예제 #1
0
void ax25_std_nr_error_recovery(ax25_cb *ax25)
{
	ax25_std_establish_data_link(ax25);
}
예제 #2
0
ax25_cb *ax25_send_frame(struct sk_buff *skb, int paclen, ax25_address *src, ax25_address *dest, ax25_digi *digi, struct net_device *dev)
{
	ax25_dev *ax25_dev;
	ax25_cb *ax25;

	/*
	 * Take the default packet length for the device if zero is
	 * specified.
	 */
	if (paclen == 0) {
		if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL)
			return NULL;

		paclen = ax25_dev->values[AX25_VALUES_PACLEN];
	}

	/*
	 * Look for an existing connection.
	 */
	if ((ax25 = ax25_find_cb(src, dest, digi, dev)) != NULL) {
		ax25_output(ax25, paclen, skb);
		return ax25;		/* It already existed */
	}

	if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL)
		return NULL;

	if ((ax25 = ax25_create_cb()) == NULL)
		return NULL;

	ax25_fillin_cb(ax25, ax25_dev);

	ax25->source_addr = *src;
	ax25->dest_addr   = *dest;

	if (digi != NULL) {
		ax25->digipeat = kmemdup(digi, sizeof(*digi), GFP_ATOMIC);
		if (ax25->digipeat == NULL) {
			ax25_cb_put(ax25);
			return NULL;
		}
	}

	switch (ax25->ax25_dev->values[AX25_VALUES_PROTOCOL]) {
	case AX25_PROTO_STD_SIMPLEX:
	case AX25_PROTO_STD_DUPLEX:
		ax25_std_establish_data_link(ax25);
		break;

#ifdef CONFIG_AX25_DAMA_SLAVE
	case AX25_PROTO_DAMA_SLAVE:
		if (ax25_dev->dama.slave)
			ax25_ds_establish_data_link(ax25);
		else
			ax25_std_establish_data_link(ax25);
		break;
#endif
	}

	/*
	 * There is one ref for the state machine; a caller needs
	 * one more to put it back, just like with the existing one.
	 */
	ax25_cb_hold(ax25);

	ax25_cb_add(ax25);

	ax25->state = AX25_STATE_1;

	ax25_start_heartbeat(ax25);

	ax25_output(ax25, paclen, skb);

	return ax25;			/* We had to create it */
}
예제 #3
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;
}