/*
 * An implementation of the SHA-512 hash function.
 *
 * The Federal Information Processing Standards (FIPS) Specification 
 * can be found here (FIPS 180-3):
 *   http://csrc.nist.gov/publications/PubsFIPS.html
 * 
 * Written in 2010 by Lorenz Quack <don@amberfisharts.com>
 *
 * ===================================================================
 * The contents of this file are dedicated to the public domain.  To
 * the extent that dedication to the public domain is not available,
 * everyone is granted a worldwide, perpetual, royalty-free,
 * non-exclusive license to exercise all rights associated with the
 * contents of this file for any purpose whatsoever.
 * No rights are reserved.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 * ===================================================================
 *
 */

#include "pycrypto_common.h"

#define MODULE_NAME SHA512
#define DIGEST_SIZE (512/8)
#define BLOCK_SIZE (1024/8)
#define WORD_SIZE 8
#define SCHEDULE_SIZE 80

static char MODULE__doc__[] =
    "SHA-512 cryptographic hash algorithm.\n"
    "\n"
    "SHA-512 belongs to the SHA-2_ family of cryptographic hashes.\n"
    "It produces the 512 bit digest of a message.\n"
    "\n"
    "    >>> from Crypto.Hash import SHA512\n"
    "    >>>\n"
    "    >>> h = SHA512.new()\n"
    "    >>> h.update(b'Hello')\n"
    "    >>> print h.hexdigest()\n"
    "\n"
    "*SHA* stands for Secure Hash Algorithm.\n"
    "\n"
    ".. _SHA-2: http://csrc.nist.gov/publications/fips/fips180-4/fips-180-4.pdf\n"
    "\n"
    ":Variables:\n"
    " block_size\n"
    "    The internal block size of the hash algorithm in bytes.\n"
    " digest_size\n"
    "    The size of the resulting hash in bytes.\n";

#include "hash_SHA2.h"

/* Initial Values H */
static const sha2_word_t H[8] = {
    0x6a09e667f3bcc908,
    0xbb67ae8584caa73b,
    0x3c6ef372fe94f82b,
    0xa54ff53a5f1d36f1,
    0x510e527fade682d1,
    0x9b05688c2b3e6c1f,
    0x1f83d9abfb41bd6b,
    0x5be0cd19137e2179
};

/* the Constants K */
static const sha2_word_t K[SCHEDULE_SIZE] = {
    0x428a2f98d728ae22, 0x7137449123ef65cd, 0xb5c0fbcfec4d3b2f, 0xe9b5dba58189dbbc, 
    0x3956c25bf348b538, 0x59f111f1b605d019, 0x923f82a4af194f9b, 0xab1c5ed5da6d8118,
    0xd807aa98a3030242, 0x12835b0145706fbe, 0x243185be4ee4b28c, 0x550c7dc3d5ffb4e2,
    0x72be5d74f27b896f, 0x80deb1fe3b1696b1, 0x9bdc06a725c71235, 0xc19bf174cf692694,
    0xe49b69c19ef14ad2, 0xefbe4786384f25e3, 0x0fc19dc68b8cd5b5, 0x240ca1cc77ac9c65,
    0x2de92c6f592b0275, 0x4a7484aa6ea6e483, 0x5cb0a9dcbd41fbd4, 0x76f988da831153b5,
    0x983e5152ee66dfab, 0xa831c66d2db43210, 0xb00327c898fb213f, 0xbf597fc7beef0ee4,
    0xc6e00bf33da88fc2, 0xd5a79147930aa725, 0x06ca6351e003826f, 0x142929670a0e6e70,
    0x27b70a8546d22ffc, 0x2e1b21385c26c926, 0x4d2c6dfc5ac42aed, 0x53380d139d95b3df, 
    0x650a73548baf63de, 0x766a0abb3c77b2a8, 0x81c2c92e47edaee6, 0x92722c851482353b, 
    0xa2bfe8a14cf10364, 0xa81a664bbc423001, 0xc24b8b70d0f89791, 0xc76c51a30654be30,
    0xd192e819d6ef5218, 0xd69906245565a910, 0xf40e35855771202a, 0x106aa07032bbd1b8,
    0x19a4c116b8d2d0c8, 0x1e376c085141ab53, 0x2748774cdf8eeb99, 0x34b0bcb5e19b48a8, 
    0x391c0cb3c5c95a63, 0x4ed8aa4ae3418acb, 0x5b9cca4f7763e373, 0x682e6ff3d6b2b8a3,
    0x748f82ee5defb2fc, 0x78a5636f43172f60, 0x84c87814a1f0ab72, 0x8cc702081a6439ec,
    0x90befffa23631e28, 0xa4506cebde82bde9, 0xbef9a3f7b2c67915, 0xc67178f2e372532b,
    0xca273eceea26619c, 0xd186b8c721c0c207, 0xeada7dd6cde0eb1e, 0xf57d4f7fee6ed178, 
    0x06f067aa72176fba, 0x0a637dc5a2c898a6, 0x113f9804bef90dae, 0x1b710b35131c471b,
    0x28db77f523047d84, 0x32caab7b40c72493, 0x3c9ebe0a15c9bebc, 0x431d67c49c100d4c,
    0x4cc5d4becb3e42b6, 0x597f299cfc657e2a, 0x5fcb6fab3ad6faec, 0x6c44198c4a475817
};

/* SHA-512 specific functions */
#define Sigma0(x)   (ROTR(x, 28) ^ ROTR(x, 34) ^ ROTR(x, 39))
#define Sigma1(x)   (ROTR(x, 14) ^ ROTR(x, 18) ^ ROTR(x, 41))
#define Gamma0(x)   (ROTR(x,  1) ^ ROTR(x,  8) ^ SHR(x,  7))
#define Gamma1(x)   (ROTR(x, 19) ^ ROTR(x, 61) ^ SHR(x,  6))

#include "hash_SHA2_template.c"