kern/lib/random/sha2.c - akaros - Git at Google

 /*	$OpenBSD: sha2.c,v 1.6 2004/05/03 02:57:36 millert Exp $	*/

 /*
  * FILE:	sha2.c
  * AUTHOR:	Aaron D. Gifford <me@aarongifford.com>
  *
  * Copyright (c) 2000-2001, Aaron D. Gifford
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *	  notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *	  notice, this list of conditions and the following disclaimer in the
  *	  documentation and/or other materials provided with the distribution.
  * 3. Neither the name of the copyright holder nor the names of contributors
  *	  may be used to endorse or promote products derived from this software
  *	  without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTOR(S) ``AS IS'' AND
  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED.	IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTOR(S) BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
  * $From: sha2.c,v 1.1 2001/11/08 00:01:51 adg Exp adg $
  *
  * contrib/pgcrypto/sha2.c
  */

 #include <random/sha2.h>

 /*** SHA-256/512 Various Length Definitions ***********************/
 enum { SHA256ShortBlockLength = (SHA256BlockLength - 8),
        SHA512ShortBlockLength = (SHA512_block_length - 16) };

 /*
  * Macro for incrementally adding the unsigned 64-bit integer n to the
  * unsigned 128-bit integer (represented using a two-element array of
  * 64-bit words):
  */
 #define ADDINC128(w, n)                                                        \
 	{                                                                      \
 		(w)[0] += (uint64_t)(n);                                       \
 		if ((w)[0] < (n)) {                                            \
 			(w)[1]++;                                              \
 		}                                                              \
 	}

 /*** THE SIX LOGICAL FUNCTIONS ****************************************/
 /*
  * Bit shifting and rotation (used by the six SHA-XYZ logical functions:
  *
  *   NOTE:  The naming of R and S appears backwards here (R is a SHIFT and
  *   S is a ROTATION) because the SHA-256/384/512 description document
  *   (see http://csrc.nist.gov/cryptval/shs/sha256-384-512.pdf) uses this
  *   same "backwards" definition.
  */
 /* Shift-right (used in SHA-256, SHA-384, and SHA-512): */
 #define R(b, x) ((x) >> (b))
 /* 32-bit Rotate-right (used in SHA-256): */
 #define S32(b, x) (((x) >> (b)) | ((x) << (32 - (b))))
 /* 64-bit Rotate-right (used in SHA-384 and SHA-512): */
 #define S64(b, x) (((x) >> (b)) | ((x) << (64 - (b))))

 /* Two of six logical functions used in SHA-256, SHA-384, and SHA-512: */
 #define Ch(x, y, z) (((x) & (y)) ^ ((~(x)) & (z)))
 #define Maj(x, y, z) (((x) & (y)) ^ ((x) & (z)) ^ ((y) & (z)))

 /* Four of six logical functions used in SHA-256: */
 #define Sigma0_256(x) (S32(2, (x)) ^ S32(13, (x)) ^ S32(22, (x)))
 #define Sigma1_256(x) (S32(6, (x)) ^ S32(11, (x)) ^ S32(25, (x)))
 #define sigma0_256(x) (S32(7, (x)) ^ S32(18, (x)) ^ R(3, (x)))
 #define sigma1_256(x) (S32(17, (x)) ^ S32(19, (x)) ^ R(10, (x)))

 /* Four of six logical functions used in SHA-384 and SHA-512: */
 #define Sigma0_512(x) (S64(28, (x)) ^ S64(34, (x)) ^ S64(39, (x)))
 #define Sigma1_512(x) (S64(14, (x)) ^ S64(18, (x)) ^ S64(41, (x)))
 #define sigma0_512(x) (S64(1, (x)) ^ S64(8, (x)) ^ R(7, (x)))
 #define sigma1_512(x) (S64(19, (x)) ^ S64(61, (x)) ^ R(6, (x)))

 /*** INTERNAL FUNCTION PROTOTYPES *************************************/
 /* NOTE: These should not be accessed directly from outside this
  * library -- they are intended for private internal visibility/use
  * only.
  */
 static void SHA512_Last(SHA512Ctx *);
 static void SHA256_Transform(SHA256Ctx *, const uint32_t *);
 static void SHA512_Transform(SHA512Ctx *, const uint64_t *);

 /*** SHA-XYZ INITIAL HASH VALUES AND CONSTANTS ************************/
 /* Hash constant words K for SHA-256: */
 const uint32_t 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};

 /* Initial hash value H for SHA-224: */
 const uint32_t sha224_initial_hash_value[8] = {
     0xc1059ed8UL, 0x367cd507UL, 0x3070dd17UL, 0xf70e5939UL,
     0xffc00b31UL, 0x68581511UL, 0x64f98fa7UL, 0xbefa4fa4UL};

 /* Initial hash value H for SHA-256: */
 static const uint32_t sha256_initial_hash_value[8] = {
     0x6a09e667UL, 0xbb67ae85UL, 0x3c6ef372UL, 0xa54ff53aUL,
     0x510e527fUL, 0x9b05688cUL, 0x1f83d9abUL, 0x5be0cd19UL};

 /* Hash constant words K for SHA-384 and SHA-512: */
 static const uint64_t K512[80] = {
     0x428a2f98d728ae22ULL, 0x7137449123ef65cdULL, 0xb5c0fbcfec4d3b2fULL,
     0xe9b5dba58189dbbcULL, 0x3956c25bf348b538ULL, 0x59f111f1b605d019ULL,
     0x923f82a4af194f9bULL, 0xab1c5ed5da6d8118ULL, 0xd807aa98a3030242ULL,
     0x12835b0145706fbeULL, 0x243185be4ee4b28cULL, 0x550c7dc3d5ffb4e2ULL,
     0x72be5d74f27b896fULL, 0x80deb1fe3b1696b1ULL, 0x9bdc06a725c71235ULL,
     0xc19bf174cf692694ULL, 0xe49b69c19ef14ad2ULL, 0xefbe4786384f25e3ULL,
     0x0fc19dc68b8cd5b5ULL, 0x240ca1cc77ac9c65ULL, 0x2de92c6f592b0275ULL,
     0x4a7484aa6ea6e483ULL, 0x5cb0a9dcbd41fbd4ULL, 0x76f988da831153b5ULL,
     0x983e5152ee66dfabULL, 0xa831c66d2db43210ULL, 0xb00327c898fb213fULL,
     0xbf597fc7beef0ee4ULL, 0xc6e00bf33da88fc2ULL, 0xd5a79147930aa725ULL,
     0x06ca6351e003826fULL, 0x142929670a0e6e70ULL, 0x27b70a8546d22ffcULL,
     0x2e1b21385c26c926ULL, 0x4d2c6dfc5ac42aedULL, 0x53380d139d95b3dfULL,
     0x650a73548baf63deULL, 0x766a0abb3c77b2a8ULL, 0x81c2c92e47edaee6ULL,
     0x92722c851482353bULL, 0xa2bfe8a14cf10364ULL, 0xa81a664bbc423001ULL,
     0xc24b8b70d0f89791ULL, 0xc76c51a30654be30ULL, 0xd192e819d6ef5218ULL,
     0xd69906245565a910ULL, 0xf40e35855771202aULL, 0x106aa07032bbd1b8ULL,
     0x19a4c116b8d2d0c8ULL, 0x1e376c085141ab53ULL, 0x2748774cdf8eeb99ULL,
     0x34b0bcb5e19b48a8ULL, 0x391c0cb3c5c95a63ULL, 0x4ed8aa4ae3418acbULL,
     0x5b9cca4f7763e373ULL, 0x682e6ff3d6b2b8a3ULL, 0x748f82ee5defb2fcULL,
     0x78a5636f43172f60ULL, 0x84c87814a1f0ab72ULL, 0x8cc702081a6439ecULL,
     0x90befffa23631e28ULL, 0xa4506cebde82bde9ULL, 0xbef9a3f7b2c67915ULL,
     0xc67178f2e372532bULL, 0xca273eceea26619cULL, 0xd186b8c721c0c207ULL,
     0xeada7dd6cde0eb1eULL, 0xf57d4f7fee6ed178ULL, 0x06f067aa72176fbaULL,
     0x0a637dc5a2c898a6ULL, 0x113f9804bef90daeULL, 0x1b710b35131c471bULL,
     0x28db77f523047d84ULL, 0x32caab7b40c72493ULL, 0x3c9ebe0a15c9bebcULL,
     0x431d67c49c100d4cULL, 0x4cc5d4becb3e42b6ULL, 0x597f299cfc657e2aULL,
     0x5fcb6fab3ad6faecULL, 0x6c44198c4a475817ULL};

 /* Initial hash value H for SHA-384 */
 static const uint64_t sha384_initial_hash_value[8] = {
     0xcbbb9d5dc1059ed8ULL, 0x629a292a367cd507ULL, 0x9159015a3070dd17ULL,
     0x152fecd8f70e5939ULL, 0x67332667ffc00b31ULL, 0x8eb44a8768581511ULL,
     0xdb0c2e0d64f98fa7ULL, 0x47b5481dbefa4fa4ULL};

 /* Initial hash value H for SHA-512 */
 static const uint64_t sha512_initial_hash_value[8] = {
     0x6a09e667f3bcc908ULL, 0xbb67ae8584caa73bULL, 0x3c6ef372fe94f82bULL,
     0xa54ff53a5f1d36f1ULL, 0x510e527fade682d1ULL, 0x9b05688c2b3e6c1fULL,
     0x1f83d9abfb41bd6bULL, 0x5be0cd19137e2179ULL};

 /*** SHA-256: *********************************************************/
 void SHA256_Init(SHA256Ctx *context)
 {
 	if (context == NULL)
 		return;
 	memmove(context->state, sha256_initial_hash_value, SHA256DigestLength);
 	memset(context->buffer, 0, SHA256BlockLength);
 	context->bitcount = 0;
 }
 static void SHA256_Transform(SHA256Ctx *context, const uint32_t *data)
 {
 	uint32_t a, b, c, d, e, f, g, h, s0, s1;
 	uint32_t T1, T2, *W256;
 	int j;

 	W256 = (uint32_t *)context->buffer;

 	/* Initialize registers with the prev. intermediate value */
 	a = context->state[0];
 	b = context->state[1];
 	c = context->state[2];
 	d = context->state[3];
 	e = context->state[4];
 	f = context->state[5];
 	g = context->state[6];
 	h = context->state[7];

 	j = 0;
 	do {
 		W256[j] = (uint32_t)data[3] | ((uint32_t)data[2] << 8) |
 		          ((uint32_t)data[1] << 16) | ((uint32_t)data[0] << 24);
 		data += 4;
 		/* Apply the SHA-256 compression function to update a..h */
 		T1 = h + Sigma1_256(e) + Ch(e, f, g) + K256[j] + W256[j];
 		T2 = Sigma0_256(a) + Maj(a, b, c);
 		h = g;
 		g = f;
 		f = e;
 		e = d + T1;
 		d = c;
 		c = b;
 		b = a;
 		a = T1 + T2;

 		j++;
 	} while (j < 16);

 	do {
 		/* Part of the message block expansion: */
 		s0 = W256[(j + 1) & 0x0f];
 		s0 = sigma0_256(s0);
 		s1 = W256[(j + 14) & 0x0f];
 		s1 = sigma1_256(s1);

 		/* Apply the SHA-256 compression function to update a..h */
 		T1 = h + Sigma1_256(e) + Ch(e, f, g) + K256[j] +
 		     (W256[j & 0x0f] += s1 + W256[(j + 9) & 0x0f] + s0);
 		T2 = Sigma0_256(a) + Maj(a, b, c);
 		h = g;
 		g = f;
 		f = e;
 		e = d + T1;
 		d = c;
 		c = b;
 		b = a;
 		a = T1 + T2;

 		j++;
 	} while (j < 64);

 	/* Compute the current intermediate hash value */
 	context->state[0] += a;
 	context->state[1] += b;
 	context->state[2] += c;
 	context->state[3] += d;
 	context->state[4] += e;
 	context->state[5] += f;
 	context->state[6] += g;
 	context->state[7] += h;

 	/* Clean up */
 	a = b = c = d = e = f = g = h = T1 = T2 = 0;
 }

 void SHA256_Update(SHA256Ctx *context, const uint8_t *data, size_t len)
 {
 	size_t freespace, usedspace;

 	/* Calling with no data is valid (we do nothing) */
 	if (len == 0)
 		return;

 	usedspace = (context->bitcount >> 3) % SHA256BlockLength;
 	if (usedspace > 0) {
 		/* Calculate how much free space is available in the buffer */
 		freespace = SHA256BlockLength - usedspace;

 		if (len >= freespace) {
 			/* Fill the buffer completely and process it */
 			memmove(&context->buffer[usedspace], data, freespace);
 			context->bitcount += freespace << 3;
 			len -= freespace;
 			data += freespace;
 			SHA256_Transform(context, (uint32_t *)context->buffer);
 		} else {
 			/* The buffer is not yet full */
 			memmove(&context->buffer[usedspace], data, len);
 			context->bitcount += len << 3;
 			/* Clean up: */
 			usedspace = freespace = 0;
 			return;
 		}
 	}
 	while (len >= SHA256BlockLength) {
 		/* Process as many complete blocks as we can */
 		SHA256_Transform(context, (const uint32_t *)data);
 		context->bitcount += SHA256BlockLength << 3;
 		len -= SHA256BlockLength;
 		data += SHA256BlockLength;
 	}
 	if (len > 0) {
 		/* There's left-overs, so save 'em */
 		memmove(context->buffer, data, len);
 		context->bitcount += len << 3;
 	}
 	/* Clean up: */
 	usedspace = freespace = 0;
 }

 static void SHA256_Last(SHA256Ctx *context)
 {
 	unsigned int usedspace;

 	usedspace = (context->bitcount >> 3) % SHA256BlockLength;

 	if (usedspace > 0) {
 		/* Begin padding with a 1 bit: */
 		context->buffer[usedspace++] = 0x80;

 		if (usedspace <= SHA256ShortBlockLength) {
 			/* Set-up for the last transform: */
 			memset(&context->buffer[usedspace], 0,
 			       SHA256ShortBlockLength - usedspace);
 		} else {
 			if (usedspace < SHA256BlockLength) {
 				memset(&context->buffer[usedspace], 0,
 				       SHA256BlockLength - usedspace);
 			}
 			/* Do second-to-last transform: */
 			SHA256_Transform(context, (uint32_t *)context->buffer);

 			/* And set-up for the last transform: */
 			memset(context->buffer, 0, SHA256ShortBlockLength);
 		}
 	} else {
 		/* Set-up for the last transform: */
 		memset(context->buffer, 0, SHA256ShortBlockLength);

 		/* Begin padding with a 1 bit: */
 		*context->buffer = 0x80;
 	}
 	/* Set the bit count: */
 	*(uint64_t *)&context->buffer[SHA256ShortBlockLength] =
 	    context->bitcount;

 	/* Final transform: */
 	SHA256_Transform(context, (uint32_t *)context->buffer);
 }

 void SHA256_Final(uint8_t digest[], SHA256Ctx *context)
 {
 	/* If no digest buffer is passed, we don't bother doing this: */
 	if (digest != NULL) {
 		SHA256_Last(context);

 		memmove(digest, context->state, SHA256DigestLength);
 	}

 	/* Clean up state data: */
 	memset(context, 0, sizeof(*context));
 }

 /*** SHA-512: *********************************************************/
 void SHA512_Init(SHA512Ctx *context)
 {
 	if (context == NULL)
 		return;
 	memmove(context->state, sha512_initial_hash_value, SHA512DigestLength);
 	memset(context->buffer, 0, SHA512_block_length);
 	context->bitcount[0] = context->bitcount[1] = 0;
 }

 static void SHA512_Transform(SHA512Ctx *context, const uint64_t *data)
 {
 	uint64_t a, b, c, d, e, f, g, h, s0, s1;
 	uint64_t T1, T2, *W512 = (uint64_t *)context->buffer;
 	int j;

 	/* Initialize registers with the prev. intermediate value */
 	a = context->state[0];
 	b = context->state[1];
 	c = context->state[2];
 	d = context->state[3];
 	e = context->state[4];
 	f = context->state[5];
 	g = context->state[6];
 	h = context->state[7];

 	j = 0;
 	do {
 		W512[j] =
 		    (uint64_t)data[7] | ((uint64_t)data[6] << 8) |
 		    ((uint64_t)data[5] << 16) | ((uint64_t)data[4] << 24) |
 		    ((uint64_t)data[3] << 32) | ((uint64_t)data[2] << 40) |
 		    ((uint64_t)data[1] << 48) | ((uint64_t)data[0] << 56);
 		data += 8;
 		/* Apply the SHA-512 compression function to update a..h */
 		T1 = h + Sigma1_512(e) + Ch(e, f, g) + K512[j] + W512[j];
 		T2 = Sigma0_512(a) + Maj(a, b, c);
 		h = g;
 		g = f;
 		f = e;
 		e = d + T1;
 		d = c;
 		c = b;
 		b = a;
 		a = T1 + T2;

 		j++;
 	} while (j < 16);

 	do {
 		/* Part of the message block expansion: */
 		s0 = W512[(j + 1) & 0x0f];
 		s0 = sigma0_512(s0);
 		s1 = W512[(j + 14) & 0x0f];
 		s1 = sigma1_512(s1);

 		/* Apply the SHA-512 compression function to update a..h */
 		T1 = h + Sigma1_512(e) + Ch(e, f, g) + K512[j] +
 		     (W512[j & 0x0f] += s1 + W512[(j + 9) & 0x0f] + s0);
 		T2 = Sigma0_512(a) + Maj(a, b, c);
 		h = g;
 		g = f;
 		f = e;
 		e = d + T1;
 		d = c;
 		c = b;
 		b = a;
 		a = T1 + T2;

 		j++;
 	} while (j < 80);

 	/* Compute the current intermediate hash value */
 	context->state[0] += a;
 	context->state[1] += b;
 	context->state[2] += c;
 	context->state[3] += d;
 	context->state[4] += e;
 	context->state[5] += f;
 	context->state[6] += g;
 	context->state[7] += h;

 	/* Clean up */
 	a = b = c = d = e = f = g = h = T1 = T2 = 0;
 }

 void SHA512_Update(SHA512Ctx *context, const uint8_t *data, size_t len)
 {
 	size_t freespace, usedspace;

 	/* Calling with no data is valid (we do nothing) */
 	if (len == 0)
 		return;

 	usedspace = (context->bitcount[0] >> 3) % SHA512_block_length;
 	if (usedspace > 0) {
 		/* Calculate how much free space is available in the buffer */
 		freespace = SHA512_block_length - usedspace;

 		if (len >= freespace) {
 			/* Fill the buffer completely and process it */
 			memmove(&context->buffer[usedspace], data, freespace);
 			ADDINC128(context->bitcount, freespace << 3);
 			len -= freespace;
 			data += freespace;
 			SHA512_Transform(context, (uint64_t *)context->buffer);
 		} else {
 			/* The buffer is not yet full */
 			memmove(&context->buffer[usedspace], data, len);
 			ADDINC128(context->bitcount, len << 3);
 			/* Clean up: */
 			usedspace = freespace = 0;
 			return;
 		}
 	}
 	while (len >= SHA512_block_length) {
 		/* Process as many complete blocks as we can */
 		SHA512_Transform(context, (const uint64_t *)data);
 		ADDINC128(context->bitcount, SHA512_block_length << 3);
 		len -= SHA512_block_length;
 		data += SHA512_block_length;
 	}
 	if (len > 0) {
 		/* There's left-overs, so save 'em */
 		memmove(context->buffer, data, len);
 		ADDINC128(context->bitcount, len << 3);
 	}
 	/* Clean up: */
 	usedspace = freespace = 0;
 }

 static void SHA512_Last(SHA512Ctx *context)
 {
 	unsigned int usedspace;

 	usedspace = (context->bitcount[0] >> 3) % SHA512_block_length;

 	if (usedspace > 0) {
 		/* Begin padding with a 1 bit: */
 		context->buffer[usedspace++] = 0x80;

 		if (usedspace <= SHA512ShortBlockLength) {
 			/* Set-up for the last transform: */
 			memset(&context->buffer[usedspace], 0,
 			       SHA512ShortBlockLength - usedspace);
 		} else {
 			if (usedspace < SHA512_block_length) {
 				memset(&context->buffer[usedspace], 0,
 				       SHA512_block_length - usedspace);
 			}
 			/* Do second-to-last transform: */
 			SHA512_Transform(context, (uint64_t *)context->buffer);

 			/* And set-up for the last transform: */
 			memset(context->buffer, 0, SHA512_block_length - 2);
 		}
 	} else {
 		/* Prepare for final transform: */
 		memset(context->buffer, 0, SHA512ShortBlockLength);

 		/* Begin padding with a 1 bit: */
 		*context->buffer = 0x80;
 	}
 	/* Store the length of input data (in bits): */
 	*(uint64_t *)&context->buffer[SHA512ShortBlockLength] =
 	    context->bitcount[1];
 	*(uint64_t *)&context->buffer[SHA512ShortBlockLength + 8] =
 	    context->bitcount[0];

 	/* Final transform: */
 	SHA512_Transform(context, (uint64_t *)context->buffer);
 }

 void SHA512_Final(uint8_t digest[], SHA512Ctx *context)
 {
 	/* If no digest buffer is passed, we don't bother doing this: */
 	if (digest != NULL) {
 		SHA512_Last(context);

 		/* Save the hash data for output: */
 		memmove(digest, context->state, SHA512DigestLength);
 	}

 	/* Zero out state data */
 	memset(context, 0, sizeof(*context));
 }

 /*** SHA-384: *********************************************************/
 void SHA384_Init(SHA384Ctx *context)
 {
 	if (context == NULL)
 		return;
 	memmove(context->state, sha384_initial_hash_value, SHA512DigestLength);
 	memset(context->buffer, 0, SHA384BlockLength);
 	context->bitcount[0] = context->bitcount[1] = 0;
 }

 void SHA384_Update(SHA384Ctx *context, const uint8_t *data, size_t len)
 {
 	SHA512_Update((SHA512Ctx *)context, data, len);
 }

 void SHA384_Final(uint8_t digest[], SHA384Ctx *context)
 {
 	/* If no digest buffer is passed, we don't bother doing this: */
 	if (digest != NULL) {
 		SHA512_Last((SHA512Ctx *)context);

 		/* Save the hash data for output: */
 		memmove(digest, context->state, SHA384DigestLength);
 	}

 	/* Zero out state data */
 	memset(context, 0, sizeof(*context));
 }

 /*** SHA-224: *********************************************************/
 void SHA224_Init(SHA224Ctx *context)
 {
 	if (context == NULL)
 		return;
 	memmove(context->state, sha224_initial_hash_value, SHA256DigestLength);
 	memset(context->buffer, 0, SHA256BlockLength);
 	context->bitcount = 0;
 }

 void SHA224_Update(SHA224Ctx *context, const uint8_t *data, size_t len)
 {
 	SHA256_Update((SHA256Ctx *)context, data, len);
 }

 void SHA224_Final(uint8_t digest[], SHA224Ctx *context)
 {
 	/* If no digest buffer is passed, we don't bother doing this: */
 	if (digest != NULL) {
 		SHA256_Last(context);

 		memmove(digest, context->state, SHA224DigestLength);
 	}

 	/* Clean up state data: */
 	memset(context, 0, sizeof(*context));
 }
	/* $OpenBSD: sha2.c,v 1.6 2004/05/03 02:57:36 millert Exp $ */

	/*
	* FILE: sha2.c
	* AUTHOR: Aaron D. Gifford <me@aarongifford.com>
	*
	* Copyright (c) 2000-2001, Aaron D. Gifford
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	* 3. Neither the name of the copyright holder nor the names of contributors
	* may be used to endorse or promote products derived from this software
	* without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTOR(S) ``AS IS'' AND
	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTOR(S) BE LIABLE
	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	* SUCH DAMAGE.
	*
	* $From: sha2.c,v 1.1 2001/11/08 00:01:51 adg Exp adg $
	*
	* contrib/pgcrypto/sha2.c
	*/

	#include <random/sha2.h>

	/* SHA-256/512 Various Length Definitions *********************/
	enum { SHA256ShortBlockLength = (SHA256BlockLength - 8),
	SHA512ShortBlockLength = (SHA512_block_length - 16) };

	/*
	* Macro for incrementally adding the unsigned 64-bit integer n to the
	* unsigned 128-bit integer (represented using a two-element array of
	* 64-bit words):
	*/
	#define ADDINC128(w, n) \
	{ \
	(w)[0] += (uint64_t)(n); \
	if ((w)[0] < (n)) { \
	(w)[1]++; \
	} \
	}

	/* THE SIX LOGICAL FUNCTIONS **************************************/
	/*
	* Bit shifting and rotation (used by the six SHA-XYZ logical functions:
	*
	* NOTE: The naming of R and S appears backwards here (R is a SHIFT and
	* S is a ROTATION) because the SHA-256/384/512 description document
	* (see http://csrc.nist.gov/cryptval/shs/sha256-384-512.pdf) uses this
	* same "backwards" definition.
	*/
	/* Shift-right (used in SHA-256, SHA-384, and SHA-512): */
	#define R(b, x) ((x) >> (b))
	/* 32-bit Rotate-right (used in SHA-256): */
	#define S32(b, x) (((x) >> (b)) \| ((x) << (32 - (b))))
	/* 64-bit Rotate-right (used in SHA-384 and SHA-512): */
	#define S64(b, x) (((x) >> (b)) \| ((x) << (64 - (b))))

	/* Two of six logical functions used in SHA-256, SHA-384, and SHA-512: */
	#define Ch(x, y, z) (((x) & (y)) ^ ((~(x)) & (z)))
	#define Maj(x, y, z) (((x) & (y)) ^ ((x) & (z)) ^ ((y) & (z)))

	/* Four of six logical functions used in SHA-256: */
	#define Sigma0_256(x) (S32(2, (x)) ^ S32(13, (x)) ^ S32(22, (x)))
	#define Sigma1_256(x) (S32(6, (x)) ^ S32(11, (x)) ^ S32(25, (x)))
	#define sigma0_256(x) (S32(7, (x)) ^ S32(18, (x)) ^ R(3, (x)))
	#define sigma1_256(x) (S32(17, (x)) ^ S32(19, (x)) ^ R(10, (x)))

	/* Four of six logical functions used in SHA-384 and SHA-512: */
	#define Sigma0_512(x) (S64(28, (x)) ^ S64(34, (x)) ^ S64(39, (x)))
	#define Sigma1_512(x) (S64(14, (x)) ^ S64(18, (x)) ^ S64(41, (x)))
	#define sigma0_512(x) (S64(1, (x)) ^ S64(8, (x)) ^ R(7, (x)))
	#define sigma1_512(x) (S64(19, (x)) ^ S64(61, (x)) ^ R(6, (x)))

	/* INTERNAL FUNCTION PROTOTYPES ***********************************/
	/* NOTE: These should not be accessed directly from outside this
	* library -- they are intended for private internal visibility/use
	* only.
	*/
	static void SHA512_Last(SHA512Ctx *);
	static void SHA256_Transform(SHA256Ctx , const uint32_t );
	static void SHA512_Transform(SHA512Ctx , const uint64_t );

	/* SHA-XYZ INITIAL HASH VALUES AND CONSTANTS **********************/
	/* Hash constant words K for SHA-256: */
	const uint32_t 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};

	/* Initial hash value H for SHA-224: */
	const uint32_t sha224_initial_hash_value[8] = {
	0xc1059ed8UL, 0x367cd507UL, 0x3070dd17UL, 0xf70e5939UL,
	0xffc00b31UL, 0x68581511UL, 0x64f98fa7UL, 0xbefa4fa4UL};

	/* Initial hash value H for SHA-256: */
	static const uint32_t sha256_initial_hash_value[8] = {
	0x6a09e667UL, 0xbb67ae85UL, 0x3c6ef372UL, 0xa54ff53aUL,
	0x510e527fUL, 0x9b05688cUL, 0x1f83d9abUL, 0x5be0cd19UL};

	/* Hash constant words K for SHA-384 and SHA-512: */
	static const uint64_t K512[80] = {
	0x428a2f98d728ae22ULL, 0x7137449123ef65cdULL, 0xb5c0fbcfec4d3b2fULL,
	0xe9b5dba58189dbbcULL, 0x3956c25bf348b538ULL, 0x59f111f1b605d019ULL,
	0x923f82a4af194f9bULL, 0xab1c5ed5da6d8118ULL, 0xd807aa98a3030242ULL,
	0x12835b0145706fbeULL, 0x243185be4ee4b28cULL, 0x550c7dc3d5ffb4e2ULL,
	0x72be5d74f27b896fULL, 0x80deb1fe3b1696b1ULL, 0x9bdc06a725c71235ULL,
	0xc19bf174cf692694ULL, 0xe49b69c19ef14ad2ULL, 0xefbe4786384f25e3ULL,
	0x0fc19dc68b8cd5b5ULL, 0x240ca1cc77ac9c65ULL, 0x2de92c6f592b0275ULL,
	0x4a7484aa6ea6e483ULL, 0x5cb0a9dcbd41fbd4ULL, 0x76f988da831153b5ULL,
	0x983e5152ee66dfabULL, 0xa831c66d2db43210ULL, 0xb00327c898fb213fULL,
	0xbf597fc7beef0ee4ULL, 0xc6e00bf33da88fc2ULL, 0xd5a79147930aa725ULL,
	0x06ca6351e003826fULL, 0x142929670a0e6e70ULL, 0x27b70a8546d22ffcULL,
	0x2e1b21385c26c926ULL, 0x4d2c6dfc5ac42aedULL, 0x53380d139d95b3dfULL,
	0x650a73548baf63deULL, 0x766a0abb3c77b2a8ULL, 0x81c2c92e47edaee6ULL,
	0x92722c851482353bULL, 0xa2bfe8a14cf10364ULL, 0xa81a664bbc423001ULL,
	0xc24b8b70d0f89791ULL, 0xc76c51a30654be30ULL, 0xd192e819d6ef5218ULL,
	0xd69906245565a910ULL, 0xf40e35855771202aULL, 0x106aa07032bbd1b8ULL,
	0x19a4c116b8d2d0c8ULL, 0x1e376c085141ab53ULL, 0x2748774cdf8eeb99ULL,
	0x34b0bcb5e19b48a8ULL, 0x391c0cb3c5c95a63ULL, 0x4ed8aa4ae3418acbULL,
	0x5b9cca4f7763e373ULL, 0x682e6ff3d6b2b8a3ULL, 0x748f82ee5defb2fcULL,
	0x78a5636f43172f60ULL, 0x84c87814a1f0ab72ULL, 0x8cc702081a6439ecULL,
	0x90befffa23631e28ULL, 0xa4506cebde82bde9ULL, 0xbef9a3f7b2c67915ULL,
	0xc67178f2e372532bULL, 0xca273eceea26619cULL, 0xd186b8c721c0c207ULL,
	0xeada7dd6cde0eb1eULL, 0xf57d4f7fee6ed178ULL, 0x06f067aa72176fbaULL,
	0x0a637dc5a2c898a6ULL, 0x113f9804bef90daeULL, 0x1b710b35131c471bULL,
	0x28db77f523047d84ULL, 0x32caab7b40c72493ULL, 0x3c9ebe0a15c9bebcULL,
	0x431d67c49c100d4cULL, 0x4cc5d4becb3e42b6ULL, 0x597f299cfc657e2aULL,
	0x5fcb6fab3ad6faecULL, 0x6c44198c4a475817ULL};

	/* Initial hash value H for SHA-384 */
	static const uint64_t sha384_initial_hash_value[8] = {
	0xcbbb9d5dc1059ed8ULL, 0x629a292a367cd507ULL, 0x9159015a3070dd17ULL,
	0x152fecd8f70e5939ULL, 0x67332667ffc00b31ULL, 0x8eb44a8768581511ULL,
	0xdb0c2e0d64f98fa7ULL, 0x47b5481dbefa4fa4ULL};

	/* Initial hash value H for SHA-512 */
	static const uint64_t sha512_initial_hash_value[8] = {
	0x6a09e667f3bcc908ULL, 0xbb67ae8584caa73bULL, 0x3c6ef372fe94f82bULL,
	0xa54ff53a5f1d36f1ULL, 0x510e527fade682d1ULL, 0x9b05688c2b3e6c1fULL,
	0x1f83d9abfb41bd6bULL, 0x5be0cd19137e2179ULL};

	/* SHA-256: *******************************************************/
	void SHA256_Init(SHA256Ctx *context)
	{
	if (context == NULL)
	return;
	memmove(context->state, sha256_initial_hash_value, SHA256DigestLength);
	memset(context->buffer, 0, SHA256BlockLength);
	context->bitcount = 0;
	}
	static void SHA256_Transform(SHA256Ctx context, const uint32_t data)
	{
	uint32_t a, b, c, d, e, f, g, h, s0, s1;
	uint32_t T1, T2, *W256;
	int j;

	W256 = (uint32_t *)context->buffer;

	/* Initialize registers with the prev. intermediate value */
	a = context->state[0];
	b = context->state[1];
	c = context->state[2];
	d = context->state[3];
	e = context->state[4];
	f = context->state[5];
	g = context->state[6];
	h = context->state[7];

	j = 0;
	do {
	W256[j] = (uint32_t)data[3] \| ((uint32_t)data[2] << 8) \|
	((uint32_t)data[1] << 16) \| ((uint32_t)data[0] << 24);
	data += 4;
	/* Apply the SHA-256 compression function to update a..h */
	T1 = h + Sigma1_256(e) + Ch(e, f, g) + K256[j] + W256[j];
	T2 = Sigma0_256(a) + Maj(a, b, c);
	h = g;
	g = f;
	f = e;
	e = d + T1;
	d = c;
	c = b;
	b = a;
	a = T1 + T2;

	j++;
	} while (j < 16);

	do {
	/* Part of the message block expansion: */
	s0 = W256[(j + 1) & 0x0f];
	s0 = sigma0_256(s0);
	s1 = W256[(j + 14) & 0x0f];
	s1 = sigma1_256(s1);

	/* Apply the SHA-256 compression function to update a..h */
	T1 = h + Sigma1_256(e) + Ch(e, f, g) + K256[j] +
	(W256[j & 0x0f] += s1 + W256[(j + 9) & 0x0f] + s0);
	T2 = Sigma0_256(a) + Maj(a, b, c);
	h = g;
	g = f;
	f = e;
	e = d + T1;
	d = c;
	c = b;
	b = a;
	a = T1 + T2;

	j++;
	} while (j < 64);

	/* Compute the current intermediate hash value */
	context->state[0] += a;
	context->state[1] += b;
	context->state[2] += c;
	context->state[3] += d;
	context->state[4] += e;
	context->state[5] += f;
	context->state[6] += g;
	context->state[7] += h;

	/* Clean up */
	a = b = c = d = e = f = g = h = T1 = T2 = 0;
	}

	void SHA256_Update(SHA256Ctx context, const uint8_t data, size_t len)
	{
	size_t freespace, usedspace;

	/* Calling with no data is valid (we do nothing) */
	if (len == 0)
	return;

	usedspace = (context->bitcount >> 3) % SHA256BlockLength;
	if (usedspace > 0) {
	/* Calculate how much free space is available in the buffer */
	freespace = SHA256BlockLength - usedspace;

	if (len >= freespace) {
	/* Fill the buffer completely and process it */
	memmove(&context->buffer[usedspace], data, freespace);
	context->bitcount += freespace << 3;
	len -= freespace;
	data += freespace;
	SHA256_Transform(context, (uint32_t *)context->buffer);
	} else {
	/* The buffer is not yet full */
	memmove(&context->buffer[usedspace], data, len);
	context->bitcount += len << 3;
	/* Clean up: */
	usedspace = freespace = 0;
	return;
	}
	}
	while (len >= SHA256BlockLength) {
	/* Process as many complete blocks as we can */
	SHA256_Transform(context, (const uint32_t *)data);
	context->bitcount += SHA256BlockLength << 3;
	len -= SHA256BlockLength;
	data += SHA256BlockLength;
	}
	if (len > 0) {
	/* There's left-overs, so save 'em */
	memmove(context->buffer, data, len);
	context->bitcount += len << 3;
	}
	/* Clean up: */
	usedspace = freespace = 0;
	}

	static void SHA256_Last(SHA256Ctx *context)
	{
	unsigned int usedspace;

	usedspace = (context->bitcount >> 3) % SHA256BlockLength;

	if (usedspace > 0) {
	/* Begin padding with a 1 bit: */
	context->buffer[usedspace++] = 0x80;

	if (usedspace <= SHA256ShortBlockLength) {
	/* Set-up for the last transform: */
	memset(&context->buffer[usedspace], 0,
	SHA256ShortBlockLength - usedspace);
	} else {
	if (usedspace < SHA256BlockLength) {
	memset(&context->buffer[usedspace], 0,
	SHA256BlockLength - usedspace);
	}
	/* Do second-to-last transform: */
	SHA256_Transform(context, (uint32_t *)context->buffer);

	/* And set-up for the last transform: */
	memset(context->buffer, 0, SHA256ShortBlockLength);
	}
	} else {
	/* Set-up for the last transform: */
	memset(context->buffer, 0, SHA256ShortBlockLength);

	/* Begin padding with a 1 bit: */
	*context->buffer = 0x80;
	}
	/* Set the bit count: */
	(uint64_t )&context->buffer[SHA256ShortBlockLength] =
	context->bitcount;

	/* Final transform: */
	SHA256_Transform(context, (uint32_t *)context->buffer);
	}

	void SHA256_Final(uint8_t digest[], SHA256Ctx *context)
	{
	/* If no digest buffer is passed, we don't bother doing this: */
	if (digest != NULL) {
	SHA256_Last(context);

	memmove(digest, context->state, SHA256DigestLength);
	}

	/* Clean up state data: */
	memset(context, 0, sizeof(*context));
	}

	/* SHA-512: *******************************************************/
	void SHA512_Init(SHA512Ctx *context)
	{
	if (context == NULL)
	return;
	memmove(context->state, sha512_initial_hash_value, SHA512DigestLength);
	memset(context->buffer, 0, SHA512_block_length);
	context->bitcount[0] = context->bitcount[1] = 0;
	}

	static void SHA512_Transform(SHA512Ctx context, const uint64_t data)
	{
	uint64_t a, b, c, d, e, f, g, h, s0, s1;
	uint64_t T1, T2, W512 = (uint64_t )context->buffer;
	int j;

	/* Initialize registers with the prev. intermediate value */
	a = context->state[0];
	b = context->state[1];
	c = context->state[2];
	d = context->state[3];
	e = context->state[4];
	f = context->state[5];
	g = context->state[6];
	h = context->state[7];

	j = 0;
	do {
	W512[j] =
	(uint64_t)data[7] \| ((uint64_t)data[6] << 8) \|
	((uint64_t)data[5] << 16) \| ((uint64_t)data[4] << 24) \|
	((uint64_t)data[3] << 32) \| ((uint64_t)data[2] << 40) \|
	((uint64_t)data[1] << 48) \| ((uint64_t)data[0] << 56);
	data += 8;
	/* Apply the SHA-512 compression function to update a..h */
	T1 = h + Sigma1_512(e) + Ch(e, f, g) + K512[j] + W512[j];
	T2 = Sigma0_512(a) + Maj(a, b, c);
	h = g;
	g = f;
	f = e;
	e = d + T1;
	d = c;
	c = b;
	b = a;
	a = T1 + T2;

	j++;
	} while (j < 16);

	do {
	/* Part of the message block expansion: */
	s0 = W512[(j + 1) & 0x0f];
	s0 = sigma0_512(s0);
	s1 = W512[(j + 14) & 0x0f];
	s1 = sigma1_512(s1);

	/* Apply the SHA-512 compression function to update a..h */
	T1 = h + Sigma1_512(e) + Ch(e, f, g) + K512[j] +
	(W512[j & 0x0f] += s1 + W512[(j + 9) & 0x0f] + s0);
	T2 = Sigma0_512(a) + Maj(a, b, c);
	h = g;
	g = f;
	f = e;
	e = d + T1;
	d = c;
	c = b;
	b = a;
	a = T1 + T2;

	j++;
	} while (j < 80);

	/* Compute the current intermediate hash value */
	context->state[0] += a;
	context->state[1] += b;
	context->state[2] += c;
	context->state[3] += d;
	context->state[4] += e;
	context->state[5] += f;
	context->state[6] += g;
	context->state[7] += h;

	/* Clean up */
	a = b = c = d = e = f = g = h = T1 = T2 = 0;
	}

	void SHA512_Update(SHA512Ctx context, const uint8_t data, size_t len)
	{
	size_t freespace, usedspace;

	/* Calling with no data is valid (we do nothing) */
	if (len == 0)
	return;

	usedspace = (context->bitcount[0] >> 3) % SHA512_block_length;
	if (usedspace > 0) {
	/* Calculate how much free space is available in the buffer */
	freespace = SHA512_block_length - usedspace;

	if (len >= freespace) {
	/* Fill the buffer completely and process it */
	memmove(&context->buffer[usedspace], data, freespace);
	ADDINC128(context->bitcount, freespace << 3);
	len -= freespace;
	data += freespace;
	SHA512_Transform(context, (uint64_t *)context->buffer);
	} else {
	/* The buffer is not yet full */
	memmove(&context->buffer[usedspace], data, len);
	ADDINC128(context->bitcount, len << 3);
	/* Clean up: */
	usedspace = freespace = 0;
	return;
	}
	}
	while (len >= SHA512_block_length) {
	/* Process as many complete blocks as we can */
	SHA512_Transform(context, (const uint64_t *)data);
	ADDINC128(context->bitcount, SHA512_block_length << 3);
	len -= SHA512_block_length;
	data += SHA512_block_length;
	}
	if (len > 0) {
	/* There's left-overs, so save 'em */
	memmove(context->buffer, data, len);
	ADDINC128(context->bitcount, len << 3);
	}
	/* Clean up: */
	usedspace = freespace = 0;
	}

	static void SHA512_Last(SHA512Ctx *context)
	{
	unsigned int usedspace;

	usedspace = (context->bitcount[0] >> 3) % SHA512_block_length;

	if (usedspace > 0) {
	/* Begin padding with a 1 bit: */
	context->buffer[usedspace++] = 0x80;

	if (usedspace <= SHA512ShortBlockLength) {
	/* Set-up for the last transform: */
	memset(&context->buffer[usedspace], 0,
	SHA512ShortBlockLength - usedspace);
	} else {
	if (usedspace < SHA512_block_length) {
	memset(&context->buffer[usedspace], 0,
	SHA512_block_length - usedspace);
	}
	/* Do second-to-last transform: */
	SHA512_Transform(context, (uint64_t *)context->buffer);

	/* And set-up for the last transform: */
	memset(context->buffer, 0, SHA512_block_length - 2);
	}
	} else {
	/* Prepare for final transform: */
	memset(context->buffer, 0, SHA512ShortBlockLength);

	/* Begin padding with a 1 bit: */
	*context->buffer = 0x80;
	}
	/* Store the length of input data (in bits): */
	(uint64_t )&context->buffer[SHA512ShortBlockLength] =
	context->bitcount[1];
	(uint64_t )&context->buffer[SHA512ShortBlockLength + 8] =
	context->bitcount[0];

	/* Final transform: */
	SHA512_Transform(context, (uint64_t *)context->buffer);
	}

	void SHA512_Final(uint8_t digest[], SHA512Ctx *context)
	{
	/* If no digest buffer is passed, we don't bother doing this: */
	if (digest != NULL) {
	SHA512_Last(context);

	/* Save the hash data for output: */
	memmove(digest, context->state, SHA512DigestLength);
	}

	/* Zero out state data */
	memset(context, 0, sizeof(*context));
	}

	/* SHA-384: *******************************************************/
	void SHA384_Init(SHA384Ctx *context)
	{
	if (context == NULL)
	return;
	memmove(context->state, sha384_initial_hash_value, SHA512DigestLength);
	memset(context->buffer, 0, SHA384BlockLength);
	context->bitcount[0] = context->bitcount[1] = 0;
	}

	void SHA384_Update(SHA384Ctx context, const uint8_t data, size_t len)
	{
	SHA512_Update((SHA512Ctx *)context, data, len);
	}

	void SHA384_Final(uint8_t digest[], SHA384Ctx *context)
	{
	/* If no digest buffer is passed, we don't bother doing this: */
	if (digest != NULL) {
	SHA512_Last((SHA512Ctx *)context);

	/* Save the hash data for output: */
	memmove(digest, context->state, SHA384DigestLength);
	}

	/* Zero out state data */
	memset(context, 0, sizeof(*context));
	}

	/* SHA-224: *******************************************************/
	void SHA224_Init(SHA224Ctx *context)
	{
	if (context == NULL)
	return;
	memmove(context->state, sha224_initial_hash_value, SHA256DigestLength);
	memset(context->buffer, 0, SHA256BlockLength);
	context->bitcount = 0;
	}

	void SHA224_Update(SHA224Ctx context, const uint8_t data, size_t len)
	{
	SHA256_Update((SHA256Ctx *)context, data, len);
	}

	void SHA224_Final(uint8_t digest[], SHA224Ctx *context)
	{
	/* If no digest buffer is passed, we don't bother doing this: */
	if (digest != NULL) {
	SHA256_Last(context);

	memmove(digest, context->state, SHA224DigestLength);
	}

	/* Clean up state data: */
	memset(context, 0, sizeof(*context));
	}