I have tried a few different sha2 sources I could find so far the best single solution for the 4 sha2 types I need is https://github.com/kalven/sha-2 unfortunately it will not compile for an embedded environment because it is c++11.

I found a nice basic sha2 implentation here http://bradconte.com/sha256_c but it only does sha2 256.

All the searches I do I keep finding implementations that are part of a bigger dependency like ssl or bitcoin and such.

Does anyone know of a c/c++ compatible sha2 implementation that contains 224, 256, 384, and 512 that has no dependencies?

From the looks of it, the only C++11 thing it's using is the header <cstdint>, and the std::uint64_t variable typedefs.

All you need to do to port it is Ctrl+F replace <cstdint> (C++11) for <stdint.h> (C99), and replace all occurances of "std::uint" (such as in std::uint64_t) with "uint" (without the "std::" part).

Unless I missed something, that should do it. It doesn't look like it's using any C++11 features, just the C++11 long long int type, which is also in C99 which most compilers include even though it wasn't officially added to C++ until C++11 (see an example compiling the large ints here).

From the looks of it, the only C++11 thing it's using is the header <cstdint>, and the std::uint64_t variable typedefs.

All you need to do to port it is Ctrl+F replace <cstdint> (C++11) for <stdint.h> (C99), and replace all occurances of "std::uint" (such as in std::uint64_t) with "uint" (without the "std::" part).

Unless I missed something, that should do it. It doesn't look like it's using any C++11 features, just the C++11 long long int type, which is also in C99 which most compilers include even though it wasn't officially added to C++ until C++11 (see an example compiling the large ints here).

You'll also find some auto types and lambda expressions in there, although they are almost just as trivial to replace with their non-C++11 counterpart.

You'll also find some auto types and lambda expressions in there, although they are almost just as trivial to replace with their non-C++11 counterpart.

Ah, now I see it, totally missed it.

In sha256.cpp and sha512.cpp

Ctrl+F and replace this:

auto in = static_cast<const unsigned char*>(src);

With this:

const unsigned char* in = static_cast<const unsigned char*>(src);

Also in both of those files, you'll find a piece of code like this:

auto RND = [&]( parameters )
{
        //...code
};

They need to be converted to regular functions outside of the function they are in. The variables t0 and t1 can be made local to the new 'RND' function instead of local to the sha_compress function.

Basically, use this as your new sha256.cpp :

// SHA-256. Adapted from LibTomCrypt. This code is Public Domain
#include "sha256.hpp"

#include <cstring>

typedef uint32_t u32;
typedef uint64_t u64;

static const u32 K[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
};

static u32 min(u32 x, u32 y)
{
    return x < y ? x : y;
}

static u32 load32(const unsigned char* y)
{
    return (u32(y[0]) << 24) | (u32(y[1]) << 16) | (u32(y[2]) << 8) | (u32(y[3]) << 0);
}

static void store64(u64 x, unsigned char* y)
{
    for(int i = 0; i != 8; ++i)
        y[i] = (x >> ((7-i) * 8)) & 255;
}

static void store32(u32 x, unsigned char* y)
{
    for(int i = 0; i != 4; ++i)
        y[i] = (x >> ((3-i) * 8)) & 255;
}

static u32 Ch(u32 x, u32 y, u32 z)  { return z ^ (x & (y ^ z)); }
static u32 Maj(u32 x, u32 y, u32 z) { return ((x | y) & z) | (x & y); }
static u32 Rot(u32 x, u32 n)        { return (x >> (n & 31)) | (x << (32 - (n & 31))); }
static u32 Sh(u32 x, u32 n)         { return x >> n; }
static u32 Sigma0(u32 x)            { return Rot(x, 2) ^ Rot(x, 13) ^ Rot(x, 22); }
static u32 Sigma1(u32 x)            { return Rot(x, 6) ^ Rot(x, 11) ^ Rot(x, 25); }
static u32 Gamma0(u32 x)            { return Rot(x, 7) ^ Rot(x, 18) ^ Sh(x, 3); }
static u32 Gamma1(u32 x)            { return Rot(x, 17) ^ Rot(x, 19) ^ Sh(x, 10); }

void RND(u32 a, u32 b, u32 c, u32& d, u32 e, u32 f, u32 g, u32& h, u32 i)
{
        u32 t0 = h + Sigma1(e) + Ch(e, f, g) + K[i] + W[i];
        u32 t1 = Sigma0(a) + Maj(a, b, c);
        d += t0;
        h  = t0 + t1;
}

static void sha_compress(sha256_state& md, const unsigned char* buf)
{
    u32 S[8], W[64], t;

    // Copy state into S
    for(int i = 0; i < 8; i++)
        S[i] = md.state[i];

    // Copy the state into 512-bits into W[0..15]
    for(int i = 0; i < 16; i++)
        W[i] = load32(buf + (4*i));

    // Fill W[16..63]
    for(int i = 16; i < 64; i++)
        W[i] = Gamma1(W[i - 2]) + W[i - 7] + Gamma0(W[i - 15]) + W[i - 16];

    for(int i = 0; i < 64; ++i)
    {
        RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],i);
        t = S[7]; S[7] = S[6]; S[6] = S[5]; S[5] = S[4];
        S[4] = S[3]; S[3] = S[2]; S[2] = S[1]; S[1] = S[0]; S[0] = t;
    }

    // Feedback
    for(int i = 0; i < 8; i++)
        md.state[i] = md.state[i] + S[i];
}

// Public interface

void sha_init(sha256_state& md)
{
    md.curlen = 0;
    md.length = 0;
    md.state[0] = 0x6A09E667UL;
    md.state[1] = 0xBB67AE85UL;
    md.state[2] = 0x3C6EF372UL;
    md.state[3] = 0xA54FF53AUL;
    md.state[4] = 0x510E527FUL;
    md.state[5] = 0x9B05688CUL;
    md.state[6] = 0x1F83D9ABUL;
    md.state[7] = 0x5BE0CD19UL;
}

void sha_process(sha256_state& md, const void* src, u32 inlen)
{
    const u32 block_size = sizeof(sha256_state::buf);
    const unsigned char* in = static_cast<const unsigned char*>(src);

    while(inlen > 0)
    {
        if(md.curlen == 0 && inlen >= block_size)
        {
            sha_compress(md, in);
            md.length += block_size * 8;
            in        += block_size;
            inlen     -= block_size;
        }
        else
        {
            u32 n = min(inlen, (block_size - md.curlen));
            std::memcpy(md.buf + md.curlen, in, n);
            md.curlen += n;
            in        += n;
            inlen     -= n;

            if(md.curlen == block_size)
            {
                sha_compress(md, md.buf);
                md.length += 8*block_size;
                md.curlen = 0;
            }
        }
    }
}

void sha_done(sha256_state& md, void* out)
{
    // Increase the length of the message
    md.length += md.curlen * 8;

    // Append the '1' bit
    md.buf[md.curlen++] = static_cast<unsigned char>(0x80);

    // If the length is currently above 56 bytes we append zeros then compress.
    // Then we can fall back to padding zeros and length encoding like normal.
    if(md.curlen > 56)
    {
        while(md.curlen < 64)
            md.buf[md.curlen++] = 0;
        sha_compress(md, md.buf);
        md.curlen = 0;
    }

    // Pad upto 56 bytes of zeroes
    while(md.curlen < 56)
        md.buf[md.curlen++] = 0;

    // Store length
    store64(md.length, md.buf+56);
    sha_compress(md, md.buf);

    // Copy output
    for(int i = 0; i < 8; i++)
        store32(md.state[i], static_cast<unsigned char*>(out)+(4*i));
}

And this as your new sha512.cpp :

// SHA-512. Adapted from LibTomCrypt. This code is Public Domain
#include "sha512.hpp"

#include <cstring>

typedef uint32_t u32;
typedef uint64_t u64;

static const u64 K[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
};

static u32 min(u32 x, u32 y)
{
    return x < y ? x : y;
}

static void store64(u64 x, unsigned char* y)
{
    for(int i = 0; i != 8; ++i)
        y[i] = (x >> ((7-i) * 8)) & 255;
}

static u64 load64(const unsigned char* y)
{
    u64 res = 0;
    for(int i = 0; i != 8; ++i)
        res |= u64(y[i]) << ((7-i) * 8);
    return res;
}

static u64 Ch(u64 x, u64 y, u64 z)  { return z ^ (x & (y ^ z)); }
static u64 Maj(u64 x, u64 y, u64 z) { return ((x | y) & z) | (x & y); }
static u64 Rot(u64 x, u64 n)        { return (x >> (n & 63)) | (x << (64 - (n & 63))); }
static u64 Sh(u64 x, u64 n)         { return x >> n; }
static u64 Sigma0(u64 x)            { return Rot(x, 28) ^ Rot(x, 34) ^ Rot(x, 39); }
static u64 Sigma1(u64 x)            { return Rot(x, 14) ^ Rot(x, 18) ^ Rot(x, 41); }
static u64 Gamma0(u64 x)            { return Rot(x, 1) ^ Rot(x, 8) ^ Sh(x, 7); }
static u64 Gamma1(u64 x)            { return Rot(x, 19) ^ Rot(x, 61) ^ Sh(x, 6); }

void RND(u64 a, u64 b, u64 c, u64& d, u64 e, u64 f, u64 g, u64& h, u64 i)
{
        u64 t0 = h + Sigma1(e) + Ch(e, f, g) + K[i] + W[i];
        u64 t1 = Sigma0(a) + Maj(a, b, c);
        d += t0;
        h  = t0 + t1;
}

static void sha_compress(sha512_state& md, const unsigned char *buf)
{
    u64 S[8], W[80];

    // Copy state into S
    for(int i = 0; i < 8; i++)
        S[i] = md.state[i];

    // Copy the state into 1024-bits into W[0..15]
    for(int i = 0; i < 16; i++)
        W[i] = load64(buf + (8*i));

    // Fill W[16..79]
    for(int i = 16; i < 80; i++)
        W[i] = Gamma1(W[i - 2]) + W[i - 7] + Gamma0(W[i - 15]) + W[i - 16];

    for(int 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);
    }

     // Feedback
     for(int i = 0; i < 8; i++)
         md.state[i] = md.state[i] + S[i];
}

// Public interface

void sha_init(sha512_state& md)
{
    md.curlen = 0;
    md.length = 0;
    md.state[0] = 0x6a09e667f3bcc908ULL;
    md.state[1] = 0xbb67ae8584caa73bULL;
    md.state[2] = 0x3c6ef372fe94f82bULL;
    md.state[3] = 0xa54ff53a5f1d36f1ULL;
    md.state[4] = 0x510e527fade682d1ULL;
    md.state[5] = 0x9b05688c2b3e6c1fULL;
    md.state[6] = 0x1f83d9abfb41bd6bULL;
    md.state[7] = 0x5be0cd19137e2179ULL;
}

void sha_process(sha512_state& md, const void* src, u32 inlen)
{
    const u32 block_size = sizeof(sha512_state::buf);
    const unsigned char* in = static_cast<const unsigned char*>(src);

    while(inlen > 0)
    {
        if(md.curlen == 0 && inlen >= block_size)
        {
            sha_compress(md, in);
            md.length += block_size * 8;
            in        += block_size;
            inlen     -= block_size;
        }
        else
        {
            u32 n = min(inlen, (block_size - md.curlen));
            std::memcpy(md.buf + md.curlen, in, n);
            md.curlen += n;
            in        += n;
            inlen     -= n;

            if(md.curlen == block_size)
            {
                sha_compress(md, md.buf);
                md.length += 8*block_size;
                md.curlen = 0;
            }
        }
    }
}

void sha_done(sha512_state& md, void *out)
{
    // Increase the length of the message
    md.length += md.curlen * 8ULL;

    // Append the '1' bit
    md.buf[md.curlen++] = static_cast<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.curlen > 112)
    {
        while(md.curlen < 128)
            md.buf[md.curlen++] = 0;
        sha_compress(md, md.buf);
        md.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.curlen < 120)
        md.buf[md.curlen++] = 0;

    // Store length
    store64(md.length, md.buf+120);
    sha_compress(md, md.buf);

    // Copy output
    for(int i = 0; i < 8; i++)
        store64(md.state[i], static_cast<unsigned char*>(out)+(8*i));
}

...in addition to the changes I mentioned in my first post.

Assuming the code worked in the first place, this should be fine. I'm not familiar with the algorithms themselves, just with C++ and C++11.

Did I miss anything else?

I have tried to back-port it and I can get the variable types fixed and the in part but when trying to do the auto part I messed it all up.

@Servant of the Lord

Thanks but im having an issue im trying the sha256 first and copied the sha256.cpp you have there and im getting an error

sha256.cpp:59:55: error: ‘W’ was not declared in this scope

Is that a typo is it supposed to be K?

W is local variable in sha_compress function - you need to pass it to RND function in argument.

Thanks that works perfectly now!