int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
int err = 0;
int skb_len;
/* Cast skb->rcvbuf to unsigned... It's pointless, but reduces
number of warnings when compiling with -W --ANK
*/
if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
(unsigned)sk->sk_rcvbuf) {
err = -ENOMEM;
goto out;
}
err = sk_filter(sk, skb);
if (err)
goto out;
skb->dev = NULL;
skb_set_owner_r(skb, sk);
/* Cache the SKB length before we tack it onto the receive
* queue. Once it is added it no longer belongs to us and
* may be freed by other threads of control pulling packets
* from the queue.
*/
skb_len = skb->len;
skb_queue_tail(&sk->sk_receive_queue, skb);
if (!sock_flag(sk, SOCK_DEAD))
sk->sk_data_ready(sk, skb_len);
out:
return err;
}
/*
* Copy of sock_queue_rcv_skb (from sock.h) without
* bh_lock_sock() (its already held when this is called) which
* also allows data and other data to be queued to a socket.
*/
static __inline__ int dn_queue_skb(struct sock *sk, struct sk_buff *skb, int sig, struct sk_buff_head *queue)
{
int err;
/* Cast skb->rcvbuf to unsigned... It's pointless, but reduces
number of warnings when compiling with -W --ANK
*/
if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
(unsigned int)sk->sk_rcvbuf) {
err = -ENOMEM;
goto out;
}
err = sk_filter(sk, skb);
if (err)
goto out;
skb_set_owner_r(skb, sk);
skb_queue_tail(queue, skb);
if (!sock_flag(sk, SOCK_DEAD))
sk->sk_data_ready(sk);
out:
return err;
}
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;
}
/*
* Copy of sock_queue_rcv_skb (from sock.h) without
* bh_lock_sock() (its already held when this is called) which
* also allows data and other data to be queued to a socket.
*/
static __inline__ int dn_queue_skb(struct sock *sk, struct sk_buff *skb, int sig, struct sk_buff_head *queue)
{
int err;
/* Cast skb->rcvbuf to unsigned... It's pointless, but reduces
number of warnings when compiling with -W --ANK
*/
if (atomic_read(&sk->rmem_alloc) + skb->truesize >= (unsigned)sk->rcvbuf) {
err = -ENOMEM;
goto out;
}
err = sk_filter(sk, skb, 0);
if (err)
goto out;
skb_set_owner_r(skb, sk);
skb_queue_tail(queue, skb);
/* This code only runs from BH or BH protected context.
* Therefore the plain read_lock is ok here. -DaveM
*/
read_lock(&sk->callback_lock);
if (!sk->dead) {
struct socket *sock = sk->socket;
wake_up_interruptible(sk->sleep);
if (sock && sock->fasync_list &&
!test_bit(SOCK_ASYNC_WAITDATA, &sock->flags))
__kill_fasync(sock->fasync_list, sig,
(sig == SIGURG) ? POLL_PRI : POLL_IN);
}
read_unlock(&sk->callback_lock);
out:
return err;
}
static __inline__ int dn_queue_skb(struct sock *sk, struct sk_buff *skb, int sig, struct sk_buff_head *queue)
{
int err;
int skb_len;
if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
(unsigned)sk->sk_rcvbuf) {
err = -ENOMEM;
goto out;
}
err = sk_filter(sk, skb);
if (err)
goto out;
skb_len = skb->len;
skb_set_owner_r(skb, sk);
skb_queue_tail(queue, skb);
if (!sock_flag(sk, SOCK_DEAD))
sk->sk_data_ready(sk, skb_len);
out:
return err;
}
int
sk_filter_test(void)
{
struct sk_buff *skb = &test_skbuff;
struct sk_filter *filter = &test_filter;
return sk_filter(skb, filter);
}
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;
}
/* The socket must have it's spinlock held when we get
* here.
*
* We have a potential double-lock case here, so even when
* doing backlog processing we use the BH locking scheme.
* This is because we cannot sleep with the original spinlock
* held.
*/
static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
{
struct ipv6_pinfo *np = inet6_sk(sk);
struct sk_buff *opt_skb = NULL;
/* Imagine: socket is IPv6. IPv4 packet arrives,
goes to IPv4 receive handler and backlogged.
From backlog it always goes here. Kerboom...
Fortunately, dccp_rcv_established and rcv_established
handle them correctly, but it is not case with
dccp_v6_hnd_req and dccp_v6_ctl_send_reset(). --ANK
*/
if (skb->protocol == htons(ETH_P_IP))
return dccp_v4_do_rcv(sk, skb);
if (sk_filter(sk, skb))
goto discard;
/*
* socket locking is here for SMP purposes as backlog rcv is currently
* called with bh processing disabled.
*/
/* Do Stevens' IPV6_PKTOPTIONS.
Yes, guys, it is the only place in our code, where we
may make it not affecting IPv4.
The rest of code is protocol independent,
and I do not like idea to uglify IPv4.
Actually, all the idea behind IPV6_PKTOPTIONS
looks not very well thought. For now we latch
options, received in the last packet, enqueued
by tcp. Feel free to propose better solution.
--ANK (980728)
*/
if (np->rxopt.all)
/*
* FIXME: Add handling of IPV6_PKTOPTIONS skb. See the comments below
* (wrt ipv6_pktopions) and net/ipv6/tcp_ipv6.c for an example.
*/
opt_skb = skb_clone(skb, GFP_ATOMIC);
if (sk->sk_state == DCCP_OPEN) { /* Fast path */
if (dccp_rcv_established(sk, skb, dccp_hdr(skb), skb->len))
goto reset;
if (opt_skb) {
/* XXX This is where we would goto ipv6_pktoptions. */
__kfree_skb(opt_skb);
}
return 0;
}
/*
* Step 3: Process LISTEN state
* If S.state == LISTEN,
* If P.type == Request or P contains a valid Init Cookie option,
* (* Must scan the packet's options to check for Init
* Cookies. Only Init Cookies are processed here,
* however; other options are processed in Step 8. This
* scan need only be performed if the endpoint uses Init
* Cookies *)
* (* Generate a new socket and switch to that socket *)
* Set S := new socket for this port pair
* S.state = RESPOND
* Choose S.ISS (initial seqno) or set from Init Cookies
* Initialize S.GAR := S.ISS
* Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies
* Continue with S.state == RESPOND
* (* A Response packet will be generated in Step 11 *)
* Otherwise,
* Generate Reset(No Connection) unless P.type == Reset
* Drop packet and return
*
* NOTE: the check for the packet types is done in
* dccp_rcv_state_process
*/
if (sk->sk_state == DCCP_LISTEN) {
struct sock *nsk = dccp_v6_hnd_req(sk, skb);
if (nsk == NULL)
goto discard;
/*
* Queue it on the new socket if the new socket is active,
* otherwise we just shortcircuit this and continue with
* the new socket..
*/
if (nsk != sk) {
if (dccp_child_process(sk, nsk, skb))
goto reset;
if (opt_skb != NULL)
__kfree_skb(opt_skb);
return 0;
}
}
if (dccp_rcv_state_process(sk, skb, dccp_hdr(skb), skb->len))
goto reset;
if (opt_skb) {
/* XXX This is where we would goto ipv6_pktoptions. */
__kfree_skb(opt_skb);
}
return 0;
reset:
dccp_v6_ctl_send_reset(sk, skb);
discard:
if (opt_skb != NULL)
__kfree_skb(opt_skb);
kfree_skb(skb);
return 0;
}
/* The socket must have it's spinlock held when we get
* here.
*
* We have a potential double-lock case here, so even when
* doing backlog processing we use the BH locking scheme.
* This is because we cannot sleep with the original spinlock
* held.
*/
static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
{
struct ipv6_pinfo *np = inet6_sk(sk);
struct sk_buff *opt_skb = NULL;
/* Imagine: socket is IPv6. IPv4 packet arrives,
goes to IPv4 receive handler and backlogged.
From backlog it always goes here. Kerboom...
Fortunately, dccp_rcv_established and rcv_established
handle them correctly, but it is not case with
dccp_v6_hnd_req and dccp_v6_ctl_send_reset(). --ANK
*/
if (skb->protocol == htons(ETH_P_IP))
return dccp_v4_do_rcv(sk, skb);
if (sk_filter(sk, skb))
goto discard;
/*
* socket locking is here for SMP purposes as backlog rcv is currently
* called with bh processing disabled.
*/
/* Do Stevens' IPV6_PKTOPTIONS.
Yes, guys, it is the only place in our code, where we
may make it not affecting IPv4.
The rest of code is protocol independent,
and I do not like idea to uglify IPv4.
Actually, all the idea behind IPV6_PKTOPTIONS
looks not very well thought. For now we latch
options, received in the last packet, enqueued
by tcp. Feel free to propose better solution.
--ANK (980728)
*/
if (np->rxopt.all)
opt_skb = skb_clone(skb, GFP_ATOMIC);
if (sk->sk_state == DCCP_OPEN) { /* Fast path */
if (dccp_rcv_established(sk, skb, dccp_hdr(skb), skb->len))
goto reset;
if (opt_skb)
goto ipv6_pktoptions;
return 0;
}
/*
* Step 3: Process LISTEN state
* If S.state == LISTEN,
* If P.type == Request or P contains a valid Init Cookie option,
* (* Must scan the packet's options to check for Init
* Cookies. Only Init Cookies are processed here,
* however; other options are processed in Step 8. This
* scan need only be performed if the endpoint uses Init
* Cookies *)
* (* Generate a new socket and switch to that socket *)
* Set S := new socket for this port pair
* S.state = RESPOND
* Choose S.ISS (initial seqno) or set from Init Cookies
* Initialize S.GAR := S.ISS
* Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies
* Continue with S.state == RESPOND
* (* A Response packet will be generated in Step 11 *)
* Otherwise,
* Generate Reset(No Connection) unless P.type == Reset
* Drop packet and return
*
* NOTE: the check for the packet types is done in
* dccp_rcv_state_process
*/
if (dccp_rcv_state_process(sk, skb, dccp_hdr(skb), skb->len))
goto reset;
if (opt_skb)
goto ipv6_pktoptions;
return 0;
reset:
dccp_v6_ctl_send_reset(sk, skb);
discard:
if (opt_skb != NULL)
__kfree_skb(opt_skb);
kfree_skb(skb);
return 0;
/* Handling IPV6_PKTOPTIONS skb the similar
* way it's done for net/ipv6/tcp_ipv6.c
*/
ipv6_pktoptions:
if (!((1 << sk->sk_state) & (DCCPF_CLOSED | DCCPF_LISTEN))) {
if (np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo)
np->mcast_oif = inet6_iif(opt_skb);
if (np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim)
np->mcast_hops = ipv6_hdr(opt_skb)->hop_limit;
if (np->rxopt.bits.rxflow || np->rxopt.bits.rxtclass)
np->rcv_flowinfo = ip6_flowinfo(ipv6_hdr(opt_skb));
if (np->repflow)
np->flow_label = ip6_flowlabel(ipv6_hdr(opt_skb));
if (ipv6_opt_accepted(sk, opt_skb,
&DCCP_SKB_CB(opt_skb)->header.h6)) {
skb_set_owner_r(opt_skb, sk);
memmove(IP6CB(opt_skb),
&DCCP_SKB_CB(opt_skb)->header.h6,
sizeof(struct inet6_skb_parm));
opt_skb = xchg(&np->pktoptions, opt_skb);
} else {
__kfree_skb(opt_skb);
opt_skb = xchg(&np->pktoptions, NULL);
}
}
kfree_skb(opt_skb);
return 0;
}