int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
{
int rc = NET_RX_SUCCESS;
if (sk_filter(sk, skb))
goto discard_and_relse;
skb->dev = NULL;
if (nested)
bh_lock_sock_nested(sk);
else
bh_lock_sock(sk);
if (!sock_owned_by_user(sk)) {
/*
* trylock + unlock semantics:
*/
mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
rc = sk->sk_backlog_rcv(sk, skb);
mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
} else
sk_add_backlog(sk, skb);
bh_unlock_sock(sk);
out:
sock_put(sk);
return rc;
discard_and_relse:
kfree_skb(skb);
goto out;
}
static u32 dispatch(struct tipc_port *tport, struct sk_buff *buf)
{
struct sock *sk = (struct sock *)tport->usr_handle;
u32 res;
/*
* Process message if socket is unlocked; otherwise add to backlog queue
*
* This code is based on sk_receive_skb(), but must be distinct from it
* since a TIPC-specific filter/reject mechanism is utilized
*/
bh_lock_sock(sk);
if (!sock_owned_by_user(sk)) {
res = filter_rcv(sk, buf);
} else {
if (sk_add_backlog(sk, buf))
res = TIPC_ERR_OVERLOAD;
else
res = TIPC_OK;
}
bh_unlock_sock(sk);
return res;
}
void llc_conn_handler(struct llc_sap *sap, struct sk_buff *skb)
{
struct llc_addr saddr, daddr;
struct sock *sk;
llc_pdu_decode_sa(skb, saddr.mac);
llc_pdu_decode_ssap(skb, &saddr.lsap);
llc_pdu_decode_da(skb, daddr.mac);
llc_pdu_decode_dsap(skb, &daddr.lsap);
sk = __llc_lookup(sap, &saddr, &daddr);
if (!sk)
goto drop;
bh_lock_sock(sk);
/*
* This has to be done here and not at the upper layer ->accept
* method because of the way the PROCOM state machine works:
* it needs to set several state variables (see, for instance,
* llc_adm_actions_2 in net/llc/llc_c_st.c) and send a packet to
* the originator of the new connection, and this state has to be
* in the newly created struct sock private area. -acme
*/
if (unlikely(sk->sk_state == TCP_LISTEN)) {
struct sock *newsk = llc_create_incoming_sock(sk, skb->dev,
&saddr, &daddr);
if (!newsk)
goto drop_unlock;
skb_set_owner_r(skb, newsk);
} else {
/*
* Can't be skb_set_owner_r, this will be done at the
* llc_conn_state_process function, later on, when we will use
* skb_queue_rcv_skb to send it to upper layers, this is
* another trick required to cope with how the PROCOM state
* machine works. -acme
*/
skb->sk = sk;
}
if (!sock_owned_by_user(sk))
llc_conn_rcv(sk, skb);
else {
;
llc_set_backlog_type(skb, LLC_PACKET);
if (sk_add_backlog(sk, skb))
goto drop_unlock;
}
out:
bh_unlock_sock(sk);
sock_put(sk);
return;
drop:
kfree_skb(skb);
return;
drop_unlock:
kfree_skb(skb);
goto out;
}
static int x25_receive_data(struct sk_buff *skb, struct x25_neigh *nb)
{
struct sock *sk;
unsigned short frametype;
unsigned int lci;
frametype = skb->data[2];
lci = ((skb->data[0] << 8) & 0xF00) + ((skb->data[1] << 0) & 0x0FF);
/*
* LCI of zero is always for us, and its always a link control
* frame.
*/
if (lci == 0) {
x25_link_control(skb, nb, frametype);
return 0;
}
/*
* Find an existing socket.
*/
if ((sk = x25_find_socket(lci, nb)) != NULL) {
int queued = 1;
skb->h.raw = skb->data;
bh_lock_sock(sk);
if (!sock_owned_by_user(sk)) {
queued = x25_process_rx_frame(sk, skb);
} else {
sk_add_backlog(sk, skb);
}
bh_unlock_sock(sk);
return queued;
}
/*
* Is is a Call Request ? if so process it.
*/
if (frametype == X25_CALL_REQUEST)
return x25_rx_call_request(skb, nb, lci);
/*
* Its not a Call Request, nor is it a control frame.
* Let caller throw it away.
*/
/*
x25_transmit_clear_request(nb, lci, 0x0D);
*/
if (frametype != X25_CLEAR_CONFIRMATION)
printk(KERN_DEBUG "x25_receive_data(): unknown frame type %2x\n",frametype);
return 0;
}
static int x25_receive_data(struct sk_buff *skb, struct x25_neigh *nb)
{
struct sock *sk;
unsigned short frametype;
unsigned int lci;
if (!pskb_may_pull(skb, X25_STD_MIN_LEN))
return 0;
frametype = skb->data[2];
lci = ((skb->data[0] << 8) & 0xF00) + ((skb->data[1] << 0) & 0x0FF);
if (lci == 0) {
x25_link_control(skb, nb, frametype);
return 0;
}
if ((sk = x25_find_socket(lci, nb)) != NULL) {
int queued = 1;
skb_reset_transport_header(skb);
bh_lock_sock(sk);
if (!sock_owned_by_user(sk)) {
queued = x25_process_rx_frame(sk, skb);
} else {
queued = !sk_add_backlog(sk, skb);
}
bh_unlock_sock(sk);
sock_put(sk);
return queued;
}
if (frametype == X25_CALL_REQUEST)
return x25_rx_call_request(skb, nb, lci);
if (x25_forward_data(lci, nb, skb)) {
if (frametype == X25_CLEAR_CONFIRMATION) {
x25_clear_forward_by_lci(lci);
}
kfree_skb(skb);
return 1;
}
if (frametype != X25_CLEAR_CONFIRMATION)
printk(KERN_DEBUG "x25_receive_data(): unknown frame type %2x\n",frametype);
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);
}
}
}
static int lapd_dispatch_mph_primitive(struct sk_buff *skb)
{
struct sock *sk;
struct hlist_node *node;
struct lapd_device *dev = to_lapd_dev(skb->dev);
int queued = FALSE;
read_lock_bh(&lapd_hash_lock);
sk_for_each(sk, node, lapd_get_hash(dev)) {
struct lapd_sock *lapd_sock = to_lapd_sock(sk);
if (lapd_sock->dev == dev &&
sk->sk_state == LAPD_SK_STATE_MGMT) {
struct sk_buff *new_skb;
if (!queued) {
new_skb = skb;
queued = TRUE;
} else {
new_skb = skb_clone(skb, GFP_ATOMIC);
}
new_skb->sk = sk;
lapd_bh_lock_sock(lapd_sock);
if (!sock_owned_by_user(&lapd_sock->sk)) {
queued = lapd_mgmt_queue_primitive(lapd_sock,
skb);
} else {
#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,33)
sk_add_backlog(&lapd_sock->sk, skb);
#else
__sk_add_backlog(&lapd_sock->sk, skb);
#endif
queued = TRUE;
}
lapd_bh_unlock_sock(lapd_sock);
}
}
read_unlock_bh(&lapd_hash_lock);
return queued;
}
void llc_conn_handler(struct llc_sap *sap, struct sk_buff *skb)
{
struct llc_addr saddr, daddr;
struct sock *sk;
llc_pdu_decode_sa(skb, saddr.mac);
llc_pdu_decode_ssap(skb, &saddr.lsap);
llc_pdu_decode_da(skb, daddr.mac);
llc_pdu_decode_dsap(skb, &daddr.lsap);
sk = __llc_lookup(sap, &saddr, &daddr);
if (!sk)
goto drop;
bh_lock_sock(sk);
if (unlikely(sk->sk_state == TCP_LISTEN)) {
struct sock *newsk = llc_create_incoming_sock(sk, skb->dev,
&saddr, &daddr);
if (!newsk)
goto drop_unlock;
skb_set_owner_r(skb, newsk);
} else {
skb->sk = sk;
}
if (!sock_owned_by_user(sk))
llc_conn_rcv(sk, skb);
else {
dprintk("%s: adding to backlog...\n", __func__);
llc_set_backlog_type(skb, LLC_PACKET);
if (sk_add_backlog(sk, skb))
goto drop_unlock;
}
out:
bh_unlock_sock(sk);
sock_put(sk);
return;
drop:
kfree_skb(skb);
return;
drop_unlock:
kfree_skb(skb);
goto out;
}
int sk_receive_skb(struct sock *sk, struct sk_buff *skb)
{
int rc = NET_RX_SUCCESS;
if (sk_filter(sk, skb, 0))
goto discard_and_relse;
skb->dev = NULL;
bh_lock_sock(sk);
if (!sock_owned_by_user(sk))
rc = sk->sk_backlog_rcv(sk, skb);
else
sk_add_backlog(sk, skb);
bh_unlock_sock(sk);
out:
sock_put(sk);
return rc;
discard_and_relse:
kfree_skb(skb);
goto out;
}
static int lapd_pass_frame_to_socket(
struct lapd_sock *lapd_sock,
struct sk_buff *skb)
{
int queued;
/* Ensure serialization within a socket */
lapd_bh_lock_sock(lapd_sock);
if (!sock_owned_by_user(&lapd_sock->sk)) {
queued = lapd_dlc_recv(lapd_sock, skb);
} else {
#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,33)
sk_add_backlog(&lapd_sock->sk, skb);
#else
__sk_add_backlog(&lapd_sock->sk, skb);
#endif
queued = 1;
}
lapd_bh_unlock_sock(lapd_sock);
return queued;
}
static int dn_nsp_rx_packet(struct sk_buff *skb)
{
struct dn_skb_cb *cb = DN_SKB_CB(skb);
struct sock *sk = NULL;
unsigned char *ptr = (unsigned char *)skb->data;
unsigned short reason = NSP_REASON_NL;
skb->h.raw = skb->data;
cb->nsp_flags = *ptr++;
if (decnet_debug_level & 2)
printk(KERN_DEBUG "dn_nsp_rx: Message type 0x%02x\n", (int)cb->nsp_flags);
if (skb->len < 2)
goto free_out;
if (cb->nsp_flags & 0x83)
goto free_out;
/*
* Returned packets...
* Swap src & dst and look up in the normal way.
*/
if (cb->rt_flags & DN_RT_F_RTS) {
unsigned short tmp = cb->dst_port;
cb->dst_port = cb->src_port;
cb->src_port = tmp;
tmp = cb->dst;
cb->dst = cb->src;
cb->src = tmp;
sk = dn_find_by_skb(skb);
goto got_it;
}
/*
* Filter out conninits and useless packet types
*/
if ((cb->nsp_flags & 0x0c) == 0x08) {
switch(cb->nsp_flags & 0x70) {
case 0x00: /* NOP */
case 0x70: /* Reserved */
case 0x50: /* Reserved, Phase II node init */
goto free_out;
case 0x10:
case 0x60:
sk = dn_find_listener(skb, &reason);
goto got_it;
}
}
if (skb->len < 3)
goto free_out;
/*
* Grab the destination address.
*/
cb->dst_port = *(unsigned short *)ptr;
cb->src_port = 0;
ptr += 2;
/*
* If not a connack, grab the source address too.
*/
if (skb->len >= 5) {
cb->src_port = *(unsigned short *)ptr;
ptr += 2;
skb_pull(skb, 5);
}
/*
* Find the socket to which this skb is destined.
*/
sk = dn_find_by_skb(skb);
got_it:
if (sk != NULL) {
struct dn_scp *scp = DN_SK(sk);
int ret;
/* Reset backoff */
scp->nsp_rxtshift = 0;
bh_lock_sock(sk);
ret = NET_RX_SUCCESS;
if (decnet_debug_level & 8)
printk(KERN_DEBUG "NSP: 0x%02x 0x%02x 0x%04x 0x%04x %d\n",
(int)cb->rt_flags, (int)cb->nsp_flags,
(int)cb->src_port, (int)cb->dst_port,
(int)sk->lock.users);
if (sk->lock.users == 0)
ret = dn_nsp_backlog_rcv(sk, skb);
else
sk_add_backlog(sk, skb);
bh_unlock_sock(sk);
sock_put(sk);
return ret;
}
return dn_nsp_no_socket(skb, reason);
free_out:
kfree_skb(skb);
return NET_RX_DROP;
}
int ax8netfilter_udp_queue_rcv_skb(struct sock * sk, struct sk_buff *skb)
{
struct udp_sock *up = udp_sk(sk);
int rc;
int is_udplite = IS_UDPLITE(sk);
/*
* Charge it to the socket, dropping if the queue is full.
*/
if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb))
goto drop;
nf_reset(skb);
if (up->encap_type) {
/*
* This is an encapsulation socket so pass the skb to
* the socket's udp_encap_rcv() hook. Otherwise, just
* fall through and pass this up the UDP socket.
* up->encap_rcv() returns the following value:
* =0 if skb was successfully passed to the encap
* handler or was discarded by it.
* >0 if skb should be passed on to UDP.
* <0 if skb should be resubmitted as proto -N
*/
/* if we're overly short, let UDP handle it */
if (skb->len > sizeof(struct udphdr) &&
up->encap_rcv != NULL) {
int ret;
ret = (*up->encap_rcv)(sk, skb);
if (ret <= 0) {
UDP_INC_STATS_BH(sock_net(sk),
UDP_MIB_INDATAGRAMS,
is_udplite);
return -ret;
}
}
/* FALLTHROUGH -- it's a UDP Packet */
}
/*
* UDP-Lite specific tests, ignored on UDP sockets
*/
if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) {
/*
* MIB statistics other than incrementing the error count are
* disabled for the following two types of errors: these depend
* on the application settings, not on the functioning of the
* protocol stack as such.
*
* RFC 3828 here recommends (sec 3.3): "There should also be a
* way ... to ... at least let the receiving application block
* delivery of packets with coverage values less than a value
* provided by the application."
*/
if (up->pcrlen == 0) { /* full coverage was set */
LIMIT_NETDEBUG(KERN_WARNING "UDPLITE: partial coverage "
"%d while full coverage %d requested\n",
UDP_SKB_CB(skb)->cscov, skb->len);
goto drop;
}
/* The next case involves violating the min. coverage requested
* by the receiver. This is subtle: if receiver wants x and x is
* greater than the buffersize/MTU then receiver will complain
* that it wants x while sender emits packets of smaller size y.
* Therefore the above ...()->partial_cov statement is essential.
*/
if (UDP_SKB_CB(skb)->cscov < up->pcrlen) {
LIMIT_NETDEBUG(KERN_WARNING
"UDPLITE: coverage %d too small, need min %d\n",
UDP_SKB_CB(skb)->cscov, up->pcrlen);
goto drop;
}
}
if (sk->sk_filter) {
if (udp_lib_checksum_complete(skb))
goto drop;
}
rc = 0;
bh_lock_sock(sk);
if (!sock_owned_by_user(sk))
rc = ax8netfilter___udp_queue_rcv_skb(sk, skb);
else
sk_add_backlog(sk, skb);
bh_unlock_sock(sk);
return rc;
drop:
UDP_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
kfree_skb(skb);
return -1;
}
