BF_DECRYPT
BF_ecb_encrypt(out, out, &key, BF_DECRYPT);
BF_cbc_encrypt(cbc_out, cbc_in, len, &key, iv, BF_DECRYPT);
BF_cfb64_encrypt(cbc_out, cbc_in, 17, &key, iv, &n, BF_DECRYPT);
&key, iv, &n, BF_DECRYPT);