K_1 = k_255||...||k_224;
K_2 = k_223||...||k_192;
K_3 = k_191||...||k_160;
K_4 = k_159||...||k_128;
K_5 = k_127||...||k_96;
K_6 = k_95||...||k_64;
K_7 = k_63||...||k_32;
K_8 = k_31||...||k_0;
K_(i+8) = K_i, i = 1, 2, ..., 8;
K_(i+16) = K_i, i = 1, 2, ..., 8;
K_(i+24) = K_(9-i), i = 1, 2, ..., 8.