, this product
 may be distributed under the terms of the GNU General Public License (GPL),
 in which case the provisions of the GPL apply INSTEAD OF those given above.
 
 DISCLAIMER

 This software is provided 'as is' with no explicit or implied warranties
 in respect of its properties, including, but not limited to, correctness 
 and/or fitness for purpose.
 ---------------------------------------------------------------------------
 Issue Date: 26/08/2003
*/

#ifndef _SHA2_H
#define _SHA2_H

#include <limits.h>

/*  Defines for suffixes to 32 and 64 bit unsigned numeric values   */

#define sfx_lo(x,y) x##y
#define sfx_hi(x,y) sfx_lo(x,y)
#define n_u32(p)    sfx_hi(0x##p,s_u32)
#define n_u64(p)    sfx_hi(0x##p,s_u64)

/* define an unsigned 32-bit type */

#if UINT_MAX == 0xffffffff
  typedef   unsigned int     sha2_32t;
  #define s_u32    u
#elif ULONG_MAX == 0xffffffff
  typedef   unsigned long    sha2_32t;
  #define s_u32   ul
#else
#error Please define sha2_32t as an unsigned 32 bit type in sha2.h
#endif

/* define an unsigned 64-bit type */

#if _MSC_VER < 1300
  typedef unsigned __int64   sha2_64t;
  #define s_u64 ui64
#elif ULONG_MAX == 0xffffffffffffffff
  typedef unsigned long      sha2_64t;
  #define s_u64   ul
#elif ULONG_MAX == 0xffffffff
  typedef unsigned long long sha2_64t;   /* a somewhat dangerous guess */
  #define s_u64  ull
#else
#error Please define sha2_64t as an unsigned 64 bit type in sha2.h
#endif

#if defined(__cplusplus)
extern "C"
{
#endif

#define SHA256_DIGEST_SIZE  32
#define SHA384_DIGEST_SIZE  48
#define SHA512_DIGEST_SIZE  64

#define SHA256_BLOCK_SIZE   64
#define SHA384_BLOCK_SIZE  128
#define SHA512_BLOCK_SIZE  128

#define SHA2_MAX_DIGEST_SIZE    SHA512_DIGEST_SIZE

#define SHA2_GOOD   0
#define SHA2_BAD    1

/* type to hold the SHA256 context              */

typedef struct
{   sha2_32t count[2];
    sha2_32t hash[8];
    sha2_32t wbuf[16];
} sha256_ctx;

/* type to hold the SHA384/512 context          */

typedef struct
{   sha2_64t count[2];
    sha2_64t hash[8];
    sha2_64t wbuf[16];
} sha512_ctx;

typedef sha512_ctx  sha384_ctx;

/* type to hold a SHA2 context (256/384/512)  */

typedef struct
{   union
    {   sha256_ctx  ctx256[1];
        sha512_ctx  ctx512[1];
    } uu[1];
    sha2_32t    sha2_len;
} sha2_ctx;

#ifndef SHA2_DLL                  /* implement normal or DLL functions   */
#define sha2_void   void
#define sha2_int    int
#else
#define sha2_void   void __declspec(dllexport) _stdcall
#define sha2_int    int  __declspec(dllexport) _stdcall
#endif

sha2_void sha256_compile(sha256_ctx ctx[1]);
sha2_void sha512_compile(sha512_ctx ctx[1]);

sha2_void sha256_begin(sha256_ctx ctx[1]);
sha2_void sha256_hash(const unsigned char data[], unsigned long len, sha256_ctx ctx[1]);
sha2_void sha256_end(unsigned char hval[], sha256_ctx ctx[1]);
sha2_void sha256(unsigned char hval[], const unsigned char data[], unsigned long len); 

sha2_void sha384_begin(sha384_ctx ctx[1]);
#define sha384_hash sha512_hash
sha2_void sha384_end(unsigned char hval[], sha384_ctx ctx[1]);
sha2_void sha384(unsigned char hval[], const unsigned char data[], unsigned long len); 

sha2_void sha512_begin(sha512_ctx ctx[1]);
sha2_void sha512_hash(const unsigned char data[], unsigned long len, sha512_ctx ctx[1]);
sha2_void sha512_end(unsigned char hval[], sha512_ctx ctx[1]);
sha2_void sha512(unsigned char hval[], const unsigned char data[], unsigned long len); 

sha2_int  sha2_begin(unsigned long size, sha2_ctx ctx[1]);
sha2_void sha2_hash(const unsigned char data[], unsigned long len, sha2_ctx ctx[1]);
sha2_void sha2_end(unsigned char hval[], sha2_ctx ctx[1]);
sha2_int  sha2(unsigned char hval[], unsigned long size, const unsigned char data[], unsigned long len); 

#if defined(__cplusplus)
}
#endif

#endif
