/* $OpenBSD: sha256.c,v 1.4 2014/06/12 15:49:30 deraadt Exp $ */
/* ====================================================================
 * Copyright (c) 2004 The OpenSSL Project.  All rights reserved
 * according to the OpenSSL license [found in ../../LICENSE].
 * ====================================================================
 */
#include <openssl/opensslconf.h>
#if !defined(OPENSSL_NO_SHA) && !defined(OPENSSL_NO_SHA256)

#include <stdlib.h>
#include <string.h>
#include <machine/endian.h>

#include <openssl/crypto.h>
#include <openssl/sha.h>
#include <openssl/opensslv.h>

const char SHA256_version[]="SHA-256" OPENSSL_VERSION_PTEXT;

int SHA224_Init(SHA256_CTX *c)
	{
	memset (c,0,sizeof(*c));
	c->h[0]=0xc1059ed8UL;	c->h[1]=0x367cd507UL;
	c->h[2]=0x3070dd17UL;	c->h[3]=0xf70e5939UL;
	c->h[4]=0xffc00b31UL;	c->h[5]=0x68581511UL;
	c->h[6]=0x64f98fa7UL;	c->h[7]=0xbefa4fa4UL;
	c->md_len=SHA224_DIGEST_LENGTH;
	return 1;
	}

int SHA256_Init(SHA256_CTX *c)
	{
	memset (c,0,sizeof(*c));
	c->h[0]=0x6a09e667UL;	c->h[1]=0xbb67ae85UL;
	c->h[2]=0x3c6ef372UL;	c->h[3]=0xa54ff53aUL;
	c->h[4]=0x510e527fUL;	c->h[5]=0x9b05688cUL;
	c->h[6]=0x1f83d9abUL;	c->h[7]=0x5be0cd19UL;
	c->md_len=SHA256_DIGEST_LENGTH;
	return 1;
	}

unsigned char *SHA224(const unsigned char *d, size_t n, unsigned char *md)
	{
	SHA256_CTX c;
	static unsigned char m[SHA224_DIGEST_LENGTH];

	if (md == NULL) md=m;
	SHA224_Init(&c);
	SHA256_Update(&c,d,n);
	SHA256_Final(md,&c);
	OPENSSL_cleanse(&c,sizeof(c));
	return(md);
	}

unsigned char *SHA256(const unsigned char *d, size_t n, unsigned char *md)
	{
	SHA256_CTX c;
	static unsigned char m[SHA256_DIGEST_LENGTH];

	if (md == NULL) md=m;
	SHA256_Init(&c);
	SHA256_Update(&c,d,n);
	SHA256_Final(md,&c);
	OPENSSL_cleanse(&c,sizeof(c));
	return(md);
	}

int SHA224_Update(SHA256_CTX *c, const void *data, size_t len)
{   return SHA256_Update (c,data,len);   }
int SHA224_Final (unsigned char *md, SHA256_CTX *c)
{   return SHA256_Final (md,c);   }

#define	DATA_ORDER_IS_BIG_ENDIAN

#define	HASH_LONG		SHA_LONG
#define	HASH_CTX		SHA256_CTX
#define	HASH_CBLOCK		SHA_CBLOCK
/*
 * Note that FIPS180-2 discusses "Truncation of the Hash Function Output."
 * default: case below covers for it. It's not clear however if it's
 * permitted to truncate to amount of bytes not divisible by 4. I bet not,
 * but if it is, then default: case shall be extended. For reference.
 * Idea behind separate cases for pre-defined lenghts is to let the
 * compiler decide if it's appropriate to unroll small loops.
 */
#define	HASH_MAKE_STRING(c,s)	do {	\
	unsigned long ll;		\
	unsigned int  nn;		\
	switch ((c)->md_len)		\
	{   case SHA224_DIGEST_LENGTH:	\
		for (nn=0;nn<SHA224_DIGEST_LENGTH/4;nn++)	\
		{   ll=(c)->h[nn]; (void)HOST_l2c(ll,(s));   }	\
		break;			\
	    case SHA256_DIGEST_LENGTH:	\
		for (nn=0;nn<SHA256_DIGEST_LENGTH/4;nn++)	\
		{   ll=(c)->h[nn]; (void)HOST_l2c(ll,(s));   }	\
		break;			\
	    default:			\
		if ((c)->md_len > SHA256_DIGEST_LENGTH)	\
		    return 0;				\
		for (nn=0;nn<(c)->md_len/4;nn++)		\
		{   ll=(c)->h[nn]; (void)HOST_l2c(ll,(s));   }	\
		break;			\
	}				\
	} while (0)

#define	HASH_UPDATE		SHA256_Update
#define	HASH_TRANSFORM		SHA256_Transform
#define	HASH_FINAL		SHA256_Final
#define	HASH_BLOCK_DATA_ORDER	sha256_block_data_order
#ifndef SHA256_ASM
static
#endif
void sha256_block_data_order (SHA256_CTX *ctx, const void *in, size_t num);

#include "md32_common.h"

#ifndef SHA256_ASM
static const SHA_LONG 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 };

/*
 * FIPS specification refers to right rotations, while our ROTATE macro
 * is left one. This is why you might notice that rotation coefficients
 * differ from those observed in FIPS document by 32-N...
 */
#define Sigma0(x)	(ROTATE((x),30) ^ ROTATE((x),19) ^ ROTATE((x),10))
#define Sigma1(x)	(ROTATE((x),26) ^ ROTATE((x),21) ^ ROTATE((x),7))
#define sigma0(x)	(ROTATE((x),25) ^ ROTATE((x),14) ^ ((x)>>3))
#define sigma1(x)	(ROTATE((x),15) ^ ROTATE((x),13) ^ ((x)>>10))

#define Ch(x,y,z)	(((x) & (y)) ^ ((~(x)) & (z)))
#define Maj(x,y,z)	(((x) & (y)) ^ ((x) & (z)) ^ ((y) & (z)))

#ifdef OPENSSL_SMALL_FOOTPRINT

static void sha256_block_data_order (SHA256_CTX *ctx, const void *in, size_t num)
	{
	unsigned MD32_REG_T a,b,c,d,e,f,g,h,s0,s1,T1,T2;
	SHA_LONG	X[16],l;
	int i;
	const unsigned char *data=in;

			while (num--) {

	a = ctx->h[0];	b = ctx->h[1];	c = ctx->h[2];	d = ctx->h[3];
	e = ctx->h[4];	f = ctx->h[5];	g = ctx->h[6];	h = ctx->h[7];

	for (i=0;i<16;i++)
		{
		HOST_c2l(data,l); T1 = X[i] = l;
		T1 += h + Sigma1(e) + Ch(e,f,g) + K256[i];
		T2 = Sigma0(a) + Maj(a,b,c);
		h = g;	g = f;	f = e;	e = d + T1;
		d = c;	c = b;	b = a;	a = T1 + T2;
		}

	for (;i<64;i++)
		{
		s0 = X[(i+1)&0x0f];	s0 = sigma0(s0);
		s1 = X[(i+14)&0x0f];	s1 = sigma1(s1);

		T1 = X[i&0xf] += s0 + s1 + X[(i+9)&0xf];
		T1 += h + Sigma1(e) + Ch(e,f,g) + K256[i];
		T2 = Sigma0(a) + Maj(a,b,c);
		h = g;	g = f;	f = e;	e = d + T1;
		d = c;	c = b;	b = a;	a = T1 + T2;
		}

	ctx->h[0] += a;	ctx->h[1] += b;	ctx->h[2] += c;	ctx->h[3] += d;
	ctx->h[4] += e;	ctx->h[5] += f;	ctx->h[6] += g;	ctx->h[7] += h;

			}
}

#else

#define	ROUND_00_15(i,a,b,c,d,e,f,g,h)		do {	\
	T1 += h + Sigma1(e) + Ch(e,f,g) + K256[i];	\
	h = Sigma0(a) + Maj(a,b,c);			\
	d += T1;	h += T1;		} while (0)

#define	ROUND_16_63(i,a,b,c,d,e,f,g,h,X)	do {	\
	s0 = X[(i+1)&0x0f];	s0 = sigma0(s0);	\
	s1 = X[(i+14)&0x0f];	s1 = sigma1(s1);	\
	T1 = X[(i)&0x0f] += s0 + s1 + X[(i+9)&0x0f];	\
	ROUND_00_15(i,a,b,c,d,e,f,g,h);		} while (0)

static void sha256_block_data_order (SHA256_CTX *ctx, const void *in, size_t num)
	{
	unsigned MD32_REG_T a,b,c,d,e,f,g,h,s0,s1,T1;
	SHA_LONG	X[16];
	int i;
	const unsigned char *data=in;

			while (num--) {

	a = ctx->h[0];	b = ctx->h[1];	c = ctx->h[2];	d = ctx->h[3];
	e = ctx->h[4];	f = ctx->h[5];	g = ctx->h[6];	h = ctx->h[7];

	if (_BYTE_ORDER != _LITTLE_ENDIAN &&
	    sizeof(SHA_LONG)==4 && ((size_t)in%4)==0)
		{
		const SHA_LONG *W=(const SHA_LONG *)data;

		T1 = X[0] = W[0];	ROUND_00_15(0,a,b,c,d,e,f,g,h);
		T1 = X[1] = W[1];	ROUND_00_15(1,h,a,b,c,d,e,f,g);
		T1 = X[2] = W[2];	ROUND_00_15(2,g,h,a,b,c,d,e,f);
		T1 = X[3] = W[3];	ROUND_00_15(3,f,g,h,a,b,c,d,e);
		T1 = X[4] = W[4];	ROUND_00_15(4,e,f,g,h,a,b,c,d);
		T1 = X[5] = W[5];	ROUND_00_15(5,d,e,f,g,h,a,b,c);
		T1 = X[6] = W[6];	ROUND_00_15(6,c,d,e,f,g,h,a,b);
		T1 = X[7] = W[7];	ROUND_00_15(7,b,c,d,e,f,g,h,a);
		T1 = X[8] = W[8];	ROUND_00_15(8,a,b,c,d,e,f,g,h);
		T1 = X[9] = W[9];	ROUND_00_15(9,h,a,b,c,d,e,f,g);
		T1 = X[10] = W[10];	ROUND_00_15(10,g,h,a,b,c,d,e,f);
		T1 = X[11] = W[11];	ROUND_00_15(11,f,g,h,a,b,c,d,e);
		T1 = X[12] = W[12];	ROUND_00_15(12,e,f,g,h,a,b,c,d);
		T1 = X[13] = W[13];	ROUND_00_15(13,d,e,f,g,h,a,b,c);
		T1 = X[14] = W[14];	ROUND_00_15(14,c,d,e,f,g,h,a,b);
		T1 = X[15] = W[15];	ROUND_00_15(15,b,c,d,e,f,g,h,a);

		data += SHA256_CBLOCK;
		}
	else
		{
		SHA_LONG l;

		HOST_c2l(data,l); T1 = X[0] = l;  ROUND_00_15(0,a,b,c,d,e,f,g,h);
		HOST_c2l(data,l); T1 = X[1] = l;  ROUND_00_15(1,h,a,b,c,d,e,f,g);
		HOST_c2l(data,l); T1 = X[2] = l;  ROUND_00_15(2,g,h,a,b,c,d,e,f);
		HOST_c2l(data,l); T1 = X[3] = l;  ROUND_00_15(3,f,g,h,a,b,c,d,e);
		HOST_c2l(data,l); T1 = X[4] = l;  ROUND_00_15(4,e,f,g,h,a,b,c,d);
		HOST_c2l(data,l); T1 = X[5] = l;  ROUND_00_15(5,d,e,f,g,h,a,b,c);
		HOST_c2l(data,l); T1 = X[6] = l;  ROUND_00_15(6,c,d,e,f,g,h,a,b);
		HOST_c2l(data,l); T1 = X[7] = l;  ROUND_00_15(7,b,c,d,e,f,g,h,a);
		HOST_c2l(data,l); T1 = X[8] = l;  ROUND_00_15(8,a,b,c,d,e,f,g,h);
		HOST_c2l(data,l); T1 = X[9] = l;  ROUND_00_15(9,h,a,b,c,d,e,f,g);
		HOST_c2l(data,l); T1 = X[10] = l; ROUND_00_15(10,g,h,a,b,c,d,e,f);
		HOST_c2l(data,l); T1 = X[11] = l; ROUND_00_15(11,f,g,h,a,b,c,d,e);
		HOST_c2l(data,l); T1 = X[12] = l; ROUND_00_15(12,e,f,g,h,a,b,c,d);
		HOST_c2l(data,l); T1 = X[13] = l; ROUND_00_15(13,d,e,f,g,h,a,b,c);
		HOST_c2l(data,l); T1 = X[14] = l; ROUND_00_15(14,c,d,e,f,g,h,a,b);
		HOST_c2l(data,l); T1 = X[15] = l; ROUND_00_15(15,b,c,d,e,f,g,h,a);
		}

	for (i=16;i<64;i+=8)
		{
		ROUND_16_63(i+0,a,b,c,d,e,f,g,h,X);
		ROUND_16_63(i+1,h,a,b,c,d,e,f,g,X);
		ROUND_16_63(i+2,g,h,a,b,c,d,e,f,X);
		ROUND_16_63(i+3,f,g,h,a,b,c,d,e,X);
		ROUND_16_63(i+4,e,f,g,h,a,b,c,d,X);
		ROUND_16_63(i+5,d,e,f,g,h,a,b,c,X);
		ROUND_16_63(i+6,c,d,e,f,g,h,a,b,X);
		ROUND_16_63(i+7,b,c,d,e,f,g,h,a,X);
		}

	ctx->h[0] += a;	ctx->h[1] += b;	ctx->h[2] += c;	ctx->h[3] += d;
	ctx->h[4] += e;	ctx->h[5] += f;	ctx->h[6] += g;	ctx->h[7] += h;

			}
	}

#endif
#endif /* SHA256_ASM */

#endif /* OPENSSL_NO_SHA256 */