static int llc_ui_wait_for_busy_core(struct sock *sk, int timeout)
{
DECLARE_WAITQUEUE(wait, current);
struct llc_sock *llc = llc_sk(sk);
int rc;
add_wait_queue_exclusive(sk->sk_sleep, &wait);
for (;;) {
dprintk("%s: looping...\n", __FUNCTION__);
__set_current_state(TASK_INTERRUPTIBLE);
rc = -ENOTCONN;
if (sk->sk_shutdown & RCV_SHUTDOWN)
break;
rc = 0;
if (llc_data_accept_state(llc->state) || llc->p_flag) {
release_sock(sk);
timeout = schedule_timeout(timeout);
lock_sock(sk);
} else
break;
rc = -ERESTARTSYS;
if (signal_pending(current))
break;
rc = -EAGAIN;
if (!timeout)
break;
}
__set_current_state(TASK_RUNNING);
remove_wait_queue(sk->sk_sleep, &wait);
return rc;
}
/**
* llc_build_and_send_pkt - Connection data sending for upper layers.
* @sk: connection
* @skb: packet to send
*
* This function is called when upper layer wants to send data using
* connection oriented communication mode. During sending data, connection
* will be locked and received frames and expired timers will be queued.
* Returns 0 for success, -ECONNABORTED when the connection already
* closed and -EBUSY when sending data is not permitted in this state or
* LLC has send an I pdu with p bit set to 1 and is waiting for it's
* response.
*/
int llc_build_and_send_pkt(struct sock *sk, struct sk_buff *skb)
{
struct llc_conn_state_ev *ev;
int rc = -ECONNABORTED;
struct llc_opt *llc = llc_sk(sk);
if (llc->state == LLC_CONN_STATE_ADM)
goto out;
rc = -EBUSY;
if (llc_data_accept_state(llc->state)) { /* data_conn_refuse */
llc->failed_data_req = 1;
goto out;
}
if (llc->p_flag) {
llc->failed_data_req = 1;
goto out;
}
ev = llc_conn_ev(skb);
ev->type = LLC_CONN_EV_TYPE_PRIM;
ev->prim = LLC_DATA_PRIM;
ev->prim_type = LLC_PRIM_TYPE_REQ;
skb->dev = llc->dev;
rc = llc_conn_state_process(sk, skb);
out:
return rc;
}
/**
* llc_ui_send_data - send data via reliable llc2 connection
* @sk: Connection the socket is using.
* @skb: Data the user wishes to send.
* @addr: Source and destination fields provided by the user.
* @noblock: can we block waiting for data?
*
* Send data via reliable llc2 connection.
* Returns 0 upon success, non-zero if action did not succeed.
*/
static int llc_ui_send_data(struct sock* sk, struct sk_buff *skb, int noblock)
{
struct llc_sock* llc = llc_sk(sk);
int rc = 0;
if (llc_data_accept_state(llc->state) || llc->p_flag) {
int timeout = sock_sndtimeo(sk, noblock);
rc = llc_ui_wait_for_busy_core(sk, timeout);
}
if (!rc)
rc = llc_build_and_send_pkt(sk, skb);
return rc;
}
/**
* llc_conn_service - finds transition and changes state of connection
* @sk: connection
* @skb: happened event
*
* This function finds transition that matches with happened event, then
* executes related actions and finally changes state of connection.
* Returns 0 for success, 1 for failure.
*/
static int llc_conn_service(struct sock *sk, struct sk_buff *skb)
{
int rc = 1;
struct llc_sock *llc = llc_sk(sk);
struct llc_conn_state_trans *trans;
if (llc->state > NBR_CONN_STATES)
goto out;
rc = 0;
trans = llc_qualify_conn_ev(sk, skb);
if (trans) {
rc = llc_exec_conn_trans_actions(sk, trans, skb);
if (!rc && trans->next_state != NO_STATE_CHANGE) {
llc->state = trans->next_state;
if (!llc_data_accept_state(llc->state))
sk->sk_state_change(sk);
}
}
out:
return rc;
}
/**
* llc_conn_state_process - sends event to connection state machine
* @sk: connection
* @skb: occurred event
*
* Sends an event to connection state machine. After processing event
* (executing it's actions and changing state), upper layer will be
* indicated or confirmed, if needed. Returns 0 for success, 1 for
* failure. The socket lock has to be held before calling this function.
*/
int llc_conn_state_process(struct sock *sk, struct sk_buff *skb)
{
int rc;
struct llc_sock *llc = llc_sk(skb->sk);
struct llc_conn_state_ev *ev = llc_conn_ev(skb);
/*
* We have to hold the skb, because llc_conn_service will kfree it in
* the sending path and we need to look at the skb->cb, where we encode
* llc_conn_state_ev.
*/
skb_get(skb);
ev->ind_prim = ev->cfm_prim = 0;
/*
* Send event to state machine
*/
rc = llc_conn_service(skb->sk, skb);
if (unlikely(rc != 0)) {
;
goto out_kfree_skb;
}
if (unlikely(!ev->ind_prim && !ev->cfm_prim)) {
/* indicate or confirm not required */
if (!skb->next)
goto out_kfree_skb;
goto out_skb_put;
}
if (unlikely(ev->ind_prim && ev->cfm_prim)) /* Paranoia */
skb_get(skb);
switch (ev->ind_prim) {
case LLC_DATA_PRIM:
llc_save_primitive(sk, skb, LLC_DATA_PRIM);
if (unlikely(sock_queue_rcv_skb(sk, skb))) {
/*
* shouldn't happen
*/
// printk(KERN_ERR "%s: sock_queue_rcv_skb failed!\n",
;
kfree_skb(skb);
}
break;
case LLC_CONN_PRIM:
/*
* Can't be sock_queue_rcv_skb, because we have to leave the
* skb->sk pointing to the newly created struct sock in
* llc_conn_handler. -acme
*/
skb_queue_tail(&sk->sk_receive_queue, skb);
sk->sk_state_change(sk);
break;
case LLC_DISC_PRIM:
sock_hold(sk);
if (sk->sk_type == SOCK_STREAM &&
sk->sk_state == TCP_ESTABLISHED) {
sk->sk_shutdown = SHUTDOWN_MASK;
sk->sk_socket->state = SS_UNCONNECTED;
sk->sk_state = TCP_CLOSE;
if (!sock_flag(sk, SOCK_DEAD)) {
sock_set_flag(sk, SOCK_DEAD);
sk->sk_state_change(sk);
}
}
kfree_skb(skb);
sock_put(sk);
break;
case LLC_RESET_PRIM:
/*
* FIXME:
* RESET is not being notified to upper layers for now
*/
;
kfree_skb(skb);
break;
default:
if (ev->ind_prim) {
// printk(KERN_INFO "%s: received unknown %d prim!\n",
;
kfree_skb(skb);
}
/* No indication */
break;
}
switch (ev->cfm_prim) {
case LLC_DATA_PRIM:
if (!llc_data_accept_state(llc->state))
sk->sk_write_space(sk);
else
rc = llc->failed_data_req = 1;
break;
case LLC_CONN_PRIM:
if (sk->sk_type == SOCK_STREAM &&
sk->sk_state == TCP_SYN_SENT) {
if (ev->status) {
sk->sk_socket->state = SS_UNCONNECTED;
sk->sk_state = TCP_CLOSE;
} else {
sk->sk_socket->state = SS_CONNECTED;
sk->sk_state = TCP_ESTABLISHED;
}
sk->sk_state_change(sk);
}
break;
case LLC_DISC_PRIM:
sock_hold(sk);
if (sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_CLOSING) {
sk->sk_socket->state = SS_UNCONNECTED;
sk->sk_state = TCP_CLOSE;
sk->sk_state_change(sk);
}
sock_put(sk);
break;
case LLC_RESET_PRIM:
/*
* FIXME:
* RESET is not being notified to upper layers for now
*/
;
break;
default:
if (ev->cfm_prim) {
// printk(KERN_INFO "%s: received unknown %d prim!\n",
;
break;
}
goto out_skb_put; /* No confirmation */
}
out_kfree_skb:
kfree_skb(skb);
out_skb_put:
kfree_skb(skb);
return rc;
}
int llc_conn_state_process(struct sock *sk, struct sk_buff *skb)
{
int rc;
struct llc_sock *llc = llc_sk(skb->sk);
struct llc_conn_state_ev *ev = llc_conn_ev(skb);
skb_get(skb);
ev->ind_prim = ev->cfm_prim = 0;
rc = llc_conn_service(skb->sk, skb);
if (unlikely(rc != 0)) {
printk(KERN_ERR "%s: llc_conn_service failed\n", __func__);
goto out_kfree_skb;
}
if (unlikely(!ev->ind_prim && !ev->cfm_prim)) {
if (!skb->next)
goto out_kfree_skb;
goto out_skb_put;
}
if (unlikely(ev->ind_prim && ev->cfm_prim))
skb_get(skb);
switch (ev->ind_prim) {
case LLC_DATA_PRIM:
llc_save_primitive(sk, skb, LLC_DATA_PRIM);
if (unlikely(sock_queue_rcv_skb(sk, skb))) {
printk(KERN_ERR "%s: sock_queue_rcv_skb failed!\n",
__func__);
kfree_skb(skb);
}
break;
case LLC_CONN_PRIM:
skb_queue_tail(&sk->sk_receive_queue, skb);
sk->sk_state_change(sk);
break;
case LLC_DISC_PRIM:
sock_hold(sk);
if (sk->sk_type == SOCK_STREAM &&
sk->sk_state == TCP_ESTABLISHED) {
sk->sk_shutdown = SHUTDOWN_MASK;
sk->sk_socket->state = SS_UNCONNECTED;
sk->sk_state = TCP_CLOSE;
if (!sock_flag(sk, SOCK_DEAD)) {
sock_set_flag(sk, SOCK_DEAD);
sk->sk_state_change(sk);
}
}
kfree_skb(skb);
sock_put(sk);
break;
case LLC_RESET_PRIM:
printk(KERN_INFO "%s: received a reset ind!\n", __func__);
kfree_skb(skb);
break;
default:
if (ev->ind_prim) {
printk(KERN_INFO "%s: received unknown %d prim!\n",
__func__, ev->ind_prim);
kfree_skb(skb);
}
break;
}
switch (ev->cfm_prim) {
case LLC_DATA_PRIM:
if (!llc_data_accept_state(llc->state))
sk->sk_write_space(sk);
else
rc = llc->failed_data_req = 1;
break;
case LLC_CONN_PRIM:
if (sk->sk_type == SOCK_STREAM &&
sk->sk_state == TCP_SYN_SENT) {
if (ev->status) {
sk->sk_socket->state = SS_UNCONNECTED;
sk->sk_state = TCP_CLOSE;
} else {
sk->sk_socket->state = SS_CONNECTED;
sk->sk_state = TCP_ESTABLISHED;
}
sk->sk_state_change(sk);
}
break;
case LLC_DISC_PRIM:
sock_hold(sk);
if (sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_CLOSING) {
sk->sk_socket->state = SS_UNCONNECTED;
sk->sk_state = TCP_CLOSE;
sk->sk_state_change(sk);
}
sock_put(sk);
break;
case LLC_RESET_PRIM:
printk(KERN_INFO "%s: received a reset conf!\n", __func__);
break;
default:
if (ev->cfm_prim) {
printk(KERN_INFO "%s: received unknown %d prim!\n",
__func__, ev->cfm_prim);
break;
}
goto out_skb_put;
}
out_kfree_skb:
kfree_skb(skb);
out_skb_put:
kfree_skb(skb);
return rc;
}
