telodendria/Cytoplasm/src/Sha/Sha1.c

/*
 * Copyright (C) 2022-2023 Jordan Bancino <@jordan:bancino.net>
 *
 * Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation files
 * (the "Software"), to deal in the Software without restriction,
 * including without limitation the rights to use, copy, modify, merge,
 * publish, distribute, sublicense, and/or sell copies of the Software,
 * and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or portions of the Software.
 *
 * 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 <Sha.h>
#include <Memory.h>
#include <Int.h>

#include <string.h>

#include <limits.h>

#define LOAD32H(x, y) \
	{ \
		x = ((UInt32)((y)[0] & 255) << 24) | \
			((UInt32)((y)[1] & 255) << 16) | \
			((UInt32)((y)[2] & 255) <<  8) | \
			((UInt32)((y)[3] & 255));        \
	}

#define ROL(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))

#define BLK(i) (block->l[i & 15] = ROL(block->l[(i+13) & 15] ^ block->l[(i + 8) & 15] ^ block->l[(i + 2) & 15] ^ block->l[i & 15], 1))

#define R0(v, w, x, y, z, i) z += ((w & (x ^ y)) ^ y) + block->l[i] + 0x5A827999 + ROL(v, 5); w = ROL(w, 30);
#define R1(v, w, x, y, z, i) z += ((w & (x ^ y)) ^ y) + BLK(i) + 0x5A827999 + ROL(v, 5); w = ROL(w, 30);
#define R2(v, w, x, y, z, i) z += (w ^ x ^ y) + BLK(i) + 0x6ED9EBA1 + ROL(v, 5); w = ROL(w, 30);
#define R3(v, w, x, y, z, i) z += (((w | x) & y) | (w & x)) + BLK(i) + 0x8F1BBCDC + ROL(v, 5); w = ROL(w, 30);
#define R4(v, w, x, y, z, i) z += (w ^ x ^ y) + BLK(i) + 0xCA62C1D6 + ROL(v, 5); w = ROL(w, 30);

typedef union
{
    UInt8 c[64];
    UInt32 l[16];
} Char64Long16;

typedef struct
{
    UInt32 state[5];
    UInt32 count[2];
    UInt8 buffer[64];
} Sha1Context;

static void
Sha1Transform(UInt32 state[5], const UInt8 buffer[64])
{
    UInt32 a, b, c, d, e, i;
    UInt8 workspace[64];
    Char64Long16 *block = (Char64Long16 *) workspace;

    for (i = 0; i < 16; i++)
    {
        LOAD32H(block->l[i], buffer + (i * 4));
    }

    a = state[0];
    b = state[1];
    c = state[2];
    d = state[3];
    e = state[4];

    R0(a, b, c, d, e, 0);
    R0(e, a, b, c, d, 1);
    R0(d, e, a, b, c, 2);
    R0(c, d, e, a, b, 3);
    R0(b, c, d, e, a, 4);
    R0(a, b, c, d, e, 5);
    R0(e, a, b, c, d, 6);
    R0(d, e, a, b, c, 7);
    R0(c, d, e, a, b, 8);
    R0(b, c, d, e, a, 9);
    R0(a, b, c, d, e, 10);
    R0(e, a, b, c, d, 11);
    R0(d, e, a, b, c, 12);
    R0(c, d, e, a, b, 13);
    R0(b, c, d, e, a, 14);
    R0(a, b, c, d, e, 15);
    R1(e, a, b, c, d, 16);
    R1(d, e, a, b, c, 17);
    R1(c, d, e, a, b, 18);
    R1(b, c, d, e, a, 19);
    R2(a, b, c, d, e, 20);
    R2(e, a, b, c, d, 21);
    R2(d, e, a, b, c, 22);
    R2(c, d, e, a, b, 23);
    R2(b, c, d, e, a, 24);
    R2(a, b, c, d, e, 25);
    R2(e, a, b, c, d, 26);
    R2(d, e, a, b, c, 27);
    R2(c, d, e, a, b, 28);
    R2(b, c, d, e, a, 29);
    R2(a, b, c, d, e, 30);
    R2(e, a, b, c, d, 31);
    R2(d, e, a, b, c, 32);
    R2(c, d, e, a, b, 33);
    R2(b, c, d, e, a, 34);
    R2(a, b, c, d, e, 35);
    R2(e, a, b, c, d, 36);
    R2(d, e, a, b, c, 37);
    R2(c, d, e, a, b, 38);
    R2(b, c, d, e, a, 39);
    R3(a, b, c, d, e, 40);
    R3(e, a, b, c, d, 41);
    R3(d, e, a, b, c, 42);
    R3(c, d, e, a, b, 43);
    R3(b, c, d, e, a, 44);
    R3(a, b, c, d, e, 45);
    R3(e, a, b, c, d, 46);
    R3(d, e, a, b, c, 47);
    R3(c, d, e, a, b, 48);
    R3(b, c, d, e, a, 49);
    R3(a, b, c, d, e, 50);
    R3(e, a, b, c, d, 51);
    R3(d, e, a, b, c, 52);
    R3(c, d, e, a, b, 53);
    R3(b, c, d, e, a, 54);
    R3(a, b, c, d, e, 55);
    R3(e, a, b, c, d, 56);
    R3(d, e, a, b, c, 57);
    R3(c, d, e, a, b, 58);
    R3(b, c, d, e, a, 59);
    R4(a, b, c, d, e, 60);
    R4(e, a, b, c, d, 61);
    R4(d, e, a, b, c, 62);
    R4(c, d, e, a, b, 63);
    R4(b, c, d, e, a, 64);
    R4(a, b, c, d, e, 65);
    R4(e, a, b, c, d, 66);
    R4(d, e, a, b, c, 67);
    R4(c, d, e, a, b, 68);
    R4(b, c, d, e, a, 69);
    R4(a, b, c, d, e, 70);
    R4(e, a, b, c, d, 71);
    R4(d, e, a, b, c, 72);
    R4(c, d, e, a, b, 73);
    R4(b, c, d, e, a, 74);
    R4(a, b, c, d, e, 75);
    R4(e, a, b, c, d, 76);
    R4(d, e, a, b, c, 77);
    R4(c, d, e, a, b, 78);
    R4(b, c, d, e, a, 79);

    state[0] += a;
    state[1] += b;
    state[2] += c;
    state[3] += d;
    state[4] += e;
}

static void
Sha1Init(Sha1Context * ctx)
{
    ctx->state[0] = 0x67452301;
    ctx->state[1] = 0xEFCDAB89;
    ctx->state[2] = 0x98BADCFE;
    ctx->state[3] = 0x10325476;
    ctx->state[4] = 0xC3D2E1F0;

    ctx->count[0] = 0;
    ctx->count[1] = 0;
}

static void
Sha1Update(Sha1Context * ctx, const void *buf, UInt32 size)
{
    UInt32 i, j;

    j = (ctx->count[0] >> 3) & 63;

    if ((ctx->count[0] += size << 3) < (size << 3))
    {
        ctx->count[1]++;
    }

    ctx->count[1] += (size >> 29);

    if ((j + size) > 63)
    {
        i = 64 - j;

        memcpy(&ctx->buffer[j], buf, i);
        Sha1Transform(ctx->state, ctx->buffer);

        for (; i + 63 < size; i += 64)
        {
            Sha1Transform(ctx->state, (UInt8 *) buf + i);
        }

        j = 0;
    }
    else
    {
        i = 0;
    }

    memcpy(&ctx->buffer[j], &((UInt8 *) buf)[i], size - i);
}

static void
Sha1Calculate(Sha1Context * ctx, unsigned char *out)
{
    UInt32 i;
    UInt8 count[8];

    for (i = 0; i < 8; i++)
    {
        count[i] = (unsigned char) ((ctx->count[(i >= 4 ? 0 : 1)]
                                     >> ((3 - (i & 3)) * 8)) & 255);
    }

    Sha1Update(ctx, (UInt8 *) "\x80", 1);
    while ((ctx->count[0] & 504) != 448)
    {
        Sha1Update(ctx, (UInt8 *) "\0", 1);
    }

    Sha1Update(ctx, count, 8);
    for (i = 0; i < (160 / 8); i++)
    {
        out[i] = (UInt8) ((ctx->state[i >> 2] >> ((3 - (i & 3)) * 8)) & 255);
    }
}

unsigned char *
Sha1(char *str)
{
    Sha1Context ctx;
    unsigned char *out;

    if (!str)
    {
        return NULL;
    }

    out = Malloc(((160 / 8) + 1) * sizeof(unsigned char));
    if (!out)
    {
        return NULL;
    }

    Sha1Init(&ctx);
    Sha1Update(&ctx, str, strlen(str));
    Sha1Calculate(&ctx, out);

    out[160 / 8] = '\0';

    return out;
}