int llc_conn_ac_upd_vs(struct sock *sk, struct sk_buff *skb)
{
struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
u8 nr = PDU_SUPV_GET_Nr(pdu);
if (llc_circular_between(llc_sk(sk)->vS, nr, llc_sk(sk)->X))
llc_conn_ac_set_vs_nr(sk, skb);
return 0;
}
/**
* llc_util_nr_inside_tx_window - check if sequence number is in tx window
* @sk: current connection.
* @nr: N(R) of received PDU.
*
* This routine checks if N(R) of received PDU is in range of transmit
* window; on the other hand checks if received PDU acknowledges some
* outstanding PDUs that are in transmit window. Returns 0 for success, 1
* otherwise.
*/
static u16 llc_util_nr_inside_tx_window(struct sock *sk, u8 nr)
{
u8 nr1, nr2;
struct sk_buff *skb;
struct llc_pdu_sn *pdu;
struct llc_opt *llc = llc_sk(sk);
int rc = 0;
if (llc->dev->flags & IFF_LOOPBACK)
goto out;
rc = 1;
if (!skb_queue_len(&llc->pdu_unack_q))
goto out;
skb = skb_peek(&llc->pdu_unack_q);
pdu = llc_pdu_sn_hdr(skb);
nr1 = LLC_I_GET_NS(pdu);
skb = skb_peek_tail(&llc->pdu_unack_q);
pdu = llc_pdu_sn_hdr(skb);
nr2 = LLC_I_GET_NS(pdu);
rc = !llc_circular_between(nr1, nr, (nr2 + 1) % LLC_2_SEQ_NBR_MODULO);
out:
return rc;
}
/**
* llc_util_ns_inside_rx_window - check if sequence number is in rx window
* @ns: sequence number of received pdu.
* @vr: sequence number which receiver expects to receive.
* @rw: receive window size of receiver.
*
* Checks if sequence number of received PDU is in range of receive
* window. Returns 0 for success, 1 otherwise
*/
static u16 llc_util_ns_inside_rx_window(u8 ns, u8 vr, u8 rw)
{
return !llc_circular_between(vr, ns,
(vr + rw - 1) % LLC_2_SEQ_NBR_MODULO);
}
