/*
 *	sha512.c
 *	Release $Name: MATRIXSSL-3-6-1-OPEN $
 *
 *	SHA256 hash implementation
 */
/*
 *	Copyright (c) 2013-2014 INSIDE Secure Corporation
 *	Copyright (c) PeerSec Networks, 2002-2011
 *	All Rights Reserved
 *
 *	The latest version of this code is available at http://www.matrixssl.org
 *
 *	This software is open source; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License as published by
 *	the Free Software Foundation; either version 2 of the License, or
 *	(at your option) any later version.
 *
 *	This General Public License does NOT permit incorporating this software 
 *	into proprietary programs.  If you are unable to comply with the GPL, a 
 *	commercial license for this software may be purchased from INSIDE at
 *	http://www.insidesecure.com/eng/Company/Locations
 *	
 *	This program is distributed in WITHOUT ANY WARRANTY; without even the 
 *	implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 
 *	See the GNU General Public License for more details.
 *	
 *	You should have received a copy of the GNU General Public License
 *	along with this program; if not, write to the Free Software
 *	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *	http://www.gnu.org/copyleft/gpl.html
 */
/******************************************************************************/

#include "../cryptoApi.h"

#if defined(USE_SHA512) && defined(HAVE_NATIVE_INT64)

/* the K array */
static const uint64 K[80] = {
CONST64(0x428a2f98d728ae22), CONST64(0x7137449123ef65cd), 
CONST64(0xb5c0fbcfec4d3b2f), CONST64(0xe9b5dba58189dbbc),
CONST64(0x3956c25bf348b538), CONST64(0x59f111f1b605d019), 
CONST64(0x923f82a4af194f9b), CONST64(0xab1c5ed5da6d8118),
CONST64(0xd807aa98a3030242), CONST64(0x12835b0145706fbe), 
CONST64(0x243185be4ee4b28c), CONST64(0x550c7dc3d5ffb4e2),
CONST64(0x72be5d74f27b896f), CONST64(0x80deb1fe3b1696b1), 
CONST64(0x9bdc06a725c71235), CONST64(0xc19bf174cf692694),
CONST64(0xe49b69c19ef14ad2), CONST64(0xefbe4786384f25e3), 
CONST64(0x0fc19dc68b8cd5b5), CONST64(0x240ca1cc77ac9c65),
CONST64(0x2de92c6f592b0275), CONST64(0x4a7484aa6ea6e483), 
CONST64(0x5cb0a9dcbd41fbd4), CONST64(0x76f988da831153b5),
CONST64(0x983e5152ee66dfab), CONST64(0xa831c66d2db43210), 
CONST64(0xb00327c898fb213f), CONST64(0xbf597fc7beef0ee4),
CONST64(0xc6e00bf33da88fc2), CONST64(0xd5a79147930aa725), 
CONST64(0x06ca6351e003826f), CONST64(0x142929670a0e6e70),
CONST64(0x27b70a8546d22ffc), CONST64(0x2e1b21385c26c926), 
CONST64(0x4d2c6dfc5ac42aed), CONST64(0x53380d139d95b3df),
CONST64(0x650a73548baf63de), CONST64(0x766a0abb3c77b2a8), 
CONST64(0x81c2c92e47edaee6), CONST64(0x92722c851482353b),
CONST64(0xa2bfe8a14cf10364), CONST64(0xa81a664bbc423001),
CONST64(0xc24b8b70d0f89791), CONST64(0xc76c51a30654be30),
CONST64(0xd192e819d6ef5218), CONST64(0xd69906245565a910), 
CONST64(0xf40e35855771202a), CONST64(0x106aa07032bbd1b8),
CONST64(0x19a4c116b8d2d0c8), CONST64(0x1e376c085141ab53), 
CONST64(0x2748774cdf8eeb99), CONST64(0x34b0bcb5e19b48a8),
CONST64(0x391c0cb3c5c95a63), CONST64(0x4ed8aa4ae3418acb), 
CONST64(0x5b9cca4f7763e373), CONST64(0x682e6ff3d6b2b8a3),
CONST64(0x748f82ee5defb2fc), CONST64(0x78a5636f43172f60), 
CONST64(0x84c87814a1f0ab72), CONST64(0x8cc702081a6439ec),
CONST64(0x90befffa23631e28), CONST64(0xa4506cebde82bde9), 
CONST64(0xbef9a3f7b2c67915), CONST64(0xc67178f2e372532b),
CONST64(0xca273eceea26619c), CONST64(0xd186b8c721c0c207), 
CONST64(0xeada7dd6cde0eb1e), CONST64(0xf57d4f7fee6ed178),
CONST64(0x06f067aa72176fba), CONST64(0x0a637dc5a2c898a6), 
CONST64(0x113f9804bef90dae), CONST64(0x1b710b35131c471b),
CONST64(0x28db77f523047d84), CONST64(0x32caab7b40c72493), 
CONST64(0x3c9ebe0a15c9bebc), CONST64(0x431d67c49c100d4c),
CONST64(0x4cc5d4becb3e42b6), CONST64(0x597f299cfc657e2a), 
CONST64(0x5fcb6fab3ad6faec), CONST64(0x6c44198c4a475817)
};

/* Various logical functions */
#define Ch(x,y,z)       (z ^ (x & (y ^ z)))
#define Maj(x,y,z)      (((x | y) & z) | (x & y)) 
#define S(x, n)         ROR64c(x, n)
#define R(x, n)         (((x)&CONST64(0xFFFFFFFFFFFFFFFF))>>((uint64)n))
#define Sigma0(x)       (S(x, 28) ^ S(x, 34) ^ S(x, 39))
#define Sigma1(x)       (S(x, 14) ^ S(x, 18) ^ S(x, 41))
#define Gamma0(x)       (S(x, 1) ^ S(x, 8) ^ R(x, 7))
#define Gamma1(x)       (S(x, 19) ^ S(x, 61) ^ R(x, 6))

/* compress 1024-bits */
#ifdef USE_BURN_STACK
static void _sha512_compress(psDigestContext_t * md, unsigned char *buf)
#else
void  sha512_compress(psDigestContext_t * md, unsigned char *buf)
#endif
{
	uint64 S[8], W[80], t0, t1;
    int i;

    /* copy state into S */
    for (i = 0; i < 8; i++) {
        S[i] = md->sha512.state[i];
    }

    /* copy the state into 1024-bits into W[0..15] */
    for (i = 0; i < 16; i++) {
		LOAD64H(W[i], buf + (8*i));
    }

    /* fill W[16..79] */
    for (i = 16; i < 80; i++) {
        W[i] = Gamma1(W[i - 2]) + W[i - 7] + Gamma0(W[i - 15]) + W[i - 16];
    }        

    /* Compress */
#ifndef PS_SHA512_IMPROVE_PERF_INCREASE_CODESIZE
    for (i = 0; i < 80; i++) {
        t0 = S[7] + Sigma1(S[4]) + Ch(S[4], S[5], S[6]) + K[i] + W[i];
		t1 = Sigma0(S[0]) + Maj(S[0], S[1], S[2]);
        S[7] = S[6];
        S[6] = S[5];
        S[5] = S[4];
        S[4] = S[3] + t0;
        S[3] = S[2];
        S[2] = S[1];
        S[1] = S[0];
        S[0] = t0 + t1;
    }
#else
#define RND(a,b,c,d,e,f,g,h,i)                    \
     t0 = h + Sigma1(e) + Ch(e, f, g) + K[i] + W[i];   \
     t1 = Sigma0(a) + Maj(a, b, c);                  \
     d += t0;                                        \
     h  = t0 + t1;

     for (i = 0; i < 80; i += 8) {
         RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],i+0);
         RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],i+1);
         RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],i+2);
         RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],i+3);
         RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],i+4);
         RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],i+5);
         RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],i+6);
         RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],i+7);
     }
#endif /* PS_SHA512_IMPROVE_PERF_INCREASE_CODESIZE */

	/* feedback */
	for (i = 0; i < 8; i++) {
        md->sha512.state[i] = md->sha512.state[i] + S[i];
    }
}

/* compress 1024-bits */
#ifdef USE_BURN_STACK
void sha512_compress(psDigestContext_t * md, unsigned char *buf)
{
    _sha512_compress(md, buf);
    psBurnStack(sizeof(uint64) * 90 + sizeof(int));
}
#endif

void psSha512Init(psDigestContext_t * md)
{
	psAssert(md != NULL);
    md->sha512.curlen = 0;
    md->sha512.length = 0;
    md->sha512.state[0] = CONST64(0x6a09e667f3bcc908);
    md->sha512.state[1] = CONST64(0xbb67ae8584caa73b);
    md->sha512.state[2] = CONST64(0x3c6ef372fe94f82b);
    md->sha512.state[3] = CONST64(0xa54ff53a5f1d36f1);
    md->sha512.state[4] = CONST64(0x510e527fade682d1);
    md->sha512.state[5] = CONST64(0x9b05688c2b3e6c1f);
    md->sha512.state[6] = CONST64(0x1f83d9abfb41bd6b);
    md->sha512.state[7] = CONST64(0x5be0cd19137e2179);
}

void psSha512Update(psDigestContext_t *md, const unsigned char *buf, uint32 len)
{
	uint32 n;

	psAssert(md != NULL);
	psAssert(buf != NULL);

	while (len > 0) {
		if (md->sha512.curlen == 0 && len >= 128) {
			sha512_compress(md, (unsigned char *)buf);
			md->sha512.length += 1024;
			buf		+= 128;
			len		-= 128;
		} else {
			n = min(len, (128 - md->sha512.curlen));
			memcpy(md->sha512.buf + md->sha512.curlen, buf, (size_t)n);
			md->sha512.curlen	+= n;
			buf					+= n;
			len					-= n;

			if (md->sha512.curlen == 128) {
				sha512_compress (md, md->sha512.buf);
				md->sha512.length += 1024;		
				md->sha512.curlen	= 0;
			}
		}
	}
	return;
}

int32 psSha512Final(psDigestContext_t * md, unsigned char *out)
{
	int i;

    psAssert(md  != NULL);
    psAssert(out != NULL);

    if (md->sha512.curlen >= sizeof(md->sha512.buf)) {
       return PS_ARG_FAIL;
    }

    /* increase the length of the message */
	md->sha512.length += md->sha512.curlen * CONST64(8);

    /* append the '1' bit */
    md->sha512.buf[md->sha512.curlen++] = (unsigned char)0x80;

    /* if the length is currently above 112 bytes we append zeros
     * then compress.  Then we can fall back to padding zeros and length
     * encoding like normal.
     */
    if (md->sha512.curlen > 112) {
        while (md->sha512.curlen < 128) {
            md->sha512.buf[md->sha512.curlen++] = (unsigned char)0;
        }
        sha512_compress(md, md->sha512.buf);
        md->sha512.curlen = 0;
    }

    /* pad upto 120 bytes of zeroes 
     * note: that from 112 to 120 is the 64 MSB of the length.  We assume that you won't hash
     * > 2^64 bits of data... :-)
     */
    while (md->sha512.curlen < 120) {
        md->sha512.buf[md->sha512.curlen++] = (unsigned char)0;
    }

    /* store length */
    STORE64H(md->sha512.length, md->sha512.buf+120);
    sha512_compress(md, md->sha512.buf);

    /* copy output */
    for (i = 0; i < 8; i++) {
        STORE64H(md->sha512.state[i], out+(8*i));
    }
#ifdef USE_BURN_STACK
    psBurnStack(sizeof(psDigestContext_t));
#endif
    return SHA512_HASH_SIZE;
}

#endif /* USE_SHA512 */

