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 */
}
/*
* State machine for state 3, Connected State.
* The handling of the timer(s) is in file ax25_timer.c
* Handling of state 0 and connection release is in ax25.c.
*/
static int ax25_ds_state3_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_start_t3timer(ax25);
ax25_start_idletimer(ax25);
ax25->condition = 0x00;
ax25->vs = 0;
ax25->va = 0;
ax25->vr = 0;
ax25_requeue_frames(ax25);
ax25_dama_on(ax25);
break;
case AX25_DISC:
ax25_send_control(ax25, AX25_UA, pf, AX25_RESPONSE);
ax25_dama_off(ax25);
ax25_disconnect(ax25, 0);
break;
case AX25_DM:
ax25_dama_off(ax25);
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 (ax25_validate_nr(ax25, nr)) {
if (ax25_check_iframes_acked(ax25, nr))
ax25->n2count=0;
if (type == AX25_COMMAND && pf)
ax25_ds_enquiry_response(ax25);
} else {
ax25_ds_nr_error_recovery(ax25);
ax25->state = AX25_STATE_1;
}
break;
case AX25_REJ:
ax25->condition &= ~AX25_COND_PEER_RX_BUSY;
if (ax25_validate_nr(ax25, nr)) {
if (ax25->va != nr)
ax25->n2count=0;
ax25_frames_acked(ax25, nr);
ax25_calculate_rtt(ax25);
ax25_stop_t1timer(ax25);
ax25_start_t3timer(ax25);
ax25_requeue_frames(ax25);
if (type == AX25_COMMAND && pf)
ax25_ds_enquiry_response(ax25);
} else {
ax25_ds_nr_error_recovery(ax25);
ax25->state = AX25_STATE_1;
}
break;
case AX25_I:
if (!ax25_validate_nr(ax25, nr)) {
ax25_ds_nr_error_recovery(ax25);
ax25->state = AX25_STATE_1;
break;
}
if (ax25->condition & AX25_COND_PEER_RX_BUSY) {
ax25_frames_acked(ax25, nr);
ax25->n2count = 0;
} else {
if (ax25_check_iframes_acked(ax25, nr))
ax25->n2count = 0;
}
if (ax25->condition & AX25_COND_OWN_RX_BUSY) {
if (pf) ax25_ds_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_ds_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_ds_enquiry_response(ax25);
} else {
ax25->condition |= AX25_COND_REJECT;
ax25_ds_enquiry_response(ax25);
ax25->condition &= ~AX25_COND_ACK_PENDING;
}
}
break;
case AX25_FRMR:
case AX25_ILLEGAL:
ax25_ds_establish_data_link(ax25);
ax25->state = AX25_STATE_1;
break;
default:
break;
}
return queued;
}
