C++ sock_queue_rcv_skb函数代码示例

static int nr_queue_rx_frame(struct sock *sk, struct sk_buff *skb, int more)
{
	struct sk_buff *skbo, *skbn = skb;

	skb_pull(skb, NR_NETWORK_LEN + NR_TRANSPORT_LEN);

	nr_start_idletimer(sk);

	if (more) {
		sk->protinfo.nr->fraglen += skb->len;
		skb_queue_tail(&sk->protinfo.nr->frag_queue, skb);
		return 0;
	}

	if (!more && sk->protinfo.nr->fraglen > 0) {	/* End of fragment */
		sk->protinfo.nr->fraglen += skb->len;
		skb_queue_tail(&sk->protinfo.nr->frag_queue, skb);

		if ((skbn = alloc_skb(sk->protinfo.nr->fraglen, GFP_ATOMIC)) == NULL)
			return 1;

		skbn->h.raw = skbn->data;

		while ((skbo = skb_dequeue(&sk->protinfo.nr->frag_queue)) != NULL) {
			memcpy(skb_put(skbn, skbo->len), skbo->data, skbo->len);
			kfree_skb(skbo);
		}

		sk->protinfo.nr->fraglen = 0;		
	}

	return sock_queue_rcv_skb(sk, skbn);
}

static void raw_rcv(struct sk_buff *skb, void *data)
{
	struct sock *sk = (struct sock *)data;
	struct raw_sock *ro = raw_sk(sk);
	struct sockaddr_can *addr;

	/* check the received tx sock reference */
	if ((!ro->recv_own_msgs) && (skb->sk == sk))
		return;

	/* clone the given skb to be able to enqueue it into the rcv queue */
	skb = skb_clone(skb, GFP_ATOMIC);
	if (!skb)
		return;

	/*
	 *  Put the datagram to the queue so that raw_recvmsg() can
	 *  get it from there.  We need to pass the interface index to
	 *  raw_recvmsg().  We pass a whole struct sockaddr_can in skb->cb
	 *  containing the interface index.
	 */

	BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can));
	addr = (struct sockaddr_can *)skb->cb;
	memset(addr, 0, sizeof(*addr));
	addr->can_family  = AF_CAN;
	addr->can_ifindex = skb->dev->ifindex;

	if (sock_queue_rcv_skb(sk, skb) < 0)
		kfree_skb(skb);
}

static void raw_rcv(struct sk_buff *oskb, void *data)
{
	struct sock *sk = (struct sock *)data;
	struct raw_sock *ro = raw_sk(sk);
	struct sockaddr_can *addr;
	struct sk_buff *skb;
	unsigned int *pflags;

	
	if (!ro->recv_own_msgs && oskb->sk == sk)
		return;

	
	skb = skb_clone(oskb, GFP_ATOMIC);
	if (!skb)
		return;


	BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can));
	addr = (struct sockaddr_can *)skb->cb;
	memset(addr, 0, sizeof(*addr));
	addr->can_family  = AF_CAN;
	addr->can_ifindex = skb->dev->ifindex;

	
	pflags = raw_flags(skb);
	*pflags = 0;
	if (oskb->sk)
		*pflags |= MSG_DONTROUTE;
	if (oskb->sk == sk)
		*pflags |= MSG_CONFIRM;

	if (sock_queue_rcv_skb(sk, skb) < 0)
		kfree_skb(skb);
}

static inline int l2cap_data_channel(struct l2cap_conn *conn, __u16 cid, struct sk_buff *skb)
{
	struct sock *sk;

	sk = l2cap_get_chan_by_scid(&conn->chan_list, cid);
	if (!sk) {
		BT_DBG("unknown cid 0x%4.4x", cid);
		goto drop;
	}

	BT_DBG("sk %p, len %d", sk, skb->len);

	if (sk->state != BT_CONNECTED)
		goto drop;

	if (l2cap_pi(sk)->imtu < skb->len)
		goto drop;

	/* If socket recv buffers overflows we drop data here 
	 * which is *bad* because L2CAP has to be reliable. 
	 * But we don't have any other choice. L2CAP doesn't 
	 * provide flow control mechanism */ 
	
	if (!sock_queue_rcv_skb(sk, skb))
		goto done;

drop:
	kfree_skb(skb);

done:
	if (sk) bh_unlock_sock(sk);
	return 0;
}

static inline int l2cap_conless_channel(struct l2cap_conn *conn, __u16 psm, struct sk_buff *skb)
{
	struct sock *sk;

	sk = l2cap_get_sock_by_psm(0, psm, conn->src);
	if (!sk)
		goto drop;

	BT_DBG("sk %p, len %d", sk, skb->len);

	if (sk->state != BT_BOUND && sk->state != BT_CONNECTED)
		goto drop;

	if (l2cap_pi(sk)->imtu < skb->len)
		goto drop;

	if (!sock_queue_rcv_skb(sk, skb))
		goto done;

drop:
	kfree_skb(skb);

done:
	if (sk) bh_unlock_sock(sk);
	return 0;
}

static void rawsock_data_exchange_complete(void *context, struct sk_buff *skb,
								int err)
{
	struct sock *sk = (struct sock *) context;

	BUG_ON(in_irq());

	nfc_dbg("sk=%p err=%d", sk, err);

	if (err)
		goto error;

	err = rawsock_add_header(skb);
	if (err)
		goto error;

	err = sock_queue_rcv_skb(sk, skb);
	if (err)
		goto error;

	spin_lock_bh(&sk->sk_write_queue.lock);
	if (!skb_queue_empty(&sk->sk_write_queue))
		schedule_work(&nfc_rawsock(sk)->tx_work);
	else
		nfc_rawsock(sk)->tx_work_scheduled = false;
	spin_unlock_bh(&sk->sk_write_queue.lock);

	sock_put(sk);
	return;

error:
	rawsock_report_error(sk, err);
	sock_put(sk);
}

/* Queue an skb for a sock. */
static int pn_backlog_rcv(struct sock *sk, struct sk_buff *skb)
{
	int err = sock_queue_rcv_skb(sk, skb);

	if (err < 0)
		kfree_skb(skb);
	return err ? NET_RX_DROP : NET_RX_SUCCESS;
}

/*
 *	This is where all valid I frames are sent to, to be dispatched to
 *	whichever protocol requires them.
 */
int ax25_rx_iframe(ax25_cb *ax25, struct sk_buff *skb)
{
	int (*func)(struct sk_buff *, ax25_cb *);
	volatile int queued = 0;
	unsigned char pid;

	if (skb == NULL) return 0;

	ax25_start_idletimer(ax25);

	pid = *skb->data;

#ifdef CONFIG_INET
	if (pid == AX25_P_IP) {
		/* working around a TCP bug to keep additional listeners
		 * happy. TCP re-uses the buffer and destroys the original
		 * content.
		 */
		struct sk_buff *skbn = skb_copy(skb, GFP_ATOMIC);
		if (skbn != NULL) {
			kfree_skb(skb);
			skb = skbn;
		}

		skb_pull(skb, 1);	/* Remove PID */
		skb->h.raw    = skb->data;
		skb->nh.raw   = skb->data;
		skb->dev      = ax25->ax25_dev->dev;
		skb->pkt_type = PACKET_HOST;
		skb->protocol = htons(ETH_P_IP);
		ip_rcv(skb, skb->dev, 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->ax25_dev->values[AX25_VALUES_CONMODE] == 2) {
		if ((!ax25->pidincl && ax25->sk->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;
}

static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
	int err;

	err = sock_queue_rcv_skb(sk, skb);
	if (err)
		kfree_skb(skb);

	return err;
}

static int raw_rcv_skb(struct sock * sk, struct sk_buff * skb)
{
	/* Charge it to the socket. */

	if (sock_queue_rcv_skb(sk, skb) < 0) {
		kfree_skb(skb);
		return NET_RX_DROP;
	}

	return NET_RX_SUCCESS;
}

static int raw_rcv_skb(struct sock * sk, struct sk_buff * skb)
{
	/* Charge it to the socket. */
	
	if (sock_queue_rcv_skb(sk, skb) < 0) {
		/* FIXME: increment a raw drops counter here */
		kfree_skb(skb);
		return NET_RX_DROP;
	}

	return NET_RX_SUCCESS;
}

static inline int rawv6_rcv_skb(struct sock * sk, struct sk_buff * skb)
{
	/* Charge it to the socket. */
	if (sock_queue_rcv_skb(sk,skb)<0) {
		ipv6_statistics.Ip6InDiscards++;
		kfree_skb(skb);
		return 0;
	}

	ipv6_statistics.Ip6InDelivers++;
	return 0;
}

static int raw_rcv_skb(struct sock * sk, struct sk_buff * skb)
{
	

	ipv4_pktinfo_prepare(skb);
	if (sock_queue_rcv_skb(sk, skb) < 0) {
		kfree_skb(skb);
		return NET_RX_DROP;
	}

	return NET_RX_SUCCESS;
}

static int raw_rcv_skb(struct sock * sk, struct sk_buff * skb)
{
	/* Charge it to the socket. */
	
	if (sock_queue_rcv_skb(sk, skb) < 0) {
		IP_INC_STATS(IpInDiscards);
		kfree_skb(skb);
		return NET_RX_DROP;
	}

	IP_INC_STATS(IpInDelivers);
	return NET_RX_SUCCESS;
}

static void raw_rcv(struct sk_buff *oskb, void *data)
{
	struct sock *sk = (struct sock *)data;
	struct raw_sock *ro = raw_sk(sk);
	struct sockaddr_can *addr;
	struct sk_buff *skb;
	unsigned int *pflags;

	/* check the received tx sock reference */
	if (!ro->recv_own_msgs && oskb->sk == sk)
		return;

	/* do not pass frames with DLC > 8 to a legacy socket */
	if (!ro->fd_frames) {
		struct canfd_frame *cfd = (struct canfd_frame *)oskb->data;

		if (unlikely(cfd->len > CAN_MAX_DLEN))
			return;
	}

	/* clone the given skb to be able to enqueue it into the rcv queue */
	skb = skb_clone(oskb, GFP_ATOMIC);
	if (!skb)
		return;

	/*
	 *  Put the datagram to the queue so that raw_recvmsg() can
	 *  get it from there.  We need to pass the interface index to
	 *  raw_recvmsg().  We pass a whole struct sockaddr_can in skb->cb
	 *  containing the interface index.
	 */

	BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can));
	addr = (struct sockaddr_can *)skb->cb;
	memset(addr, 0, sizeof(*addr));
	addr->can_family  = AF_CAN;
	addr->can_ifindex = skb->dev->ifindex;

	/* add CAN specific message flags for raw_recvmsg() */
	pflags = raw_flags(skb);
	*pflags = 0;
	if (oskb->sk)
		*pflags |= MSG_DONTROUTE;
	if (oskb->sk == sk)
		*pflags |= MSG_CONFIRM;

	if (sock_queue_rcv_skb(sk, skb) < 0)
		kfree_skb(skb);
}