aescrypp.c

Arithmetic for integers of almost rijndael for C and C++. Developed for linux

    : s(x,0))       \
 : r==2 ?           \
    ( c==0 ? nc==8 ? s(x,3) : s(x,2) \
    : c==1 ? nc==8 ? s(x,4) : s(x,3) \
    : c==2 ? nc==8 ? s(x,5) : nc==4 ? s(x,0) : s(x,4) \
    : c==3 ? nc==8 ? s(x,6) : nc==5 ? s(x,0) : nc==4 ? s(x,1) : s(x,5) \
    : c==4 ? nc==8 ? s(x,7) : nc==7 ? s(x,6) : nc==6 ? s(x,0) : s(x,1) \
    : c==5 ? nc==6 ? s(x,1) : s(x,0) \
    : c==6 ? s(x,1) \
    : s(x,2))       \
 :                  \
    ( c==0 ? nc>6  ? s(x,4) : s(x,3) \
    : c==1 ? nc>6  ? s(x,5) : nc==4 ? s(x,0) : s(x,4) \
    : c==2 ? nc>6  ? s(x,6) : nc==6 ? s(x,5) : nc==5 ? s(x,0) : s(x,1) \
    : c==3 ? nc==8 ? s(x,7) : nc==5 ? s(x,1) : nc==4 ? s(x,2) : s(x,0) \
    : c==4 ? nc==8 ? s(x,0) : nc==5 ? s(x,2) : s(x,1) \
    : c==5 ? nc==8 ? s(x,1) : s(x,2) \
    : c==6 ? nc==8 ? s(x,2) : s(x,3) \
    : s(x,3)))

#if defined(FT4_SET)
#undef  dec_fmvars
#define dec_fmvars
#define fwd_rnd(y,x,k,c)    s(y,c)= (k)[c] ^ four_tables(x,ft_tab,fwd_var,rf1,c)
#elif defined(FT1_SET)
#undef  dec_fmvars
#define dec_fmvars
#define fwd_rnd(y,x,k,c)    s(y,c)= (k)[c] ^ one_table(x,upr,ft_tab,fwd_var,rf1,c)
#else
#define fwd_rnd(y,x,k,c)    s(y,c) = fwd_mcol(no_table(x,s_box,fwd_var,rf1,c)) ^ (k)[c]
#endif

#if defined(FL4_SET)
#define fwd_lrnd(y,x,k,c)   s(y,c)= (k)[c] ^ four_tables(x,fl_tab,fwd_var,rf1,c)
#elif defined(FL1_SET)
#define fwd_lrnd(y,x,k,c)   s(y,c)= (k)[c] ^ one_table(x,ups,fl_tab,fwd_var,rf1,c)
#else
#define fwd_lrnd(y,x,k,c)   s(y,c) = no_table(x,s_box,fwd_var,rf1,c) ^ (k)[c]
#endif

aes_rval aes_enc_blk(const unsigned char in_blk[], unsigned char out_blk[], const aes_ctx cx[1])
{   uint32_t        locals(b0, b1);
    const uint32_t  *kp = cx->k_sch;
    dec_fmvars  /* declare variables for fwd_mcol() if needed */

    if(!(cx->n_blk & 1)) return aes_bad;

#if (ENC_UNROLL == FULL)

    state_in((cx->n_rnd & 1 ? b1 : b0), in_blk, kp); 
    kp += (cx->n_rnd - 9) * nc;

    switch(cx->n_rnd)
    {
    case 14:    round(fwd_rnd,  b1, b0, kp - 4 * nc);
    case 13:    round(fwd_rnd,  b0, b1, kp - 3 * nc);
    case 12:    round(fwd_rnd,  b1, b0, kp - 2 * nc);
    case 11:    round(fwd_rnd,  b0, b1, kp -     nc);
    case 10:    round(fwd_rnd,  b1, b0, kp         );             
                round(fwd_rnd,  b0, b1, kp +     nc);
                round(fwd_rnd,  b1, b0, kp + 2 * nc); 
                round(fwd_rnd,  b0, b1, kp + 3 * nc);
                round(fwd_rnd,  b1, b0, kp + 4 * nc); 
                round(fwd_rnd,  b0, b1, kp + 5 * nc);
                round(fwd_rnd,  b1, b0, kp + 6 * nc); 
                round(fwd_rnd,  b0, b1, kp + 7 * nc);
                round(fwd_rnd,  b1, b0, kp + 8 * nc);
                round(fwd_lrnd, b0, b1, kp + 9 * nc);
    }
#else
    {   uint32_t    rnd;

        state_in(b0, in_blk, kp); 

#if (ENC_UNROLL == PARTIAL)

        for(rnd = 0; rnd < (cx->n_rnd - 1) >> 1; ++rnd)
        {
            kp += nc;
            round(fwd_rnd, b1, b0, kp); 
            kp += nc;
            round(fwd_rnd, b0, b1, kp); 
        }

        if(cx->n_rnd & 1) 
        {
            l_copy(b1, b0);
        }
        else
        {
            kp += nc;
            round(fwd_rnd,  b1, b0, kp); 
        }
#else
        for(rnd = 0; rnd < cx->n_rnd - 1; ++rnd)
        {
            kp += nc;
            round(fwd_rnd, b1, b0, kp); 
            l_copy(b0, b1); 
        }
#endif
        kp += nc;
        round(fwd_lrnd, b0, b1, kp);
    }
#endif

    state_out(out_blk, b0);
    return aes_good;
}

#endif

#if defined(DECRYPTION)

#define inv_var(x,r,c) \
 ( r==0 ?           \
    ( c==0 ? s(x,0) \
    : c==1 ? s(x,1) \
    : c==2 ? s(x,2) \
    : c==3 ? s(x,3) \
    : c==4 ? s(x,4) \
    : c==5 ? s(x,5) \
    : c==6 ? s(x,6) \
    : s(x,7))       \
 : r==1 ?           \
    ( c==0 ? nc==8 ? s(x,7) : nc==7 ? s(x,6) : nc==6 ? s(x,5) : nc==5 ? s(x,4) : s(x,3) \
    : c==1 ? s(x,0) \
    : c==2 ? s(x,1) \
    : c==3 ? s(x,2) \
    : c==4 ? s(x,3) \
    : c==5 ? s(x,4) \
    : c==6 ? s(x,5) \
    : s(x,6))       \
 : r==2 ?           \
    ( c==0 ? nc>6  ? s(x,5) : nc==6 ? s(x,4) : nc==5 ? s(x,3) : s(x,2) \
    : c==1 ? nc>6  ? s(x,6) : nc==6 ? s(x,5) : nc==5 ? s(x,4) : s(x,3) \
    : c==2 ? nc==8 ? s(x,7) : s(x,0) \
    : c==3 ? nc==8 ? s(x,0) : s(x,1) \
    : c==4 ? nc==8 ? s(x,1) : s(x,2) \
    : c==5 ? nc==8 ? s(x,2) : s(x,3) \
    : c==6 ? nc==8 ? s(x,3) : s(x,4) \
    : s(x,4))       \
 :                  \
    ( c==0 ? nc==8 ? s(x,4) : nc==5 ? s(x,2) : nc==4 ? s(x,1) : s(x,3) \
    : c==1 ? nc==8 ? s(x,5) : nc==5 ? s(x,3) : nc==4 ? s(x,2) : s(x,4) \
    : c==2 ? nc==8 ? s(x,6) : nc==5 ? s(x,4) : nc==4 ? s(x,3) : s(x,5) \
    : c==3 ? nc==8 ? s(x,7) : nc==7 ? s(x,6) : s(x,0) \
    : c==4 ? nc>6  ? s(x,0) : s(x,1) \
    : c==5 ? nc==6 ? s(x,2) : s(x,1) \
    : c==6 ? s(x,2) \
    : s(x,3)))

#if defined(IT4_SET)
#undef  dec_imvars
#define dec_imvars
#define inv_rnd(y,x,k,c)    s(y,c)= (k)[c] ^ four_tables(x,it_tab,inv_var,rf1,c)
#elif defined(IT1_SET)
#undef  dec_imvars
#define dec_imvars
#define inv_rnd(y,x,k,c)    s(y,c)= (k)[c] ^ one_table(x,upr,it_tab,inv_var,rf1,c)
#else
#define inv_rnd(y,x,k,c)    s(y,c) = inv_mcol(no_table(x,inv_s_box,inv_var,rf1,c) ^ (k)[c])
#endif

#if defined(IL4_SET)
#define inv_lrnd(y,x,k,c)   s(y,c)= (k)[c] ^ four_tables(x,il_tab,inv_var,rf1,c)
#elif defined(IL1_SET)
#define inv_lrnd(y,x,k,c)   s(y,c)= (k)[c] ^ one_table(x,ups,il_tab,inv_var,rf1,c)
#else
#define inv_lrnd(y,x,k,c)   s(y,c) = no_table(x,inv_s_box,inv_var,rf1,c) ^ (k)[c]
#endif

aes_rval aes_dec_blk(const unsigned char in_blk[], unsigned char out_blk[], const aes_ctx cx[1])
{   uint32_t        locals(b0, b1);
    const uint32_t  *kp = cx->k_sch + nc * cx->n_rnd;
    dec_imvars  /* declare variables for inv_mcol() if needed */

    if(!(cx->n_blk & 2)) return aes_bad;

#if (DEC_UNROLL == FULL)

    state_in((cx->n_rnd & 1 ? b1 : b0), in_blk, kp); 
    kp = cx->k_sch + 9 * nc;

    switch(cx->n_rnd)
    {
    case 14:    round(inv_rnd,  b1, b0, kp + 4 * nc);
    case 13:    round(inv_rnd,  b0, b1, kp + 3 * nc);
    case 12:    round(inv_rnd,  b1, b0, kp + 2 * nc);
    case 11:    round(inv_rnd,  b0, b1, kp +     nc);
    case 10:    round(inv_rnd,  b1, b0, kp         );             
                round(inv_rnd,  b0, b1, kp -     nc);
                round(inv_rnd,  b1, b0, kp - 2 * nc); 
                round(inv_rnd,  b0, b1, kp - 3 * nc);
                round(inv_rnd,  b1, b0, kp - 4 * nc); 
                round(inv_rnd,  b0, b1, kp - 5 * nc);
                round(inv_rnd,  b1, b0, kp - 6 * nc); 
                round(inv_rnd,  b0, b1, kp - 7 * nc);
                round(inv_rnd,  b1, b0, kp - 8 * nc);
                round(inv_lrnd, b0, b1, kp - 9 * nc);
    }
#else
    {   uint32_t    rnd;

        state_in(b0, in_blk, kp); 

#if (DEC_UNROLL == PARTIAL)

        for(rnd = 0; rnd < (cx->n_rnd - 1) >> 1; ++rnd)
        {
            kp -= nc;
            round(inv_rnd, b1, b0, kp); 
            kp -= nc;
            round(inv_rnd, b0, b1, kp); 
        }

        if(cx->n_rnd & 1) 
        {
            l_copy(b1, b0);
        }
        else
        {       
            kp -= nc;
            round(inv_rnd,  b1, b0, kp); 
        }
#else
        for(rnd = 0; rnd < cx->n_rnd - 1; ++rnd)
        {
            kp -= nc;
            round(inv_rnd, b1, b0, kp); 
            l_copy(b0, b1); 
        }
#endif
        kp -= nc;
        round(inv_lrnd, b0, b1, kp);
    }
#endif

    state_out(out_blk, b0);
    return aes_good;
}

#endif