void rijndael::set_key(const u1byte in_key[], const u4byte key_len)
{ u4byte i, t, u, v, w;
if(!tab_gen)
gen_tabs();
k_len = (key_len + 31) / 32;
e_key[0] = u4byte_in(in_key );
e_key[1] = u4byte_in(in_key + 4);
e_key[2] = u4byte_in(in_key + 8);
e_key[3] = u4byte_in(in_key + 12);
switch(k_len)
{
case 4: t = e_key[3];
for(i = 0; i < 10; ++i)
loop4(i);
break;
case 6: e_key[4] = u4byte_in(in_key + 16); t = e_key[5] = u4byte_in(in_key + 20);
for(i = 0; i < 8; ++i)
loop6(i);
break;
case 8: e_key[4] = u4byte_in(in_key + 16); e_key[5] = u4byte_in(in_key + 20);
e_key[6] = u4byte_in(in_key + 24); t = e_key[7] = u4byte_in(in_key + 28);
for(i = 0; i < 7; ++i)
loop8(i);
break;
}
d_key[0] = e_key[0]; d_key[1] = e_key[1];
d_key[2] = e_key[2]; d_key[3] = e_key[3];
for(i = 4; i < 4 * k_len + 24; ++i)
{
imix_col(d_key[i], e_key[i]);
}
return;
}
// encrypt a block of text
#define f_nround(bo, bi, k) \
f_rn(bo, bi, 0, k); \
f_rn(bo, bi, 1, k); \
f_rn(bo, bi, 2, k); \
f_rn(bo, bi, 3, k); \
k += 4
#define f_lround(bo, bi, k) \
f_rl(bo, bi, 0, k); \
f_rl(bo, bi, 1, k); \
f_rl(bo, bi, 2, k); \
f_rl(bo, bi, 3, k)
void rijndael::encrypt(const u1byte in_blk[16], u1byte out_blk[16])
{ u4byte b0[4], b1[4], *kp;
b0[0] = u4byte_in(in_blk ) ^ e_key[0]; b0[1] = u4byte_in(in_blk + 4) ^ e_key[1];
b0[2] = u4byte_in(in_blk + 8) ^ e_key[2]; b0[3] = u4byte_in(in_blk + 12) ^ e_key[3];
kp = e_key + 4;
if(k_len > 6)
{
f_nround(b1, b0, kp); f_nround(b0, b1, kp);
}
if(k_len > 4)
{
f_nround(b1, b0, kp); f_nround(b0, b1, kp);
}
f_nround(b1, b0, kp); f_nround(b0, b1, kp);
f_nround(b1, b0, kp); f_nround(b0, b1, kp);
f_nround(b1, b0, kp); f_nround(b0, b1, kp);
f_nround(b1, b0, kp); f_nround(b0, b1, kp);
f_nround(b1, b0, kp); f_lround(b0, b1, kp);
u4byte_out(out_blk, b0[0]); u4byte_out(out_blk + 4, b0[1]);
u4byte_out(out_blk + 8, b0[2]); u4byte_out(out_blk + 12, b0[3]);
}
// decrypt a block of text
#define i_nround(bo, bi, k) \
i_rn(bo, bi, 0, k); \
i_rn(bo, bi, 1, k); \
i_rn(bo, bi, 2, k); \
i_rn(bo, bi, 3, k); \
k -= 4
#define i_lround(bo, bi, k) \
i_rl(bo, bi, 0, k); \
i_rl(bo, bi, 1, k); \
i_rl(bo, bi, 2, k); \
i_rl(bo, bi, 3, k)
void rijndael::decrypt(const u1byte in_blk[16], u1byte out_blk[16])
{ u4byte b0[4], b1[4], *kp;
b0[0] = u4byte_in(in_blk ) ^ e_key[4 * k_len + 24];
b0[1] = u4byte_in(in_blk + 4) ^ e_key[4 * k_len + 25];
b0[2] = u4byte_in(in_blk + 8) ^ e_key[4 * k_len + 26];
b0[3] = u4byte_in(in_blk + 12) ^ e_key[4 * k_len + 27];
kp = d_key + 4 * (k_len + 5);
if(k_len > 6)
{
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
}
if(k_len > 4)
{
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
}
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
i_nround(b1, b0, kp); i_lround(b0, b1, kp);
u4byte_out(out_blk, b0[0]); u4byte_out(out_blk + 4, b0[1]);
u4byte_out(out_blk + 8, b0[2]); u4byte_out(out_blk + 12, b0[3]);
}
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