Example #1
0
/*
 *	State machine for state 1, Awaiting Connection State.
 *	The handling of the timer(s) is in file ax25_ds_timer.c.
 *	Handling of state 0 and connection release is in ax25.c.
 */
static int ax25_ds_state1_machine(ax25_cb *ax25, struct sk_buff *skb, int frametype, int pf, int type)
{
    switch (frametype) {
    case AX25_SABM:
        ax25->modulus = AX25_MODULUS;
        ax25->window  = ax25->ax25_dev->values[AX25_VALUES_WINDOW];
        ax25_send_control(ax25, AX25_UA, pf, AX25_RESPONSE);
        break;

    case AX25_SABME:
        ax25->modulus = AX25_EMODULUS;
        ax25->window  =  ax25->ax25_dev->values[AX25_VALUES_EWINDOW];
        ax25_send_control(ax25, AX25_UA, pf, AX25_RESPONSE);
        break;

    case AX25_DISC:
        ax25_send_control(ax25, AX25_DM, pf, AX25_RESPONSE);
        break;

    case AX25_UA:
        ax25_calculate_rtt(ax25);
        ax25_stop_t1timer(ax25);
        ax25_start_t3timer(ax25);
        ax25_start_idletimer(ax25);
        ax25->vs      = 0;
        ax25->va      = 0;
        ax25->vr      = 0;
        ax25->state   = AX25_STATE_3;
        ax25->n2count = 0;
        if (ax25->sk != NULL) {
            ax25->sk->state = TCP_ESTABLISHED;
            /* For WAIT_SABM connections we will produce an accept ready socket here */
            if (!ax25->sk->dead)
                ax25->sk->state_change(ax25->sk);
        }
        ax25_dama_on(ax25);

        /* according to DK4EG´s spec we are required to
         * send a RR RESPONSE FINAL NR=0. Please mail
         * <*****@*****.**> if this causes problems
         * with the TheNetNode DAMA Master implementation.
         */

        ax25_std_enquiry_response(ax25);
        break;

    case AX25_DM:
        if (pf) ax25_disconnect(ax25, ECONNREFUSED);
        break;

    default:
        if (pf) ax25_send_control(ax25, AX25_SABM, AX25_POLLON, AX25_COMMAND);
        break;
    }

    return 0;
}
Example #2
0
/*
 *	State machine for state 4, Timer Recovery State.
 *	The handling of the timer(s) is in file ax25_std_timer.c
 *	Handling of state 0 and connection release is in ax25.c.
 */
static int ax25_std_state4_machine(ax25_cb *ax25, struct sk_buff *skb, int frametype, int ns, int nr, int pf, int type)
{
	int queued = 0;

	switch (frametype) {
	case AX25_SABM:
	case AX25_SABME:
		if (frametype == AX25_SABM) {
			ax25->modulus = AX25_MODULUS;
			ax25->window  = ax25->ax25_dev->values[AX25_VALUES_WINDOW];
		} else {
			ax25->modulus = AX25_EMODULUS;
			ax25->window  = ax25->ax25_dev->values[AX25_VALUES_EWINDOW];
		}
		ax25_send_control(ax25, AX25_UA, pf, AX25_RESPONSE);
		ax25_stop_t1timer(ax25);
		ax25_stop_t2timer(ax25);
		ax25_start_t3timer(ax25);
		ax25_start_idletimer(ax25);
		ax25->condition = 0x00;
		ax25->vs        = 0;
		ax25->va        = 0;
		ax25->vr        = 0;
		ax25->state     = AX25_STATE_3;
		ax25->n2count   = 0;
		ax25_requeue_frames(ax25);
		break;

	case AX25_DISC:
		ax25_send_control(ax25, AX25_UA, pf, AX25_RESPONSE);
		ax25_disconnect(ax25, 0);
		break;

	case AX25_DM:
		ax25_disconnect(ax25, ECONNRESET);
		break;

	case AX25_RR:
	case AX25_RNR:
		if (frametype == AX25_RR)
			ax25->condition &= ~AX25_COND_PEER_RX_BUSY;
		else
			ax25->condition |= AX25_COND_PEER_RX_BUSY;
		if (type == AX25_RESPONSE && pf) {
			ax25_stop_t1timer(ax25);
			ax25->n2count = 0;
			if (ax25_validate_nr(ax25, nr)) {
				ax25_frames_acked(ax25, nr);
				if (ax25->vs == ax25->va) {
					ax25_start_t3timer(ax25);
					ax25->state   = AX25_STATE_3;
				} else {
					ax25_requeue_frames(ax25);
				}
			} else {
				ax25_std_nr_error_recovery(ax25);
				ax25->state = AX25_STATE_1;
			}
			break;
		}
		if (type == AX25_COMMAND && pf)
			ax25_std_enquiry_response(ax25);
		if (ax25_validate_nr(ax25, nr)) {
			ax25_frames_acked(ax25, nr);
		} else {
			ax25_std_nr_error_recovery(ax25);
			ax25->state = AX25_STATE_1;
		}
		break;

	case AX25_REJ:
		ax25->condition &= ~AX25_COND_PEER_RX_BUSY;
		if (pf && type == AX25_RESPONSE) {
			ax25_stop_t1timer(ax25);
			ax25->n2count = 0;
			if (ax25_validate_nr(ax25, nr)) {
				ax25_frames_acked(ax25, nr);
				if (ax25->vs == ax25->va) {
					ax25_start_t3timer(ax25);
					ax25->state   = AX25_STATE_3;
				} else {
					ax25_requeue_frames(ax25);
				}
			} else {
				ax25_std_nr_error_recovery(ax25);
				ax25->state = AX25_STATE_1;
			}
			break;
		}
		if (type == AX25_COMMAND && pf)
			ax25_std_enquiry_response(ax25);
		if (ax25_validate_nr(ax25, nr)) {
			ax25_frames_acked(ax25, nr);
			ax25_requeue_frames(ax25);
		} else {
			ax25_std_nr_error_recovery(ax25);
			ax25->state = AX25_STATE_1;
		}
		break;

	case AX25_I:
		if (!ax25_validate_nr(ax25, nr)) {
			ax25_std_nr_error_recovery(ax25);
			ax25->state = AX25_STATE_1;
			break;
		}
		ax25_frames_acked(ax25, nr);
		if (ax25->condition & AX25_COND_OWN_RX_BUSY) {
			if (pf)
				ax25_std_enquiry_response(ax25);
			break;
		}
		if (ns == ax25->vr) {
			ax25->vr = (ax25->vr + 1) % ax25->modulus;
			queued = ax25_rx_iframe(ax25, skb);
			if (ax25->condition & AX25_COND_OWN_RX_BUSY)
				ax25->vr = ns;	/* ax25->vr - 1 */
			ax25->condition &= ~AX25_COND_REJECT;
			if (pf) {
				ax25_std_enquiry_response(ax25);
			} else {
				if (!(ax25->condition & AX25_COND_ACK_PENDING)) {
					ax25->condition |= AX25_COND_ACK_PENDING;
					ax25_start_t2timer(ax25);
				}
			}
		} else {
			if (ax25->condition & AX25_COND_REJECT) {
				if (pf) ax25_std_enquiry_response(ax25);
			} else {
				ax25->condition |= AX25_COND_REJECT;
				ax25_send_control(ax25, AX25_REJ, pf, AX25_RESPONSE);
				ax25->condition &= ~AX25_COND_ACK_PENDING;
			}
		}
		break;

	case AX25_FRMR:
	case AX25_ILLEGAL:
		ax25_std_establish_data_link(ax25);
		ax25->state = AX25_STATE_1;
		break;

	default:
		break;
	}

	return queued;
}
/*
 *	State machine for state 1, Awaiting Connection State.
 *	The handling of the timer(s) is in file ax25_ds_timer.c.
 *	Handling of state 0 and connection release is in ax25.c.
 */
static int ax25_ds_state1_machine(ax25_cb *ax25, struct sk_buff *skb, int frametype, int pf, int type)
{
	switch (frametype) {
	case AX25_SABM:
		ax25->modulus = AX25_MODULUS;
		ax25->window  = ax25->ax25_dev->values[AX25_VALUES_WINDOW];
		ax25_send_control(ax25, AX25_UA, pf, AX25_RESPONSE);
		break;

	case AX25_SABME:
		ax25->modulus = AX25_EMODULUS;
		ax25->window  =  ax25->ax25_dev->values[AX25_VALUES_EWINDOW];
		ax25_send_control(ax25, AX25_UA, pf, AX25_RESPONSE);
		break;

	case AX25_DISC:
		ax25_send_control(ax25, AX25_DM, pf, AX25_RESPONSE);
		break;

	case AX25_UA:
		ax25_calculate_rtt(ax25);
		ax25_stop_t1timer(ax25);
		ax25_start_t3timer(ax25);
		ax25_start_idletimer(ax25);
		ax25->vs      = 0;
		ax25->va      = 0;
		ax25->vr      = 0;
		ax25->state   = AX25_STATE_3;
		ax25->n2count = 0;
		if (ax25->sk != NULL) {
			bh_lock_sock(ax25->sk);
			ax25->sk->sk_state = TCP_ESTABLISHED;
			/*
			 * For WAIT_SABM connections we will produce an accept
			 * ready socket here
			 */
			if (!sock_flag(ax25->sk, SOCK_DEAD))
				ax25->sk->sk_state_change(ax25->sk);
			bh_unlock_sock(ax25->sk);
		}
		ax25_dama_on(ax25);

		/* according to DK4EG's spec we are required to
		 * send a RR RESPONSE FINAL NR=0.
		 */

		ax25_std_enquiry_response(ax25);
		break;

	case AX25_DM:
		if (pf)
			ax25_disconnect(ax25, ECONNREFUSED);
		break;

	default:
		if (pf)
			ax25_send_control(ax25, AX25_SABM, AX25_POLLON, AX25_COMMAND);
		break;
	}

	return 0;
}