aes_off
size_t aes_off = 0, blocks;
aes_off += blocks;
memcpy(out + aes_off, in + aes_off,
plen - aes_off);
aesni_cbc_encrypt(out + aes_off, out + aes_off,
len - aes_off, &key->ks, ctx->iv, 1);
aesni_cbc_encrypt(in + aes_off, out + aes_off,
len - aes_off, &key->ks, ctx->iv, 1);