/*
 ---------------------------------------------------------------------------
 Copyright (c) 2002, Dr Brian Gladman, Worcester, UK.   All rights reserved.

 LICENSE TERMS

 The free distribution and use of this software is allowed (with or without
 changes) provided that:

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

  2. binary distributions include the above copyright notice, this list
     of conditions and the following disclaimer in their documentation;

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

 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: 01/08/2005

 This is a byte oriented version of SHA2 that operates on arrays of bytes
 stored in memory. This code implements sha256, sha384 and sha512 but the
 latter two functions rely on efficient 64-bit integer operations that
 may not be very efficient on 32-bit machines

 The sha256 functions use a type 'sha256_ctx' to hold details of the
 current hash state and uses the following three calls:

       void sha256_begin(sha256_ctx ctx[1])
       void sha256_hash(const unsigned char data[],
                            unsigned long len, sha256_ctx ctx[1])
       void sha_end1(unsigned char hval[], sha256_ctx ctx[1])

 The first subroutine initialises a hash computation by setting up the
 context in the sha256_ctx context. The second subroutine hashes 8-bit
 bytes from array data[] into the hash state withinh sha256_ctx context,
 the number of bytes to be hashed being given by the the unsigned long
 integer len.  The third subroutine completes the hash calculation and
 places the resulting digest value in the array of 8-bit bytes hval[].

 The sha384 and sha512 functions are similar and use the interfaces:

       void sha384_begin(sha384_ctx ctx[1]);
       void sha384_hash(const unsigned char data[],
                            unsigned long len, sha384_ctx ctx[1]);
       void sha384_end(unsigned char hval[], sha384_ctx ctx[1]);

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

 In addition there is a function sha2 that can be used to call all these
 functions using a call with a hash length parameter as follows:

       int sha2_begin(unsigned long len, sha2_ctx ctx[1]);
       void sha2_hash(const unsigned char data[],
                            unsigned long len, sha2_ctx ctx[1]);
       void sha2_end(unsigned char hval[], sha2_ctx ctx[1]);

 My thanks to Erik Andersen <andersen@codepoet.org> for testing this code
 on big-endian systems and for his assistance with corrections
*/

#include "Common/Endian.h"
#include "Common/Tcdefs.h"
#include "Crypto/misc.h"

#define PLATFORM_BYTE_ORDER BYTE_ORDER
#define IS_LITTLE_ENDIAN LITTLE_ENDIAN

#if 0
#define UNROLL_SHA2     /* for SHA2 loop unroll     */
#endif

#if !defined(_UEFI)
#include <string.h>     /* for memcpy() etc.        */
#endif // !defined(_UEFI)

#include "Sha2.h"

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

#if defined( _MSC_VER ) && ( _MSC_VER > 800 ) && !defined(_UEFI)
#pragma intrinsic(memcpy)
#endif

#if (PLATFORM_BYTE_ORDER == IS_LITTLE_ENDIAN)
#define SWAP_BYTES
#else
#undef  SWAP_BYTES
#endif

#if 0

#define ch(x,y,z)       (((x) & (y)) ^ (~(x) & (z)))
#define maj(x,y,z)      (((x) & (y)) ^ ((x) & (z)) ^ ((y) & (z)))

#else   /* Thanks to Rich Schroeppel and Colin Plumb for the following      */

#define ch(x,y,z)       ((z) ^ ((x) & ((y) ^ (z))))
#define maj(x,y,z)      (((x) & (y)) | ((z) & ((x) ^ (y))))

#endif

/* round transforms for SHA256 and SHA512 compression functions */

#define vf(n,i) v[(n - i) & 7]

#define hf(i) (p[i & 15] += \
    g_1(p[(i + 14) & 15]) + p[(i + 9) & 15] + g_0(p[(i + 1) & 15]))

#define v_cycle(i,j)                                \
    vf(7,i) += (j ? hf(i) : p[i]) + k_0[i+j]        \
    + s_1(vf(4,i)) + ch(vf(4,i),vf(5,i),vf(6,i));   \
    vf(3,i) += vf(7,i);                             \
    vf(7,i) += s_0(vf(0,i))+ maj(vf(0,i),vf(1,i),vf(2,i))

#if defined(SHA_224) || defined(SHA_256)

#define SHA256_MASK (SHA256_BLOCK_SIZE - 1)

#if defined(SWAP_BYTES)
#define bsw_32(p,n) \
    { int _i = (n); while(_i--) ((uint_32t*)p)[_i] = bswap_32(((uint_32t*)p)[_i]); }
#else
#define bsw_32(p,n)
#endif

#define s_0(x)  (rotr32((x),  2) ^ rotr32((x), 13) ^ rotr32((x), 22))
#define s_1(x)  (rotr32((x),  6) ^ rotr32((x), 11) ^ rotr32((x), 25))
#define g_0(x)  (rotr32((x),  7) ^ rotr32((x), 18) ^ ((x) >>  3))
#define g_1(x)  (rotr32((x), 17) ^ rotr32((x), 19) ^ ((x) >> 10))
#define k_0     k256

/* rotated SHA256 round definition. Rather than swapping variables as in    */
/* FIPS-180, different variables are 'rotated' on each round, returning     */
/* to their starting positions every eight rounds                           */

#define q(n)  v##n

#define one_cycle(a,b,c,d,e,f,g,h,k,w)  \
    q(h) += s_1(q(e)) + ch(q(e), q(f), q(g)) + k + w; \
    q(d) += q(h); q(h) += s_0(q(a)) + maj(q(a), q(b), q(c))

/* SHA256 mixing data   */

const uint_32t k256[64] =
{   0x428a2f98ul, 0x71374491ul, 0xb5c0fbcful, 0xe9b5dba5ul,
    0x3956c25bul, 0x59f111f1ul, 0x923f82a4ul, 0xab1c5ed5ul,
    0xd807aa98ul, 0x12835b01ul, 0x243185beul, 0x550c7dc3ul,
    0x72be5d74ul, 0x80deb1feul, 0x9bdc06a7ul, 0xc19bf174ul,
    0xe49b69c1ul, 0xefbe4786ul, 0x0fc19dc6ul, 0x240ca1ccul,
    0x2de92c6ful, 0x4a7484aaul, 0x5cb0a9dcul, 0x76f988daul,
    0x983e5152ul, 0xa831c66dul, 0xb00327c8ul, 0xbf597fc7ul,
    0xc6e00bf3ul, 0xd5a79147ul, 0x06ca6351ul, 0x14292967ul,
    0x27b70a85ul, 0x2e1b2138ul, 0x4d2c6dfcul, 0x53380d13ul,
    0x650a7354ul, 0x766a0abbul, 0x81c2c92eul, 0x92722c85ul,
    0xa2bfe8a1ul, 0xa81a664bul, 0xc24b8b70ul, 0xc76c51a3ul,
    0xd192e819ul, 0xd6990624ul, 0xf40e3585ul, 0x106aa070ul,
    0x19a4c116ul, 0x1e376c08ul, 0x2748774cul, 0x34b0bcb5ul,
    0x391c0cb3ul, 0x4ed8aa4aul, 0x5b9cca4ful, 0x682e6ff3ul,
    0x748f82eeul, 0x78a5636ful, 0x84c87814ul, 0x8cc70208ul,
    0x90befffaul, 0xa4506cebul, 0xbef9a3f7ul, 0xc67178f2ul,
};

/* Compile 64 bytes of hash data into SHA256 digest value   */
/* NOTE: this routine assumes that the byte order in the    */
/* ctx->wbuf[] at this point is such that low address bytes */
/* in the ORIGINAL byte stream will go into the high end of */
/* words on BOTH big and little endian systems              */

VOID_RETURN sha256_compile(sha256_ctx ctx[1])
{
#if !defined(UNROLL_SHA2)

    uint_32t j, *p = ctx->wbuf, v[8];

    memcpy(v, ctx->hash, 8 * sizeof(uint_32t));

    for(j = 0; j < 64; j += 16)
    {
        v_cycle( 0, j); v_cycle( 1, j);
        v_cycle( 2, j); v_cycle( 3, j);
        v_cycle( 4, j); v_cycle( 5, j);
        v_cycle( 6, j); v_cycle( 7, j);
        v_cycle( 8, j); v_cycle( 9, j);
        v_cycle(10, j); v_cycle(11, j);
        v_cycle(12, j); v_cycle(13, j);
        v_cycle(14, j); v_cycle(15, j);
    }

    ctx->hash[0] += v[0]; ctx->hash[1] += v[1];
    ctx->hash[2] += v[2]; ctx->hash[3] += v[3];
    ctx->hash[4] += v[4]; ctx->hash[5] += v[5];
    ctx->hash[6] += v[6]; ctx->hash[7] += v[7];

#else

    uint_32t *p = ctx->wbuf,v0,v1,v2,v3,v4,v5,v6,v7;

    v0 = ctx->hash[0]; v1 = ctx->hash[1];
    v2 = ctx->hash[2]; v3 = ctx->hash[3];
    v4 = ctx->hash[4]; v5 = ctx->hash[5];
    v6 = ctx->hash[6]; v7 = ctx->hash[7];

    one_cycle(0,1,2,3,4,5,6,7,k256[ 0],p[ 0]);
    one_cycle(7,0,1,2,3,4,5,6,k256[ 1],p[ 1]);
    one_cycle(6,7,0,1,2,3,4,5,k256[ 2],p[ 2]);
    one_cycle(5,6,7,0,1,2,3,4,k256[ 3],p[ 3]);
    one_cycle(4,5,6,7,0,1,2,3,k256[ 4],p[ 4]);
    one_cycle(3,4,5,6,7,0,1,2,k256[ 5],p[ 5]);
    one_cycle(2,3,4,5,6,7,0,1,k256[ 6],p[ 6]);
    one_cycle(1,2,3,4,5,6,7,0,k256[ 7],p[ 7]);
    one_cycle(0,1,2,3,4,5,6,7,k256[ 8],p[ 8]);
    one_cycle(7,0,1,2,3,4,5,6,k256[ 9],p[ 9]);
    one_cycle(6,7,0,1,2,3,4,5,k256[10],p[10]);
    one_cycle(5,6,7,0,1,2,3,4,k256[11],p[11]);
    one_cycle(4,5,6,7,0,1,2,3,k256[12],p[12]);
    one_cycle(3,4,5,6,7,0,1,2,k256[13],p[13]);
    one_cycle(2,3,4,5,6,7,0,1,k256[14],p[14]);
    one_cycle(1,2,3,4,5,6,7,0,k256[15],p[15]);

    one_cycle(0,1,2,3,4,5,6,7,k256[16],hf( 0));
    one_cycle(7,0,1,2,3,4,5,6,k256[17],hf( 1));
    one_cycle(6,7,0,1,2,3,4,5,k256[18],hf( 2));
    one_cycle(5,6,7,0,1,2,3,4,k256[19],hf( 3));
    one_cycle(4,5,6,7,0,1,2,3,k256[20],hf( 4));
    one_cycle(3,4,5,6,7,0,1,2,k256[21],hf( 5));
    one_cycle(2,3,4,5,6,7,0,1,k256[22],hf( 6));
    one_cycle(1,2,3,4,5,6,7,0,k256[23],hf( 7));
    one_cycle(0,1,2,3,4,5,6,7,k256[24],hf( 8));
    one_cycle(7,0,1,2,3,4,5,6,k256[25],hf( 9));
    one_cycle(6,7,0,1,2,3,4,5,k256[26],hf(10));
    one_cycle(5,6,7,0,1,2,3,4,k256[27],hf(11));
    one_cycle(4,5,6,7,0,1,2,3,k256[28],hf(12));
    one_cycle(3,4,5,6,7,0,1,2,k256[29],hf(13));
    one_cycle(2,3,4,5,6,7,0,1,k256[30],hf(14));
    one_cycle(1,2,3,4,5,6,7,0,k256[31],hf(15));

    one_cycle(0,1,2,3,4,5,6,7,k256[32],hf( 0));
    one_cycle(7,0,1,2,3,4,5,6,k256[33],hf( 1));
    one_cycle(6,7,0,1,2,3,4,5,k256[34],hf( 2));
    one_cycle(5,6,7,0,1,2,3,4,k256[35],hf( 3));
    one_cycle(4,5,6,7,0,1,2,3,k256[36],hf( 4));
    one_cycle(3,4,5,6,7,0,1,2,k256[37],hf( 5));
    one_cycle(2,3,4,5,6,7,0,1,k256[38],hf( 6));
    one_cycle(1,2,3,4,5,6,7,0,k256[39],hf( 7));
    one_cycle(0,1,2,3,4,5,6,7,k256[40],hf( 8));
    one_cycle(7,0,1,2,3,4,5,6,k256[41],hf( 9));
    one_cycle(6,7,0,1,2,3,4,5,k256[42],hf(10));
    one_cycle(5,6,7,0,1,2,3,4,k256[43],hf(11));
    one_cycle(4,5,6,7,0,1,2,3,k256[44],hf(12));
    one_cycle(3,4,5,6,7,0,1,2,k256[45],hf(13));
    one_cycle(2,3,4,5,6,7,0,1,k256[46],hf(14));
    one_cycle(1,2,3,4,5,6,7,0,k256[47],hf(15));

    one_cycle(0,1,2,3,4,5,6,7,k256[48],hf( 0));
    one_cycle(7,0,1,2,3,4,5,6,k256[49],hf( 1));
    one_cycle(6,7,0,1,2,3,4,5,k256[50],hf( 2));
    one_cycle(5,6,7,0,1,2,3,4,k256[51],hf( 3));
    one_cycle(4,5,6,7,0,1,2,3,k256[52],hf( 4));
    one_cycle(3,4,5,6,7,0,1,2,k256[53],hf( 5));
    one_cycle(2,3,4,5,6,7,0,1,k256[54],hf( 6));
    one_cycle(1,2,3,4,5,6,7,0,k256[55],hf( 7));
    one_cycle(0,1,2,3,4,5,6,7,k256[56],hf( 8));
    one_cycle(7,0,1,2,3,4,5,6,k256[57],hf( 9));
    one_cycle(6,7,0,1,2,3,4,5,k256[58],hf(10));
    one_cycle(5,6,7,0,1,2,3,4,k256[59],hf(11));
    one_cycle(4,5,6,7,0,1,2,3,k256[60],hf(12));
    one_cycle(3,4,5,6,7,0,1,2,k256[61],hf(13));
    one_cycle(2,3,4,5,6,7,0,1,k256[62],hf(14));
    one_cycle(1,2,3,4,5,6,7,0,k256[63],hf(15));

    ctx->hash[0] += v0; ctx->hash[1] += v1;
    ctx->hash[2] += v2; ctx->hash[3] += v3;
    ctx->hash[4] += v4; ctx->hash[5] += v5;
    ctx->hash[6] += v6; ctx->hash[7] += v7;
#endif
}

/* SHA256 hash data in an array of bytes into hash buffer   */
/* and call the hash_compile function as required.          */

VOID_RETURN sha256_hash(const unsigned char data[], unsigned long len, sha256_ctx ctx[1])
{   uint_32t pos = (uint_32t)(ctx->count[0] & SHA256_MASK),
             space = SHA256_BLOCK_SIZE - pos;
    const unsigned char *sp = data;

    if((ctx->count[0] += len) < len)
        ++(ctx->count[1]);

    while(len >= space)     /* tranfer whole blocks while possible  */
    {
        memcpy(((unsigned char*)ctx->wbuf) + pos, sp, space);
        sp += space; len -= space; space = SHA256_BLOCK_SIZE; pos = 0;
        bsw_32(ctx->wbuf, SHA256_BLOCK_SIZE >> 2)
        sha256_compile(ctx);
    }

    memcpy(((unsigned char*)ctx->wbuf) + pos, sp, len);
}

/* SHA256 Final padding and digest calculation  */

static void sha_end1(unsigned char hval[], sha256_ctx ctx[1], const unsigned int hlen)
{   uint_32t    i = (uint_32t)(ctx->count[0] & SHA256_MASK);

    /* put bytes in the buffer in an order in which references to   */
    /* 32-bit words will put bytes with lower addresses into the    */
    /* top of 32 bit words on BOTH big and little endian machines   */
    bsw_32(ctx->wbuf, (i + 3) >> 2)

    /* we now need to mask valid bytes and add the padding which is */
    /* a single 1 bit and as many zero bits as necessary. Note that */
    /* we can always add the first padding byte here because the    */
    /* buffer always has at least one empty slot                    */
    ctx->wbuf[i >> 2] &= 0xffffff80 << 8 * (~i & 3);
    ctx->wbuf[i >> 2] |= 0x00000080 << 8 * (~i & 3);

    /* we need 9 or more empty positions, one for the padding byte  */
    /* (above) and eight for the length count.  If there is not     */
    /* enough space pad and empty the buffer                        */
    if(i > SHA256_BLOCK_SIZE - 9)
    {
        if(i < 60) ctx->wbuf[15] = 0;
        sha256_compile(ctx);
        i = 0;
    }
    else    /* compute a word index for the empty buffer positions  */
        i = (i >> 2) + 1;

    while(i < 14) /* and zero pad all but last two positions        */
        ctx->wbuf[i++] = 0;

    /* the following 32-bit length fields are assembled in the      */
    /* wrong byte order on little endian machines but this is       */
    /* corrected later since they are only ever used as 32-bit      */
    /* word values.                                                 */
    ctx->wbuf[14] = (ctx->count[1] << 3) | (ctx->count[0] >> 29);
    ctx->wbuf[15] = ctx->count[0] << 3;
    sha256_compile(ctx);

    /* extract the hash value as bytes in case the hash buffer is   */
    /* mislaigned for 32-bit words                                  */
    for(i = 0; i < hlen; ++i)
        hval[i] = (unsigned char)(ctx->hash[i >> 2] >> (8 * (~i & 3)));
}

#endif

#if defined(SHA_224)

const uint_32t i224[8] =
{
    0xc1059ed8ul, 0x367cd507ul, 0x3070dd17ul, 0xf70e5939ul,
    0xffc00b31ul, 0x68581511ul, 0x64f98fa7ul, 0xbefa4fa4ul
};

VOID_RETURN sha224_begin(sha224_ctx ctx[1])
{
    ctx->count[0] = ctx->count[1] = 0;
    memcpy(ctx->hash, i224, 8 * sizeof(uint_32t));
}

VOID_RETURN sha224_end(unsigned char hval[], sha224_ctx ctx[1])
{
    sha_end1(hval, ctx, SHA224_DIGEST_SIZE);
}

VOID_RETURN sha224(unsigned char hval[], const unsigned char data[], unsigned long len)
{   sha224_ctx  cx[1];

    sha224_begin(cx);
    sha224_hash(data, len, cx);
    sha_end1(hval, cx, SHA224_DIGEST_SIZE);
}

#endif

#if defined(SHA_256)

const uint_32t i256[8] =
{
    0x6a09e667ul, 0xbb67ae85ul, 0x3c6ef372ul, 0xa54ff53aul,
    0x510e527ful, 0x9b05688cul, 0x1f83d9abul, 0x5be0cd19ul
};

VOID_RETURN sha256_begin(sha256_ctx ctx[1])
{
    ctx->count[0] = ctx->count[1] = 0;
    memcpy(ctx->hash, i256, 8 * sizeof(uint_32t));
}

VOID_RETURN sha256_end(unsigned char hval[], sha256_ctx ctx[1])
{
    sha_end1(hval, ctx, SHA256_DIGEST_SIZE);
}

VOID_RETURN sha256(unsigned char hval[], const unsigned char data[], unsigned long len)
{   sha256_ctx  cx[1];

    sha256_begin(cx);
    sha256_hash(data, len, cx);
    sha_end1(hval, cx, SHA256_DIGEST_SIZE);
}

#endif

#if defined(SHA_384) || defined(SHA_512)

#define SHA512_MASK (SHA512_BLOCK_SIZE - 1)

#if defined(SWAP_BYTES)
#define bsw_64(p,n) \
    { int _i = (n); while(_i--) ((uint_64t*)p)[_i] = bswap_64(((uint_64t*)p)[_i]); }
#else
#define bsw_64(p,n)
#endif

/* SHA512 mixing function definitions   */

#ifdef   s_0
# undef  s_0
# undef  s_1
# undef  g_0
# undef  g_1
# undef  k_0
#endif

#define s_0(x)  (rotr64((x), 28) ^ rotr64((x), 34) ^ rotr64((x), 39))
#define s_1(x)  (rotr64((x), 14) ^ rotr64((x), 18) ^ rotr64((x), 41))
#define g_0(x)  (rotr64((x),  1) ^ rotr64((x),  8) ^ ((x) >>  7))
#define g_1(x)  (rotr64((x), 19) ^ rotr64((x), 61) ^ ((x) >>  6))
#define k_0     k512

/* SHA384/SHA512 mixing data    */

const uint_64t  k512[80] =
{
    li_64(428a2f98d728ae22), li_64(7137449123ef65cd),
    li_64(b5c0fbcfec4d3b2f), li_64(e9b5dba58189dbbc),
    li_64(3956c25bf348b538), li_64(59f111f1b605d019),
    li_64(923f82a4af194f9b), li_64(ab1c5ed5da6d8118),
    li_64(d807aa98a3030242), li_64(12835b0145706fbe),
    li_64(243185be4ee4b28c), li_64(550c7dc3d5ffb4e2),
    li_64(72be5d74f27b896f), li_64(80deb1fe3b1696b1),
    li_64(9bdc06a725c71235), li_64(c19bf174cf692694),
    li_64(e49b69c19ef14ad2), li_64(efbe4786384f25e3),
    li_64(0fc19dc68b8cd5b5), li_64(240ca1cc77ac9c65),
    li_64(2de92c6f592b0275), li_64(4a7484aa6ea6e483),
    li_64(5cb0a9dcbd41fbd4), li_64(76f988da831153b5),
    li_64(983e5152ee66dfab), li_64(a831c66d2db43210),
    li_64(b00327c898fb213f), li_64(bf597fc7beef0ee4),
    li_64(c6e00bf33da88fc2), li_64(d5a79147930aa725),
    li_64(06ca6351e003826f), li_64(142929670a0e6e70),
    li_64(27b70a8546d22ffc), li_64(2e1b21385c26c926),
    li_64(4d2c6dfc5ac42aed), li_64(53380d139d95b3df),
    li_64(650a73548baf63de), li_64(766a0abb3c77b2a8),
    li_64(81c2c92e47edaee6), li_64(92722c851482353b),
    li_64(a2bfe8a14cf10364), li_64(a81a664bbc423001),
    li_64(c24b8b70d0f89791), li_64(c76c51a30654be30),
    li_64(d192e819d6ef5218), li_64(d69906245565a910),
    li_64(f40e35855771202a), li_64(106aa07032bbd1b8),
    li_64(19a4c116b8d2d0c8), li_64(1e376c085141ab53),
    li_64(2748774cdf8eeb99), li_64(34b0bcb5e19b48a8),
    li_64(391c0cb3c5c95a63), li_64(4ed8aa4ae3418acb),
    li_64(5b9cca4f7763e373), li_64(682e6ff3d6b2b8a3),
    li_64(748f82ee5defb2fc), li_64(78a5636f43172f60),
    li_64(84c87814a1f0ab72), li_64(8cc702081a6439ec),
    li_64(90befffa23631e28), li_64(a4506cebde82bde9),
    li_64(bef9a3f7b2c67915), li_64(c67178f2e372532b),
    li_64(ca273eceea26619c), li_64(d186b8c721c0c207),
    li_64(eada7dd6cde0eb1e), li_64(f57d4f7fee6ed178),
    li_64(06f067aa72176fba), li_64(0a637dc5a2c898a6),
    li_64(113f9804bef90dae), li_64(1b710b35131c471b),
    li_64(28db77f523047d84), li_64(32caab7b40c72493),
    li_64(3c9ebe0a15c9bebc), li_64(431d67c49c100d4c),
    li_64(4cc5d4becb3e42b6), li_64(597f299cfc657e2a),
    li_64(5fcb6fab3ad6faec), li_64(6c44198c4a475817)
};

/* Compile 128 bytes of hash data into SHA384/512 digest    */
/* NOTE: this routine assumes that the byte order in the    */
/* ctx->wbuf[] at this point is such that low address bytes */
/* in the ORIGINAL byte stream will go into the high end of */
/* words on BOTH big and little endian systems              */

VOID_RETURN sha512_compile(sha512_ctx ctx[1])
{   uint_64t    v[8], *p = ctx->wbuf;
    uint_32t    j;

    memcpy(v, ctx->hash, 8 * sizeof(uint_64t));

    for(j = 0; j < 80; j += 16)
    {
        v_cycle( 0, j); v_cycle( 1, j);
        v_cycle( 2, j); v_cycle( 3, j);
        v_cycle( 4, j); v_cycle( 5, j);
        v_cycle( 6, j); v_cycle( 7, j);
        v_cycle( 8, j); v_cycle( 9, j);
        v_cycle(10, j); v_cycle(11, j);
        v_cycle(12, j); v_cycle(13, j);
        v_cycle(14, j); v_cycle(15, j);
    }

    ctx->hash[0] += v[0]; ctx->hash[1] += v[1];
    ctx->hash[2] += v[2]; ctx->hash[3] += v[3];
    ctx->hash[4] += v[4]; ctx->hash[5] += v[5];
    ctx->hash[6] += v[6]; ctx->hash[7] += v[7];
}

/* Compile 128 bytes of hash data into SHA256 digest value  */
/* NOTE: this routine assumes that the byte order in the    */
/* ctx->wbuf[] at this point is in such an order that low   */
/* address bytes in the ORIGINAL byte stream placed in this */
/* buffer will now go to the high end of words on BOTH big  */
/* and little endian systems                                */

VOID_RETURN sha512_hash(const unsigned char data[], unsigned long len, sha512_ctx ctx[1])
{   uint_32t pos = (uint_32t)(ctx->count[0] & SHA512_MASK),
             space = SHA512_BLOCK_SIZE - pos;
    const unsigned char *sp = data;

    if((ctx->count[0] += len) < len)
        ++(ctx->count[1]);

    while(len >= space)     /* tranfer whole blocks while possible  */
    {
        memcpy(((unsigned char*)ctx->wbuf) + pos, sp, space);
        sp += space; len -= space; space = SHA512_BLOCK_SIZE; pos = 0;
        bsw_64(ctx->wbuf, SHA512_BLOCK_SIZE >> 3);
        sha512_compile(ctx);
    }

    memcpy(((unsigned char*)ctx->wbuf) + pos, sp, len);
}

/* SHA384/512 Final padding and digest calculation  */

static void sha_end2(unsigned char hval[], sha512_ctx ctx[1], const unsigned int hlen)
{   uint_32t    i = (uint_32t)(ctx->count[0] & SHA512_MASK);

    /* put bytes in the buffer in an order in which references to   */
    /* 32-bit words will put bytes with lower addresses into the    */
    /* top of 32 bit words on BOTH big and little endian machines   */
    bsw_64(ctx->wbuf, (i + 7) >> 3);

    /* we now need to mask valid bytes and add the padding which is */
    /* a single 1 bit and as many zero bits as necessary. Note that */
    /* we can always add the first padding byte here because the    */
    /* buffer always has at least one empty slot                    */
    ctx->wbuf[i >> 3] &= li_64(ffffffffffffff00) << 8 * (~i & 7);
    ctx->wbuf[i >> 3] |= li_64(0000000000000080) << 8 * (~i & 7);

    /* we need 17 or more empty byte positions, one for the padding */
    /* byte (above) and sixteen for the length count.  If there is  */
    /* not enough space pad and empty the buffer                    */
    if(i > SHA512_BLOCK_SIZE - 17)
    {
        if(i < 120) ctx->wbuf[15] = 0;
        sha512_compile(ctx);
        i = 0;
    }
    else
        i = (i >> 3) + 1;

    while(i < 14)
        ctx->wbuf[i++] = 0;

    /* the following 64-bit length fields are assembled in the      */
    /* wrong byte order on little endian machines but this is       */
    /* corrected later since they are only ever used as 64-bit      */
    /* word values.                                                 */
    ctx->wbuf[14] = (ctx->count[1] << 3) | (ctx->count[0] >> 61);
    ctx->wbuf[15] = ctx->count[0] << 3;
    sha512_compile(ctx);

    /* extract the hash value as bytes in case the hash buffer is   */
    /* misaligned for 32-bit words                                  */
    for(i = 0; i < hlen; ++i)
        hval[i] = (unsigned char)(ctx->hash[i >> 3] >> (8 * (~i & 7)));
}

#endif

#if defined(SHA_384)

/* SHA384 initialisation data   */

const uint_64t  i384[80] =
{
    li_64(cbbb9d5dc1059ed8), li_64(629a292a367cd507),
    li_64(9159015a3070dd17), li_64(152fecd8f70e5939),
    li_64(67332667ffc00b31), li_64(8eb44a8768581511),
    li_64(db0c2e0d64f98fa7), li_64(47b5481dbefa4fa4)
};

VOID_RETURN sha384_begin(sha384_ctx ctx[1])
{
    ctx->count[0] = ctx->count[1] = 0;
    memcpy(ctx->hash, i384, 8 * sizeof(uint_64t));
}

VOID_RETURN sha384_end(unsigned char hval[], sha384_ctx ctx[1])
{
    sha_end2(hval, ctx, SHA384_DIGEST_SIZE);
}

VOID_RETURN sha384(unsigned char hval[], const unsigned char data[], unsigned long len)
{   sha384_ctx  cx[1];

    sha384_begin(cx);
    sha384_hash(data, len, cx);
    sha_end2(hval, cx, SHA384_DIGEST_SIZE);
}

#endif

#if defined(SHA_512)

/* SHA512 initialisation data   */

const uint_64t  i512[80] =
{
    li_64(6a09e667f3bcc908), li_64(bb67ae8584caa73b),
    li_64(3c6ef372fe94f82b), li_64(a54ff53a5f1d36f1),
    li_64(510e527fade682d1), li_64(9b05688c2b3e6c1f),
    li_64(1f83d9abfb41bd6b), li_64(5be0cd19137e2179)
};

VOID_RETURN sha512_begin(sha512_ctx ctx[1])
{
    ctx->count[0] = ctx->count[1] = 0;
    memcpy(ctx->hash, i512, 8 * sizeof(uint_64t));
}

VOID_RETURN sha512_end(unsigned char hval[], sha512_ctx ctx[1])
{
    sha_end2(hval, ctx, SHA512_DIGEST_SIZE);
}

VOID_RETURN sha512(unsigned char hval[], const unsigned char data[], unsigned long len)
{   sha512_ctx  cx[1];

    sha512_begin(cx);
    sha512_hash(data, len, cx);
    sha_end2(hval, cx, SHA512_DIGEST_SIZE);
}

#endif

#if defined(SHA_2)

#define CTX_224(x)  ((x)->uu->ctx256)
#define CTX_256(x)  ((x)->uu->ctx256)
#define CTX_384(x)  ((x)->uu->ctx512)
#define CTX_512(x)  ((x)->uu->ctx512)

/* SHA2 initialisation */

INT_RETURN sha2_begin(unsigned long len, sha2_ctx ctx[1])
{
    switch(len)
    {
#if defined(SHA_224)
        case 224:
        case  28:   CTX_256(ctx)->count[0] = CTX_256(ctx)->count[1] = 0;
                    memcpy(CTX_256(ctx)->hash, i224, 32);
                    ctx->sha2_len = 28; return EXIT_SUCCESS;
#endif
#if defined(SHA_256)
        case 256:
        case  32:   CTX_256(ctx)->count[0] = CTX_256(ctx)->count[1] = 0;
                    memcpy(CTX_256(ctx)->hash, i256, 32);
                    ctx->sha2_len = 32; return EXIT_SUCCESS;
#endif
#if defined(SHA_384)
        case 384:
        case  48:   CTX_384(ctx)->count[0] = CTX_384(ctx)->count[1] = 0;
                    memcpy(CTX_384(ctx)->hash, i384, 64);
                    ctx->sha2_len = 48; return EXIT_SUCCESS;
#endif
#if defined(SHA_512)
        case 512:
        case  64:   CTX_512(ctx)->count[0] = CTX_512(ctx)->count[1] = 0;
                    memcpy(CTX_512(ctx)->hash, i512, 64);
                    ctx->sha2_len = 64; return EXIT_SUCCESS;
#endif
        default:    return EXIT_FAILURE;
    }
}

VOID_RETURN sha2_hash(const unsigned char data[], unsigned long len, sha2_ctx ctx[1])
{
    switch(ctx->sha2_len)
    {
#if defined(SHA_224)
        case 28: sha224_hash(data, len, CTX_224(ctx)); return;
#endif
#if defined(SHA_256)
        case 32: sha256_hash(data, len, CTX_256(ctx)); return;
#endif
#if defined(SHA_384)
        case 48: sha384_hash(data, len, CTX_384(ctx)); return;
#endif
#if defined(SHA_512)
        case 64: sha512_hash(data, len, CTX_512(ctx)); return;
#endif
    }
}

VOID_RETURN sha2_end(unsigned char hval[], sha2_ctx ctx[1])
{
    switch(ctx->sha2_len)
    {
#if defined(SHA_224)
        case 28: sha_end1(hval, CTX_224(ctx), SHA224_DIGEST_SIZE); return;
#endif
#if defined(SHA_256)
        case 32: sha_end1(hval, CTX_256(ctx), SHA256_DIGEST_SIZE); return;
#endif
#if defined(SHA_384)
        case 48: sha_end2(hval, CTX_384(ctx), SHA384_DIGEST_SIZE); return;
#endif
#if defined(SHA_512)
        case 64: sha_end2(hval, CTX_512(ctx), SHA512_DIGEST_SIZE); return;
#endif
    }
}

INT_RETURN sha2(unsigned char hval[], unsigned long size,
                                const unsigned char data[], unsigned long len)
{   sha2_ctx    cx[1];

    if(sha2_begin(size, cx) == EXIT_SUCCESS)
    {
        sha2_hash(data, len, cx); sha2_end(hval, cx); return EXIT_SUCCESS;
    }
    else
        return EXIT_FAILURE;
}

#endif

#if defined(__cplusplus)
}
#endif