/**
* 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_opt* 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_ac_inc_npta_value - tries to make value of npta greater
* @sk: current connection structure.
* @skb: current event.
*
* After "inc_cntr" times calling of this action, "npta" increase by one.
* this action tries to make vale of "npta" greater as possible; number of
* acknowledgements decreases by increasing of "npta". Returns 0 for
* success, 1 otherwise.
*/
static int llc_conn_ac_inc_npta_value(struct sock *sk, struct sk_buff *skb)
{
struct llc_sock *llc = llc_sk(sk);
if (!llc->inc_cntr) {
llc->dec_step = 0;
llc->dec_cntr = llc->inc_cntr = 2;
++llc->npta;
if (llc->npta > 127)
llc->npta = 127 ;
} else
--llc->inc_cntr;
return 0;
}
/**
* llc_process_tmr_ev - timer backend
* @sk: active connection
* @skb: occurred event
*
* This function is called from timer callback functions. When connection
* is busy (during sending a data frame) timer expiration event must be
* queued. Otherwise this event can be sent to connection state machine.
* Queued events will process by llc_backlog_rcv function after sending
* data frame.
*/
static void llc_process_tmr_ev(struct sock *sk, struct sk_buff *skb)
{
if (llc_sk(sk)->state == LLC_CONN_OUT_OF_SVC) {
printk(KERN_WARNING "%s: timer called on closed connection\n",
__func__);
kfree_skb(skb);
} else {
if (!sock_owned_by_user(sk))
llc_conn_state_process(sk, skb);
else {
llc_set_backlog_type(skb, LLC_EVENT);
sk_add_backlog(sk, skb);
}
}
}
/**
* llc_conn_ac_adjust_npta_by_rnr - decreases "npta" by one
* @sk: current connection structure.
* @skb: current event.
*
* After receiving "dec_cntr" times RNR command, this action decreases
* "npta" by one. Returns 0 for success, 1 otherwise.
*/
int llc_conn_ac_adjust_npta_by_rnr(struct sock *sk, struct sk_buff *skb)
{
struct llc_sock *llc = llc_sk(sk);
if (llc->remote_busy_flag)
if (!llc->dec_step) {
if (!llc->dec_cntr) {
llc->inc_cntr = llc->dec_cntr = 2;
if (llc->npta > 0)
--llc->npta;
} else
--llc->dec_cntr;
}
return 0;
}
int llc_conn_ac_clear_remote_busy(struct sock *sk, struct sk_buff *skb)
{
struct llc_sock *llc = llc_sk(sk);
if (llc->remote_busy_flag) {
u8 nr;
struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
llc->remote_busy_flag = 0;
del_timer(&llc->busy_state_timer.timer);
nr = LLC_I_GET_NR(pdu);
llc_conn_resend_i_pdu_as_cmd(sk, nr, 0);
}
return 0;
}
/**
* llc_ui_connect - Connect to a remote llc2 mac + sap.
* @sock: Socket which will be connected to the remote destination.
* @uaddr: Remote and possibly the local address of the new connection.
* @addrlen: Size of uaddr structure.
* @flags: Operational flags specified by the user.
*
* Connect to a remote llc2 mac + sap. The caller must specify the
* destination mac and address to connect to. If the user hasn't previously
* called bind(2) with a smac the address of the first interface of the
* specified arp type will be used.
* This function will autobind if user did not previously call bind.
* Returns: 0 upon success, negative otherwise.
*/
static int llc_ui_connect(struct socket *sock, struct sockaddr *uaddr,
int addrlen, int flags)
{
struct sock *sk = sock->sk;
struct llc_sock *llc = llc_sk(sk);
struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr;
struct net_device *dev;
int rc = -EINVAL;
lock_sock(sk);
if (addrlen != sizeof(*addr))
goto out;
rc = -EAFNOSUPPORT;
if (addr->sllc_family != AF_LLC)
goto out;
/* bind connection to sap if user hasn't done it. */
if (sock_flag(sk, SOCK_ZAPPED)) {
/* bind to sap with null dev, exclusive */
rc = llc_ui_autobind(sock, addr);
if (rc)
goto out;
llc->daddr.lsap = addr->sllc_sap;
memcpy(llc->daddr.mac, addr->sllc_mac, IFHWADDRLEN);
}
dev = llc->dev;
if (sk->sk_type != SOCK_STREAM)
goto out;
rc = -EALREADY;
if (sock->state == SS_CONNECTING)
goto out;
sock->state = SS_CONNECTING;
sk->sk_state = TCP_SYN_SENT;
llc->link = llc_ui_next_link_no(llc->sap->laddr.lsap);
rc = llc_establish_connection(sk, dev->dev_addr,
addr->sllc_mac, addr->sllc_sap);
if (rc) {
dprintk("%s: llc_ui_send_conn failed :-(\n", __FUNCTION__);
sock->state = SS_UNCONNECTED;
sk->sk_state = TCP_CLOSE;
goto out;
}
rc = llc_ui_wait_for_conn(sk, sk->sk_rcvtimeo);
if (rc)
dprintk("%s: llc_ui_wait_for_conn failed=%d\n", __FUNCTION__, rc);
out:
release_sock(sk);
return rc;
}
int llc_conn_ac_send_i_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
{
int rc;
struct llc_sock *llc = llc_sk(sk);
struct llc_sap *sap = llc->sap;
llc_pdu_header_init(skb, LLC_PDU_TYPE_I, sap->laddr.lsap,
llc->daddr.lsap, LLC_PDU_CMD);
llc_pdu_init_as_i_cmd(skb, 0, llc->vS, llc->vR);
rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac);
if (likely(!rc)) {
llc_conn_send_pdu(sk, skb);
llc_conn_ac_inc_vs_by_1(sk, skb);
}
return 0;
}
/**
* llc_ui_bind - bind a socket to a specific address.
* @sock: Socket to bind an address to.
* @uaddr: Address the user wants the socket bound to.
* @addrlen: Length of the uaddr structure.
*
* Bind a socket to a specific address. For llc a user is able to bind to
* a specific sap only or mac + sap.
* If the user desires to bind to a specific mac + sap, it is possible to
* have multiple sap connections via multiple macs.
* Bind and autobind for that matter must enforce the correct sap usage
* otherwise all hell will break loose.
* Returns: 0 upon success, negative otherwise.
*/
static int llc_ui_bind(struct socket *sock, struct sockaddr *uaddr, int addrlen)
{
struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr;
struct sock *sk = sock->sk;
struct llc_sock *llc = llc_sk(sk);
struct llc_sap *sap;
int rc = -EINVAL;
dprintk("%s: binding %02X\n", __func__, addr->sllc_sap);
if (unlikely(!sock_flag(sk, SOCK_ZAPPED) || addrlen != sizeof(*addr)))
goto out;
rc = -EAFNOSUPPORT;
if (unlikely(addr->sllc_family != AF_LLC))
goto out;
rc = -ENODEV;
<<<<<<< HEAD
/**
* llc_conn_ac_send_i_rsp_f_set_ackpf - acknowledge received PDUs
* @sk: current connection structure
* @skb: current event
*
* Sends an I response PDU with f-bit set to ack_pf flag as acknowledge to
* all received PDUs which have not been acknowledged, yet. ack_pf flag is
* set to one if one PDU with p-bit set to one is received. Returns 0 for
* success, 1 otherwise.
*/
int llc_conn_ac_send_i_rsp_f_set_ackpf(struct sock *sk, struct sk_buff *skb)
{
int rc;
struct llc_opt *llc = llc_sk(sk);
struct llc_sap *sap = llc->sap;
llc_pdu_header_init(skb, LLC_PDU_TYPE_I, sap->laddr.lsap,
llc->daddr.lsap, LLC_PDU_RSP);
llc_pdu_init_as_i_cmd(skb, llc->ack_pf, llc->vS, llc->vR);
rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac);
if (!rc) {
llc_conn_send_pdu(sk, skb);
llc_conn_ac_inc_vs_by_1(sk, skb);
}
return rc;
}
/**
* llc_conn_ac_adjust_npta_by_rr - decreases "npta" by one
* @sk: current connection structure.
* @skb: current event.
*
* After receiving "dec_cntr" times RR command, this action decreases
* "npta" by one. Returns 0 for success, 1 otherwise.
*/
int llc_conn_ac_adjust_npta_by_rr(struct sock *sk, struct sk_buff *skb)
{
struct llc_sock *llc = llc_sk(sk);
if (!llc->connect_step && !llc->remote_busy_flag) {
if (!llc->dec_step) {
if (!llc->dec_cntr) {
llc->inc_cntr = llc->dec_cntr = 2;
if (llc->npta > 0)
llc->npta = llc->npta - 1;
} else
llc->dec_cntr -=1;
}
} else
llc->connect_step = 0 ;
return 0;
}
/**
* llc_ui_getsockopt - get connection specific socket info
* @sock: Socket to get information from.
* @level: Socket level user is requesting operations on.
* @optname: Operation name.
* @optval: Variable to return operation data in.
* @optlen: Length of optval.
*
* Get connection specific socket information.
*/
static int llc_ui_getsockopt(struct socket *sock, int level, int optname,
char __user *optval, int __user *optlen)
{
struct sock *sk = sock->sk;
struct llc_sock *llc = llc_sk(sk);
int val = 0, len = 0, rc = -EINVAL;
lock_sock(sk);
if (level != SOL_LLC)
goto out;
rc = get_user(len, optlen);
if (rc)
goto out;
rc = -EINVAL;
if (len != sizeof(int))
goto out;
switch (optname) {
case LLC_OPT_RETRY:
val = llc->n2; break;
case LLC_OPT_SIZE:
val = llc->n1; break;
case LLC_OPT_ACK_TMR_EXP:
val = llc->ack_timer.expire; break;
case LLC_OPT_P_TMR_EXP:
val = llc->pf_cycle_timer.expire; break;
case LLC_OPT_REJ_TMR_EXP:
val = llc->rej_sent_timer.expire; break;
case LLC_OPT_BUSY_TMR_EXP:
val = llc->busy_state_timer.expire; break;
case LLC_OPT_TX_WIN:
val = llc->k; break;
case LLC_OPT_RX_WIN:
val = llc->rw; break;
default:
rc = -ENOPROTOOPT;
goto out;
}
rc = 0;
if (put_user(len, optlen) || copy_to_user(optval, &val, len))
rc = -EFAULT;
out:
release_sock(sk);
return rc;
}
/**
* llc_conn_send_pdus - Sends queued PDUs
* @sk: active connection
*
* Sends queued pdus to MAC layer for transmission.
*/
static void llc_conn_send_pdus(struct sock *sk)
{
struct sk_buff *skb;
while ((skb = skb_dequeue(&sk->sk_write_queue)) != NULL) {
struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
if (LLC_PDU_TYPE_IS_I(pdu) &&
!(skb->dev->flags & IFF_LOOPBACK)) {
struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
skb_queue_tail(&llc_sk(sk)->pdu_unack_q, skb);
if (!skb2)
break;
skb = skb2;
}
dev_queue_xmit(skb);
}
}
int llc_conn_ac_rst_ind(struct sock *sk, struct sk_buff *skb)
{
u8 reason = 0;
int rc = 1;
struct llc_conn_state_ev *ev = llc_conn_ev(skb);
struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);
struct llc_opt *llc = llc_sk(sk);
switch (ev->type) {
case LLC_CONN_EV_TYPE_PDU:
if (LLC_PDU_IS_RSP(pdu) &&
LLC_PDU_TYPE_IS_U(pdu) &&
LLC_U_PDU_RSP(pdu) == LLC_2_PDU_RSP_FRMR) {
reason = LLC_RESET_REASON_LOCAL;
rc = 0;
} else if (LLC_PDU_IS_CMD(pdu) &&
LLC_PDU_TYPE_IS_U(pdu) &&
LLC_U_PDU_CMD(pdu) == LLC_2_PDU_CMD_SABME) {
reason = LLC_RESET_REASON_REMOTE;
rc = 0;
} else {
reason = 0;
rc = 1;
}
break;
case LLC_CONN_EV_TYPE_ACK_TMR:
case LLC_CONN_EV_TYPE_P_TMR:
case LLC_CONN_EV_TYPE_REJ_TMR:
case LLC_CONN_EV_TYPE_BUSY_TMR:
if (llc->retry_count > llc->n2) {
reason = LLC_RESET_REASON_LOCAL;
rc = 0;
} else
rc = 1;
break;
}
if (!rc) {
ev->reason = reason;
ev->ind_prim = LLC_RESET_PRIM;
}
return rc;
}
/**
* llc_conn_ac_send_ack_if_needed - check if ack is needed
* @sk: current connection structure
* @skb: current event
*
* Checks number of received PDUs which have not been acknowledged, yet,
* If number of them reaches to "npta"(Number of PDUs To Acknowledge) then
* sends an RR response as acknowledgement for them. Returns 0 for
* success, 1 otherwise.
*/
int llc_conn_ac_send_ack_if_needed(struct sock *sk, struct sk_buff *skb)
{
u8 pf_bit;
struct llc_opt *llc = llc_sk(sk);
llc_pdu_decode_pf_bit(skb, &pf_bit);
llc->ack_pf |= pf_bit & 1;
if (!llc->ack_must_be_send) {
llc->first_pdu_Ns = llc->vR;
llc->ack_must_be_send = 1;
llc->ack_pf = pf_bit & 1;
}
if (((llc->vR - llc->first_pdu_Ns + 129) % 128) >= llc->npta) {
llc_conn_ac_send_rr_rsp_f_set_ackpf(sk, skb);
llc->ack_must_be_send = 0;
llc->ack_pf = 0;
llc_conn_ac_inc_npta_value(sk, skb);
}
return 0;
}
int llc_conn_ac_conn_ind(struct sock *sk, struct sk_buff *skb)
{
int rc = -ENOTCONN;
u8 dsap;
struct llc_sap *sap;
llc_pdu_decode_dsap(skb, &dsap);
sap = llc_sap_find(dsap);
if (sap) {
struct llc_conn_state_ev *ev = llc_conn_ev(skb);
struct llc_opt *llc = llc_sk(sk);
llc_pdu_decode_sa(skb, llc->daddr.mac);
llc_pdu_decode_da(skb, llc->laddr.mac);
llc->dev = skb->dev;
ev->ind_prim = LLC_CONN_PRIM;
rc = 0;
}
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_ui_getname - return the address info of a socket
* @sock: Socket to get address of.
* @uaddr: Address structure to return information.
* @uaddrlen: Length of address structure.
* @peer: Does user want local or remote address information.
*
* Return the address information of a socket.
*/
static int llc_ui_getname(struct socket *sock, struct sockaddr *uaddr,
int *uaddrlen, int peer)
{
struct sockaddr_llc sllc;
struct sock *sk = sock->sk;
struct llc_sock *llc = llc_sk(sk);
int rc = 0;
lock_sock(sk);
if (sock_flag(sk, SOCK_ZAPPED))
goto out;
*uaddrlen = sizeof(sllc);
memset(uaddr, 0, *uaddrlen);
if (peer) {
rc = -ENOTCONN;
if (sk->sk_state != TCP_ESTABLISHED)
goto out;
if(llc->dev)
sllc.sllc_arphrd = llc->dev->type;
sllc.sllc_sap = llc->daddr.lsap;
memcpy(&sllc.sllc_mac, &llc->daddr.mac, IFHWADDRLEN);
} else {
rc = -EINVAL;
if (!llc->sap)
goto out;
sllc.sllc_sap = llc->sap->laddr.lsap;
if (llc->dev) {
sllc.sllc_arphrd = llc->dev->type;
memcpy(&sllc.sllc_mac, &llc->dev->dev_addr,
IFHWADDRLEN);
}
}
rc = 0;
sllc.sllc_family = AF_LLC;
memcpy(uaddr, &sllc, sizeof(sllc));
out:
release_sock(sk);
return rc;
}
/**
* llc_sk_reset - resets a connection
* @sk: LLC socket to reset
*
* Resets a connection to the out of service state. Stops its timers
* and frees any frames in the queues of the connection.
*/
void llc_sk_reset(struct sock *sk)
{
struct llc_sock *llc = llc_sk(sk);
llc_conn_ac_stop_all_timers(sk, NULL);
skb_queue_purge(&sk->sk_write_queue);
skb_queue_purge(&llc->pdu_unack_q);
llc->remote_busy_flag = 0;
llc->cause_flag = 0;
llc->retry_count = 0;
llc_conn_set_p_flag(sk, 0);
llc->f_flag = 0;
llc->s_flag = 0;
llc->ack_pf = 0;
llc->first_pdu_Ns = 0;
llc->ack_must_be_send = 0;
llc->dec_step = 1;
llc->inc_cntr = 2;
llc->dec_cntr = 2;
llc->X = 0;
llc->failed_data_req = 0 ;
llc->last_nr = 0;
}
/**
* llc_util_nr_inside_tx_window - check if sequence number is in tx window
* @sk: current connection.
* @nr: N(R) of received PDU.
*
* This routine checks if N(R) of received PDU is in range of transmit
* window; on the other hand checks if received PDU acknowledges some
* outstanding PDUs that are in transmit window. Returns 0 for success, 1
* otherwise.
*/
static u16 llc_util_nr_inside_tx_window(struct sock *sk, u8 nr)
{
u8 nr1, nr2;
struct sk_buff *skb;
struct llc_pdu_sn *pdu;
struct llc_opt *llc = llc_sk(sk);
int rc = 0;
if (llc->dev->flags & IFF_LOOPBACK)
goto out;
rc = 1;
if (!skb_queue_len(&llc->pdu_unack_q))
goto out;
skb = skb_peek(&llc->pdu_unack_q);
pdu = llc_pdu_sn_hdr(skb);
nr1 = LLC_I_GET_NS(pdu);
skb = skb_peek_tail(&llc->pdu_unack_q);
pdu = llc_pdu_sn_hdr(skb);
nr2 = LLC_I_GET_NS(pdu);
rc = !llc_circular_between(nr1, nr, (nr2 + 1) % LLC_2_SEQ_NBR_MODULO);
out:
return rc;
}
int llc_conn_ac_send_ack_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
{
int rc = -ENOBUFS;
struct llc_sock *llc = llc_sk(sk);
struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
if (nskb) {
struct llc_sap *sap = llc->sap;
llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
llc->daddr.lsap, LLC_PDU_RSP);
llc_pdu_init_as_rr_rsp(nskb, 0, llc->vR);
rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
if (unlikely(rc))
goto free;
llc_conn_send_pdu(sk, nskb);
}
out:
return rc;
free:
kfree_skb(nskb);
goto out;
}
/**
* 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_sock *llc = llc_sk(sk);
if (unlikely(llc->state == LLC_CONN_STATE_ADM))
goto out;
rc = -EBUSY;
if (unlikely(llc_data_accept_state(llc->state) || /* data_conn_refuse */
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_qualify_conn_ev - finds transition for event
* @sk: connection
* @skb: happened event
*
* This function finds transition that matches with happened event.
* Returns pointer to found transition on success, %NULL otherwise.
*/
static struct llc_conn_state_trans *llc_qualify_conn_ev(struct sock *sk,
struct sk_buff *skb)
{
struct llc_conn_state_trans **next_trans;
llc_conn_ev_qfyr_t *next_qualifier;
struct llc_conn_state_ev *ev = llc_conn_ev(skb);
struct llc_sock *llc = llc_sk(sk);
struct llc_conn_state *curr_state =
&llc_conn_state_table[llc->state - 1];
/* search thru events for this state until
* list exhausted or until no more
*/
for (next_trans = curr_state->transitions +
llc_find_offset(llc->state - 1, ev->type);
(*next_trans)->ev; next_trans++) {
if (!((*next_trans)->ev)(sk, skb)) {
/* got POSSIBLE event match; the event may require
* qualification based on the values of a number of
* state flags; if all qualifications are met (i.e.,
* if all qualifying functions return success, or 0,
* then this is THE event we're looking for
*/
for (next_qualifier = (*next_trans)->ev_qualifiers;
next_qualifier && *next_qualifier &&
!(*next_qualifier)(sk, skb); next_qualifier++)
/* nothing */;
if (!next_qualifier || !*next_qualifier)
/* all qualifiers executed successfully; this is
* our transition; return it so we can perform
* the associated actions & change the state
*/
return *next_trans;
}
}
return NULL;
}
/**
* llc_ui_autobind - automatically bind a socket to a sap
* @sock: socket to bind
* @addr: address to connect to
*
* Used by llc_ui_connect and llc_ui_sendmsg when the user hasn't
* specifically used llc_ui_bind to bind to an specific address/sap
*
* Returns: 0 upon success, negative otherwise.
*/
static int llc_ui_autobind(struct socket *sock, struct sockaddr_llc *addr)
{
struct sock *sk = sock->sk;
struct llc_sock *llc = llc_sk(sk);
struct llc_sap *sap;
int rc = -EINVAL;
if (!sock_flag(sk, SOCK_ZAPPED))
goto out;
rc = -ENODEV;
if (sk->sk_bound_dev_if) {
llc->dev = dev_get_by_index(&init_net, sk->sk_bound_dev_if);
if (llc->dev && addr->sllc_arphrd != llc->dev->type) {
dev_put(llc->dev);
llc->dev = NULL;
}
} else
llc->dev = dev_getfirstbyhwtype(&init_net, addr->sllc_arphrd);
if (!llc->dev)
goto out;
rc = -EUSERS;
llc->laddr.lsap = llc_ui_autoport();
if (!llc->laddr.lsap)
goto out;
rc = -EBUSY; /* some other network layer is using the sap */
sap = llc_sap_open(llc->laddr.lsap, NULL);
if (!sap)
goto out;
memcpy(llc->laddr.mac, llc->dev->dev_addr, IFHWADDRLEN);
memcpy(&llc->addr, addr, sizeof(llc->addr));
/* assign new connection to its SAP */
llc_sap_add_socket(sap, sk);
sock_reset_flag(sk, SOCK_ZAPPED);
rc = 0;
out:
return rc;
}
/**
* __llc_lookup_established - Finds connection for the remote/local sap/mac
* @sap: SAP
* @daddr: address of remote LLC (MAC + SAP)
* @laddr: address of local LLC (MAC + SAP)
*
* Search connection list of the SAP and finds connection using the remote
* mac, remote sap, local mac, and local sap. Returns pointer for
* connection found, %NULL otherwise.
* Caller has to make sure local_bh is disabled.
*/
static struct sock *__llc_lookup_established(struct llc_sap *sap,
struct llc_addr *daddr,
struct llc_addr *laddr)
{
struct sock *rc;
struct hlist_nulls_node *node;
int slot = llc_sk_laddr_hashfn(sap, laddr);
struct hlist_nulls_head *laddr_hb = &sap->sk_laddr_hash[slot];
rcu_read_lock();
again:
sk_nulls_for_each_rcu(rc, node, laddr_hb) {
if (llc_estab_match(sap, daddr, laddr, rc)) {
/* Extra checks required by SLAB_DESTROY_BY_RCU */
if (unlikely(!atomic_inc_not_zero(&rc->sk_refcnt)))
goto again;
if (unlikely(llc_sk(rc)->sap != sap ||
!llc_estab_match(sap, daddr, laddr, rc))) {
sock_put(rc);
continue;
}
goto found;
}
}
rc = NULL;
/*
* if the nulls value we got at the end of this lookup is
* not the expected one, we must restart lookup.
* We probably met an item that was moved to another chain.
*/
if (unlikely(get_nulls_value(node) != slot))
goto again;
found:
rcu_read_unlock();
return rc;
}
int llc_conn_ac_send_ack_cmd_p_set_1(struct sock *sk, struct sk_buff *skb)
{
int rc = -ENOBUFS;
struct sk_buff *nskb = llc_alloc_frame();
if (nskb) {
struct llc_opt *llc = llc_sk(sk);
struct llc_sap *sap = llc->sap;
nskb->dev = llc->dev;
llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
llc->daddr.lsap, LLC_PDU_CMD);
llc_pdu_init_as_rr_cmd(nskb, 1, llc->vR);
rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
if (rc)
goto free;
llc_conn_send_pdu(sk, nskb);
}
out:
return rc;
free:
kfree_skb(nskb);
goto out;
}
int llc_conn_ac_send_ua_rsp_f_set_f_flag(struct sock *sk, struct sk_buff *skb)
{
int rc = -ENOBUFS;
struct sk_buff *nskb = llc_alloc_frame();
if (nskb) {
struct llc_opt *llc = llc_sk(sk);
struct llc_sap *sap = llc->sap;
nskb->dev = llc->dev;
llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
llc->daddr.lsap, LLC_PDU_RSP);
llc_pdu_init_as_ua_rsp(nskb, llc->f_flag);
rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
if (rc)
goto free;
llc_conn_send_pdu(sk, nskb);
}
out:
return rc;
free:
kfree_skb(nskb);
goto out;
}
/**
* llc_ui_release - shutdown socket
* @sock: Socket to release.
*
* Shutdown and deallocate an existing socket.
*/
static int llc_ui_release(struct socket *sock)
{
struct sock *sk = sock->sk;
struct llc_sock *llc;
if (unlikely(sk == NULL))
goto out;
sock_hold(sk);
lock_sock(sk);
llc = llc_sk(sk);
dprintk("%s: closing local(%02X) remote(%02X)\n", __func__,
llc->laddr.lsap, llc->daddr.lsap);
if (!llc_send_disc(sk))
llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo);
if (!sock_flag(sk, SOCK_ZAPPED))
llc_sap_remove_socket(llc->sap, sk);
release_sock(sk);
if (llc->dev)
dev_put(llc->dev);
sock_put(sk);
llc_sk_free(sk);
out:
return 0;
}
static struct llc_conn_state_trans *llc_qualify_conn_ev(struct sock *sk,
struct sk_buff *skb)
{
struct llc_conn_state_trans **next_trans;
llc_conn_ev_qfyr_t *next_qualifier;
struct llc_conn_state_ev *ev = llc_conn_ev(skb);
struct llc_sock *llc = llc_sk(sk);
struct llc_conn_state *curr_state =
&llc_conn_state_table[llc->state - 1];
for (next_trans = curr_state->transitions +
llc_find_offset(llc->state - 1, ev->type);
(*next_trans)->ev; next_trans++) {
if (!((*next_trans)->ev)(sk, skb)) {
for (next_qualifier = (*next_trans)->ev_qualifiers;
next_qualifier && *next_qualifier &&
!(*next_qualifier)(sk, skb); next_qualifier++)
;
if (!next_qualifier || !*next_qualifier)
return *next_trans;
}
}
return NULL;
}
/**
* llc_establish_connection - Called by upper layer to establish a conn
* @sk: connection
* @lmac: local mac address
* @dmac: destination mac address
* @dsap: destination sap
*
* Upper layer calls this to establish an LLC connection with a remote
* machine. This function packages a proper event and sends it connection
* component state machine. Success or failure of connection
* establishment will inform to upper layer via calling it's confirm
* function and passing proper information.
*/
int llc_establish_connection(struct sock *sk, u8 *lmac, u8 *dmac, u8 dsap)
{
int rc = -EISCONN;
struct llc_addr laddr, daddr;
struct sk_buff *skb;
struct llc_sock *llc = llc_sk(sk);
struct sock *existing;
laddr.lsap = llc->sap->laddr.lsap;
daddr.lsap = dsap;
memcpy(daddr.mac, dmac, sizeof(daddr.mac));
memcpy(laddr.mac, lmac, sizeof(laddr.mac));
existing = llc_lookup_established(llc->sap, &daddr, &laddr);
if (existing) {
if (existing->sk_state == TCP_ESTABLISHED) {
sk = existing;
goto out_put;
} else
sock_put(existing);
}
sock_hold(sk);
rc = -ENOMEM;
skb = alloc_skb(0, GFP_ATOMIC);
if (skb) {
struct llc_conn_state_ev *ev = llc_conn_ev(skb);
ev->type = LLC_CONN_EV_TYPE_PRIM;
ev->prim = LLC_CONN_PRIM;
ev->prim_type = LLC_PRIM_TYPE_REQ;
skb_set_owner_w(skb, sk);
rc = llc_conn_state_process(sk, skb);
}
out_put:
sock_put(sk);
return rc;
}
int llc_conn_ac_send_disc_cmd_p_set_x(struct sock *sk, struct sk_buff *skb)
{
int rc = -ENOBUFS;
struct llc_sock *llc = llc_sk(sk);
struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_U, 0);
if (nskb) {
struct llc_sap *sap = llc->sap;
llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
llc->daddr.lsap, LLC_PDU_CMD);
llc_pdu_init_as_disc_cmd(nskb, 1);
rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
if (unlikely(rc))
goto free;
llc_conn_send_pdu(sk, nskb);
llc_conn_ac_set_p_flag_1(sk, skb);
}
out:
return rc;
free:
kfree_skb(nskb);
goto out;
}
