/*
 * Copyright (C) 2017 Nagravision S.A.
 */

#include "haraka.h"
#include <string.h>


void aesenc (uint8_t *s, const uint8_t *rk) {
    uint8_t i, t, u, v[4][4];
    for (i = 0; i < 16; ++i) v[((i / 4) + 4 - (i % 4)) % 4][i % 4] = sbox[s[i]];
    for (i = 0; i < 4; ++i) {
        t = v[i][0];
        u = v[i][0] ^ v[i][1] ^ v[i][2] ^ v[i][3];
        v[i][0] ^= u ^ XT (v[i][0] ^ v[i][1]);
        v[i][1] ^= u ^ XT (v[i][1] ^ v[i][2]);
        v[i][2] ^= u ^ XT (v[i][2] ^ v[i][3]);
        v[i][3] ^= u ^ XT (v[i][3] ^ t);
    }
    for (i = 0; i < 16; ++i) s[i] = v[i / 4][i % 4] ^ rk[i];
}


void haraka256_256 (uint8_t *out, const uint8_t *in) {

    uint8_t s0[16], s1[16];
    uint32_t tmp[4];
    int i;

    memcpy (s0, in, 16);
    memcpy (s1, in + 16, 16);

    AES2 (0);
    MIX2;
    AES2 (4);
    MIX2;
    AES2 (8);
    MIX2;
    AES2 (12);
    MIX2;
    AES2 (16);
    MIX2;
    AES2 (20);
    MIX2;

    for (i = 0; i < 16; ++i) {
        out[i] = in[i] ^ s0[i];
        out[i + 16] = in[i + 16] ^ s1[i];
    }
}

void haraka256_256_chain (uint8_t *out, const uint8_t *in, int chainlen) {

    uint8_t s0[16], s1[16];
    uint8_t t0[16], t1[16];
    uint32_t tmp[4];
    int i, j;

    memcpy (s0, in, 16);
    memcpy (s1, in + 16, 16);
    memcpy (t0, in, 16);
    memcpy (t1, in + 16, 16);

    for (j = 0; j < chainlen; ++j) {

        AES2 (0);
        MIX2;
        AES2 (4);
        MIX2;
        AES2 (8);
        MIX2;
        AES2 (12);
        MIX2;
        AES2 (16);
        MIX2;
        AES2 (20);
        MIX2;

        for (i = 0; i < 16; ++i) {
            s0[i] = t0[i] = t0[i] ^ s0[i];
            s1[i] = t1[i] = t1[i] ^ s1[i];
        }
    }
    for (i = 0; i < 16; ++i) {
        out[i] = s0[i];
        out[i + 16] = s1[i];
    }
}

void haraka512_256 (uint8_t *out, const uint8_t *in) {

    uint8_t s0[16], s1[16], s2[16], s3[16];
    uint32_t tmp[5];
    int i;

    memcpy (s0, in, 16);
    memcpy (s1, in + 16, 16);
    memcpy (s2, in + 32, 16);
    memcpy (s3, in + 48, 16);

    AES4 (0);
    MIX4;
    AES4 (8);
    MIX4;
    AES4 (16);
    MIX4;
    AES4 (24);
    MIX4;
    AES4 (32);
    MIX4;
    AES4 (40);
    MIX4;

    for (i = 0; i < 16; ++i) {
        s0[i] = in[i] ^ s0[i];
        s1[i] = in[i + 16] ^ s1[i];
        s2[i] = in[i + 32] ^ s2[i];
        s3[i] = in[i + 48] ^ s3[i];
    }

    ((uint64_t *)out)[0] = ((uint64_t *)s0)[1];
    ((uint64_t *)out)[1] = ((uint64_t *)s1)[1];
    ((uint64_t *)out)[2] = ((uint64_t *)s2)[0];
    ((uint64_t *)out)[3] = ((uint64_t *)s3)[0];
}