C++ sha512 function


SHA-512 is the largest hash function in the SHA-2 family of hash functions. SHA-512 provides 256 bits of security to digital signatures and hash-only applications.

If SHA-512 is to be used for password hashing, select a good work factor. For instance, apply 2^8 (256) rounds of SHA-512, and store 8 as your work factor along with the hashed password. Later, you can increase your work factor and then still verify older passwords. Use a unique random salt for each password hash, and store that next to the hashed password as well. A unique random salt protects your passwords by making dictionary attacks much harder.

main.cpp
#include <iostream>
#include "sha512.h"
 
using std::string;
using std::cout;
using std::endl;
 
int main(int argc, char *argv[])
{
    string input = "grape";
    string output1 = sha512(input);
 
    cout << "sha512('"<< input << "'):" << output1 << endl;
    return 0;
}

compile and run (in linux):
g++ sha512.cpp main.cpp -o sha512_example && ./sha512_example

output:
sha512('grape'):9375d1abdb644a01955bccad12e2f5c2bd8a3e226187e548d99c559a99461453b980123746753d07c169c22a5d9cc75cb158f0e8d8c0e713559775b5e1391fc4

sha512.h
#ifndef SHA512_H
#define SHA512_H
#include <string>
 
class SHA512
{
protected:
    typedef unsigned char uint8;
    typedef unsigned int uint32;
    typedef unsigned long long uint64;
 
    const static uint64 sha512_k[];
    static const unsigned int SHA384_512_BLOCK_SIZE = (1024/8);
 
public:
    void init();
    void update(const unsigned char *message, unsigned int len);
    void final(unsigned char *digest);
    static const unsigned int DIGEST_SIZE = ( 512 / 8);
 
protected:
    void transform(const unsigned char *message, unsigned int block_nb);
    unsigned int m_tot_len;
    unsigned int m_len;
    unsigned char m_block[2 * SHA384_512_BLOCK_SIZE];
    uint64 m_h[8];
};
 
 
std::string sha512(std::string input);
 
#define SHA2_SHFR(x, n)    (x >> n)
#define SHA2_ROTR(x, n)   ((x >> n) | (x << ((sizeof(x) << 3) - n)))
#define SHA2_ROTL(x, n)   ((x << n) | (x >> ((sizeof(x) << 3) - n)))
#define SHA2_CH(x, y, z)  ((x & y) ^ (~x & z))
#define SHA2_MAJ(x, y, z) ((x & y) ^ (x & z) ^ (y & z))
#define SHA512_F1(x) (SHA2_ROTR(x, 28) ^ SHA2_ROTR(x, 34) ^ SHA2_ROTR(x, 39))
#define SHA512_F2(x) (SHA2_ROTR(x, 14) ^ SHA2_ROTR(x, 18) ^ SHA2_ROTR(x, 41))
#define SHA512_F3(x) (SHA2_ROTR(x,  1) ^ SHA2_ROTR(x,  8) ^ SHA2_SHFR(x,  7))
#define SHA512_F4(x) (SHA2_ROTR(x, 19) ^ SHA2_ROTR(x, 61) ^ SHA2_SHFR(x,  6))
#define SHA2_UNPACK32(x, str)                 \
{                                             \
    *((str) + 3) = (uint8) ((x)      );       \
    *((str) + 2) = (uint8) ((x) >>  8);       \
    *((str) + 1) = (uint8) ((x) >> 16);       \
    *((str) + 0) = (uint8) ((x) >> 24);       \
}
#define SHA2_UNPACK64(x, str)                 \
{                                             \
    *((str) + 7) = (uint8) ((x)      );       \
    *((str) + 6) = (uint8) ((x) >>  8);       \
    *((str) + 5) = (uint8) ((x) >> 16);       \
    *((str) + 4) = (uint8) ((x) >> 24);       \
    *((str) + 3) = (uint8) ((x) >> 32);       \
    *((str) + 2) = (uint8) ((x) >> 40);       \
    *((str) + 1) = (uint8) ((x) >> 48);       \
    *((str) + 0) = (uint8) ((x) >> 56);       \
}
#define SHA2_PACK64(str, x)                   \
{                                             \
    *(x) =   ((uint64) *((str) + 7)      )    \
           | ((uint64) *((str) + 6) <<  8)    \
           | ((uint64) *((str) + 5) << 16)    \
           | ((uint64) *((str) + 4) << 24)    \
           | ((uint64) *((str) + 3) << 32)    \
           | ((uint64) *((str) + 2) << 40)    \
           | ((uint64) *((str) + 1) << 48)    \
           | ((uint64) *((str) + 0) << 56);   \
}
 
#endif

sha512.cpp
#include <cstring>
#include <fstream>
#include "sha512.h"
 
const unsigned long long SHA512::sha512_k[80] = //ULL = uint64
            {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};
 
void SHA512::transform(const unsigned char *message, unsigned int block_nb)
{
    uint64 w[80];
    uint64 wv[8];
    uint64 t1, t2;
    const unsigned char *sub_block;
    int i, j;
    for (i = 0; i < (int) block_nb; i++) {
        sub_block = message + (i << 7);
        for (j = 0; j < 16; j++) {
            SHA2_PACK64(&sub_block[j << 3], &w[j]);
        }
        for (j = 16; j < 80; j++) {
            w[j] =  SHA512_F4(w[j -  2]) + w[j -  7] + SHA512_F3(w[j - 15]) + w[j - 16];
        }
        for (j = 0; j < 8; j++) {
            wv[j] = m_h[j];
        }
        for (j = 0; j < 80; j++) {
            t1 = wv[7] + SHA512_F2(wv[4]) + SHA2_CH(wv[4], wv[5], wv[6])
                + sha512_k[j] + w[j];
            t2 = SHA512_F1(wv[0]) + SHA2_MAJ(wv[0], wv[1], wv[2]);
            wv[7] = wv[6];
            wv[6] = wv[5];
            wv[5] = wv[4];
            wv[4] = wv[3] + t1;
            wv[3] = wv[2];
            wv[2] = wv[1];
            wv[1] = wv[0];
            wv[0] = t1 + t2;
        }
        for (j = 0; j < 8; j++) {
            m_h[j] += wv[j];
        }
 
    }
}
 
void SHA512::init()
{
    m_h[0] = 0x6a09e667f3bcc908ULL;
    m_h[1] = 0xbb67ae8584caa73bULL;
    m_h[2] = 0x3c6ef372fe94f82bULL;
    m_h[3] = 0xa54ff53a5f1d36f1ULL;
    m_h[4] = 0x510e527fade682d1ULL;
    m_h[5] = 0x9b05688c2b3e6c1fULL;
    m_h[6] = 0x1f83d9abfb41bd6bULL; 
    m_h[7] = 0x5be0cd19137e2179ULL;
    m_len = 0;
    m_tot_len = 0;
}
 
void SHA512::update(const unsigned char *message, unsigned int len)
{
    unsigned int block_nb;
    unsigned int new_len, rem_len, tmp_len;
    const unsigned char *shifted_message;
    tmp_len = SHA384_512_BLOCK_SIZE - m_len;
    rem_len = len < tmp_len ? len : tmp_len;
    memcpy(&m_block[m_len], message, rem_len);
    if (m_len + len < SHA384_512_BLOCK_SIZE) {
        m_len += len;
        return;
    }
    new_len = len - rem_len;
    block_nb = new_len / SHA384_512_BLOCK_SIZE;
    shifted_message = message + rem_len;
    transform(m_block, 1);
    transform(shifted_message, block_nb);
    rem_len = new_len % SHA384_512_BLOCK_SIZE;
    memcpy(m_block, &shifted_message[block_nb << 7], rem_len);
    m_len = rem_len;
    m_tot_len += (block_nb + 1) << 7;
}
 
void SHA512::final(unsigned char *digest)
{
    unsigned int block_nb;
    unsigned int pm_len;
    unsigned int len_b;
    int i;
    block_nb = 1 + ((SHA384_512_BLOCK_SIZE - 17)
                     < (m_len % SHA384_512_BLOCK_SIZE));
    len_b = (m_tot_len + m_len) << 3;
    pm_len = block_nb << 7;
    memset(m_block + m_len, 0, pm_len - m_len);
    m_block[m_len] = 0x80;
    SHA2_UNPACK32(len_b, m_block + pm_len - 4);
    transform(m_block, block_nb);
    for (i = 0 ; i < 8; i++) {
        SHA2_UNPACK64(m_h[i], &digest[i << 3]);
    }
}
 
std::string sha512(std::string input)
{
    unsigned char digest[SHA512::DIGEST_SIZE];
    memset(digest,0,SHA512::DIGEST_SIZE);
    SHA512 ctx = SHA512();
    ctx.init();
    ctx.update((unsigned char*)input.c_str(), input.length());
    ctx.final(digest);
 
    char buf[2*SHA512::DIGEST_SIZE+1];
    buf[2*SHA512::DIGEST_SIZE] = 0;
    for (int i = 0; i < SHA512::DIGEST_SIZE; i++)
        sprintf(buf+i*2, "%02x", digest[i]);
    return std::string(buf);
}

LICENSE.txt
/*
 * Updated to C++, zedwood.com 2012
 * Based on Olivier Gay's version
 * See Modified BSD License below: 
 *
 * FIPS 180-2 SHA-224/256/384/512 implementation
 * Issue date:  04/30/2005
 * http://www.ouah.org/ogay/sha2/
 *
 * Copyright (C) 2005, 2007 Olivier Gay <olivier.gay@a3.epfl.ch>
 * 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 project nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``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 PROJECT OR CONTRIBUTORS 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.
 */

Dave McKellar on 2015-05-12 23:30:30
I would move the macros like
#define SHA2_SHFR(x, n) (x &gt;&gt; n)
to the .cpp file.