/*
* State machine for state 1, Awaiting Connection 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_state1_machine(ax25_cb *ax25, struct sk_buff *skb, int frametype, int pf, int type, int dama)
{
switch (frametype) {
case AX25_SABM:
ax25->modulus = AX25_MODULUS;
ax25->window = ax25_dev_get_value(ax25->device, AX25_VALUES_WINDOW);
ax25_send_control(ax25, AX25_UA, pf, AX25_RESPONSE);
break;
case AX25_SABME:
ax25->modulus = AX25_EMODULUS;
ax25->window = ax25_dev_get_value(ax25->device, 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:
if (pf || dama) {
if (dama) ax25_dama_on(ax25); /* bke */
ax25_calculate_rtt(ax25);
ax25->t1timer = 0;
ax25->t3timer = ax25->t3;
ax25->idletimer = ax25->idle;
ax25->vs = 0;
ax25->va = 0;
ax25->vr = 0;
ax25->state = AX25_STATE_3;
ax25->n2count = 0;
ax25->dama_slave = dama; /* bke */
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);
}
}
break;
case AX25_DM:
if (pf) {
if (ax25->modulus == AX25_MODULUS) {
ax25_disconnect(ax25, ECONNREFUSED);
} else {
ax25->modulus = AX25_MODULUS;
ax25->window = ax25_dev_get_value(ax25->device, AX25_VALUES_WINDOW);
}
}
break;
default:
if (dama && pf)
ax25_send_control(ax25, AX25_SABM, AX25_POLLON, AX25_COMMAND);
break;
}
return 0;
}
/* dl1bke 960114: The DAMA protocol requires to send data and SABM/DISC
* within the poll of any connected channel. Remember
* that we are not allowed to send anything unless we
* get polled by the Master.
*
* Thus we'll have to do parts of our T1 handling in
* ax25_enquiry_response().
*/
void ax25_t1_timeout(ax25_cb *ax25)
{
switch (ax25->state) {
case AX25_STATE_1:
if (ax25->n2count == ax25->n2) {
if (ax25->modulus == AX25_MODULUS) {
ax25_disconnect(ax25, ETIMEDOUT);
} else {
ax25->modulus = AX25_MODULUS;
ax25->window = ax25_dev_get_value(ax25->device, AX25_VALUES_WINDOW);
ax25->n2count = 0;
ax25_send_control(ax25, AX25_SABM, ax25_dev_is_dama_slave(ax25->device) ? AX25_POLLOFF : AX25_POLLON, AX25_COMMAND);
}
} else {
ax25->n2count++;
if (ax25->modulus == AX25_MODULUS)
ax25_send_control(ax25, AX25_SABM, ax25_dev_is_dama_slave(ax25->device) ? AX25_POLLOFF : AX25_POLLON, AX25_COMMAND);
else
ax25_send_control(ax25, AX25_SABME, ax25_dev_is_dama_slave(ax25->device) ? AX25_POLLOFF : AX25_POLLON, AX25_COMMAND);
}
break;
case AX25_STATE_2:
if (ax25->n2count == ax25->n2) {
ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
ax25_disconnect(ax25, ETIMEDOUT);
} else {
ax25->n2count++;
if (!ax25_dev_is_dama_slave(ax25->device))
ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
}
break;
case AX25_STATE_3:
ax25->n2count = 1;
if (!ax25->dama_slave)
ax25_transmit_enquiry(ax25);
ax25->state = AX25_STATE_4;
break;
case AX25_STATE_4:
if (ax25->n2count == ax25->n2) {
ax25_send_control(ax25, AX25_DM, AX25_POLLON, AX25_RESPONSE);
ax25_disconnect(ax25, ETIMEDOUT);
} else {
ax25->n2count++;
if (!ax25->dama_slave)
ax25_transmit_enquiry(ax25);
}
break;
}
ax25->t1timer = ax25->t1 = ax25_calculate_t1(ax25);
ax25_set_timer(ax25);
}
/*
* This is where all valid I frames are sent to, to be dispatched to
* whichever protocol requires them.
*/
static int ax25_rx_iframe(ax25_cb *ax25, struct sk_buff *skb)
{
int (*func)(struct sk_buff *, ax25_cb *);
struct sk_buff *skbn;
volatile int queued = 0;
unsigned char pid;
if (skb == NULL) return 0;
ax25->idletimer = ax25->idle;
pid = *skb->data;
#ifdef CONFIG_INET
if (pid == AX25_P_IP) {
if ((skbn = skb_copy(skb, GFP_ATOMIC)) != NULL) {
kfree_skb(skb, FREE_READ);
skb = skbn;
}
skb_pull(skb, 1); /* Remove PID */
skb->h.raw = skb->data;
ip_rcv(skb, ax25->device, NULL); /* Wrong ptype */
return 1;
}
#endif
if (pid == AX25_P_SEGMENT) {
skb_pull(skb, 1); /* Remove PID */
return ax25_rx_fragment(ax25, skb);
}
if ((func = ax25_protocol_function(pid)) != NULL) {
skb_pull(skb, 1); /* Remove PID */
return (*func)(skb, ax25);
}
if (ax25->sk != NULL && ax25_dev_get_value(ax25->device, AX25_VALUES_CONMODE) == 2) {
if ((!ax25->pidincl && ax25->sk->protocol == pid) || ax25->pidincl) {
if (sock_queue_rcv_skb(ax25->sk, skb) == 0)
queued = 1;
else
ax25->condition |= AX25_COND_OWN_RX_BUSY;
}
}
return queued;
}
/* dl1bke 960114: The DAMA protocol requires to send data and SABM/DISC
* within the poll of any connected channel. Remember
* that we are not allowed to send anything unless we
* get polled by the Master.
*
* Thus we'll have to do parts of our T1 handling in
* ax25_enquiry_response().
*/
void ax25_t1_timeout(ax25_cb * ax25)
{
switch (ax25->state) {
case AX25_STATE_1:
if (ax25->n2count == ax25->n2) {
if (ax25->modulus == MODULUS) {
#ifdef CONFIG_NETROM
nr_link_failed(&ax25->dest_addr, ax25->device);
#endif
ax25_clear_queues(ax25);
ax25->state = AX25_STATE_0;
if (ax25->sk != NULL) {
ax25->sk->state = TCP_CLOSE;
ax25->sk->err = ETIMEDOUT;
if (!ax25->sk->dead)
ax25->sk->state_change(ax25->sk);
ax25->sk->dead = 1;
}
} else {
ax25->modulus = MODULUS;
ax25->window = ax25_dev_get_value(ax25->device, AX25_VALUES_WINDOW);
ax25->n2count = 0;
ax25_send_control(ax25, SABM, ax25_dev_is_dama_slave(ax25->device)? POLLOFF : POLLON, C_COMMAND);
}
} else {
ax25->n2count++;
if (ax25->modulus == MODULUS) {
ax25_send_control(ax25, SABM, ax25_dev_is_dama_slave(ax25->device)? POLLOFF : POLLON, C_COMMAND);
} else {
ax25_send_control(ax25, SABME, ax25_dev_is_dama_slave(ax25->device)? POLLOFF : POLLON, C_COMMAND);
}
}
break;
case AX25_STATE_2:
if (ax25->n2count == ax25->n2) {
#ifdef CONFIG_NETROM
nr_link_failed(&ax25->dest_addr, ax25->device);
#endif
ax25_clear_queues(ax25);
ax25->state = AX25_STATE_0;
ax25_send_control(ax25, DISC, POLLON, C_COMMAND);
if (ax25->sk != NULL) {
ax25->sk->state = TCP_CLOSE;
ax25->sk->err = ETIMEDOUT;
if (!ax25->sk->dead)
ax25->sk->state_change(ax25->sk);
ax25->sk->dead = 1;
}
} else {
ax25->n2count++;
if (!ax25_dev_is_dama_slave(ax25->device))
ax25_send_control(ax25, DISC, POLLON, C_COMMAND);
}
break;
case AX25_STATE_3:
ax25->n2count = 1;
if (!ax25->dama_slave)
ax25_transmit_enquiry(ax25);
ax25->state = AX25_STATE_4;
break;
case AX25_STATE_4:
if (ax25->n2count == ax25->n2) {
#ifdef CONFIG_NETROM
nr_link_failed(&ax25->dest_addr, ax25->device);
#endif
ax25_clear_queues(ax25);
ax25_send_control(ax25, DM, POLLON, C_RESPONSE);
ax25->state = AX25_STATE_0;
if (ax25->sk != NULL) {
if (ax25->sk->debug)
printk("Link Failure\n");
ax25->sk->state = TCP_CLOSE;
ax25->sk->err = ETIMEDOUT;
if (!ax25->sk->dead)
ax25->sk->state_change(ax25->sk);
ax25->sk->dead = 1;
}
} else {
ax25->n2count++;
if (!ax25->dama_slave)
ax25_transmit_enquiry(ax25);
}
break;
}
ax25->t1timer = ax25->t1 = ax25_calculate_t1(ax25);
ax25_set_timer(ax25);
}
/*
* State machine for state 4, Timer Recovery 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_state4_machine(ax25_cb *ax25, struct sk_buff *skb, int frametype, int ns, int nr, int pf, int type, int dama)
{
int queued = 0;
switch (frametype) {
case AX25_SABM:
case AX25_SABME:
if (dama) ax25_dama_on(ax25);
if (frametype == AX25_SABM) {
ax25->modulus = AX25_MODULUS;
ax25->window = ax25_dev_get_value(ax25->device, AX25_VALUES_WINDOW);
} else {
ax25->modulus = AX25_EMODULUS;
ax25->window = ax25_dev_get_value(ax25->device, AX25_VALUES_EWINDOW);
}
ax25_send_control(ax25, AX25_UA, pf, AX25_RESPONSE);
ax25->condition = 0x00;
ax25->t1timer = 0;
ax25->t3timer = ax25->t3;
ax25->idletimer = ax25->idle;
ax25->vs = 0;
ax25->va = 0;
ax25->vr = 0;
ax25->state = AX25_STATE_3;
ax25->n2count = 0;
ax25->dama_slave = dama;
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->t1timer = 0;
if (ax25_validate_nr(ax25, nr)) {
ax25_frames_acked(ax25, nr);
if (ax25->vs == ax25->va) {
ax25->t3timer = ax25->t3;
ax25->n2count = 0;
ax25->state = AX25_STATE_3;
} else {
ax25_requeue_frames(ax25);
}
} else {
ax25_nr_error_recovery(ax25);
ax25->state = AX25_STATE_1;
}
break;
}
if (!ax25->dama_slave && type == AX25_COMMAND && pf)
ax25_enquiry_response(ax25);
if (ax25_validate_nr(ax25, nr)) {
ax25_frames_acked(ax25, nr);
if (ax25->dama_slave && type == AX25_COMMAND && pf)
dama_enquiry_response(ax25);
} else {
ax25_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->dama_slave && type == AX25_COMMAND))) {
ax25->t1timer = 0;
if (ax25_validate_nr(ax25, nr)) {
ax25_frames_acked(ax25, nr);
if (ax25->vs == ax25->va) {
ax25->t3timer = ax25->t3;
ax25->n2count = 0;
ax25->state = AX25_STATE_3;
} else {
ax25_requeue_frames(ax25);
}
if (ax25->dama_slave && type == AX25_COMMAND && pf)
dama_enquiry_response(ax25);
} else {
ax25_nr_error_recovery(ax25);
ax25->state = AX25_STATE_1;
}
break;
}
if (!ax25->dama_slave && type == AX25_COMMAND && pf)
ax25_enquiry_response(ax25);
if (ax25_validate_nr(ax25, nr)) {
ax25_frames_acked(ax25, nr);
ax25_requeue_frames(ax25);
if (ax25->dama_slave && type == AX25_COMMAND && pf)
dama_enquiry_response(ax25);
} else {
ax25_nr_error_recovery(ax25);
ax25->state = AX25_STATE_1;
}
break;
case AX25_I:
if (!ax25_validate_nr(ax25, nr)) {
ax25_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) {
if (ax25->dama_slave)
ax25_enquiry_response(ax25);
else
dama_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) {
if (ax25->dama_slave)
dama_enquiry_response(ax25);
else
ax25_enquiry_response(ax25);
} else {
if (!(ax25->condition & AX25_COND_ACK_PENDING)) {
ax25->t2timer = ax25->t2;
ax25->condition |= AX25_COND_ACK_PENDING;
}
}
} else {
if (ax25->condition & AX25_COND_REJECT) {
if (pf) {
if (ax25->dama_slave)
dama_enquiry_response(ax25);
else
ax25_enquiry_response(ax25);
}
} else {
ax25->condition |= AX25_COND_REJECT;
if (ax25->dama_slave)
dama_enquiry_response(ax25);
else
ax25_send_control(ax25, AX25_REJ, pf, AX25_RESPONSE);
ax25->condition &= ~AX25_COND_ACK_PENDING;
}
}
break;
case AX25_FRMR:
case AX25_ILLEGAL:
ax25_establish_data_link(ax25);
ax25->state = AX25_STATE_1;
break;
default:
break;
}
return queued;
}