C++ skb_copy_datagram_iovec函数代码示例

int raw_recvmsg(struct sock *sk, struct msghdr *msg, int len,
     int noblock, int flags,int *addr_len)
{
	int copied=0;
	struct sk_buff *skb;
	int err;
	struct sockaddr_in *sin=(struct sockaddr_in *)msg->msg_name;

	if (flags & MSG_OOB)
		return -EOPNOTSUPP;
		
	if (sk->shutdown & RCV_SHUTDOWN) 
		return(0);

	if (addr_len) 
		*addr_len=sizeof(*sin);

	skb=skb_recv_datagram(sk,flags,noblock,&err);
	if(skb==NULL)
 		return err;

	copied = min(len, skb->len);
	
	skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
	sk->stamp=skb->stamp;

	/* Copy the address. */
	if (sin) 
	{
		sin->sin_family = AF_INET;
		sin->sin_addr.s_addr = skb->daddr;
	}
	skb_free_datagram(sk, skb);
	return (copied);
}

/**
 *	skb_copy_and_csum_datagram_iovec - Copy and checkum skb to user iovec.
 *	@skb: skbuff
 *	@hlen: hardware length
 *	@iov: io vector
 *
 *	Caller _must_ check that skb will fit to this iovec.
 *
 *	Returns: 0       - success.
 *		 -EINVAL - checksum failure.
 *		 -EFAULT - fault during copy. Beware, in this case iovec
 *			   can be modified!
 */
int skb_copy_and_csum_datagram_iovec(struct sk_buff *skb,
				     int hlen, struct iovec *iov)
{
	__wsum csum;
	int chunk = skb->len - hlen;

	/* Skip filled elements.
	 * Pretty silly, look at memcpy_toiovec, though 8)
	 */
	while (!iov->iov_len)
		iov++;

	if (iov->iov_len < chunk) {
		if (__skb_checksum_complete(skb))
			goto csum_error;
		if (skb_copy_datagram_iovec(skb, hlen, iov, chunk))
			goto fault;
	} else {
		csum = csum_partial(skb->data, hlen, skb->csum);
		if (skb_copy_and_csum_datagram(skb, hlen, iov->iov_base,
					       chunk, &csum))
			goto fault;
		if (csum_fold(csum))
			goto csum_error;
		if (unlikely(skb->ip_summed == CHECKSUM_COMPLETE))
			netdev_rx_csum_fault(skb->dev);
		iov->iov_len -= chunk;
		iov->iov_base += chunk;
	}
	return 0;
csum_error:
	return -EINVAL;
fault:
	return -EFAULT;
}

static int rawsock_recvmsg(struct kiocb *iocb, struct socket *sock,
				struct msghdr *msg, size_t len, int flags)
{
	int noblock = flags & MSG_DONTWAIT;
	struct sock *sk = sock->sk;
	struct sk_buff *skb;
	int copied;
	int rc;

	nfc_dbg("sock=%p sk=%p len=%zu flags=%d", sock, sk, len, flags);

	skb = skb_recv_datagram(sk, flags, noblock, &rc);
	if (!skb)
		return rc;

	msg->msg_namelen = 0;

	copied = skb->len;
	if (len < copied) {
		msg->msg_flags |= MSG_TRUNC;
		copied = len;
	}

	rc = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);

	skb_free_datagram(sk, skb);

	return rc ? : copied;
}

static int hci_sock_recvmsg(struct socket *sock, struct msghdr *msg, int len, int flags, struct scm_cookie *scm)
{
	int noblock = flags & MSG_DONTWAIT;
	struct sock *sk = sock->sk;
	struct sk_buff *skb;
	int copied, err;

	BT_DBG("sock %p, sk %p", sock, sk);

	if (flags & (MSG_OOB))
		return -EOPNOTSUPP;

	if (sk->state == BT_CLOSED)
		return 0;

	if (!(skb = skb_recv_datagram(sk, flags, noblock, &err)))
		return err;

	msg->msg_namelen = 0;

	copied = skb->len;
	if (len < copied) {
		msg->msg_flags |= MSG_TRUNC;
		copied = len;
	}

	skb->h.raw = skb->data;
	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);

	hci_sock_cmsg(sk, msg, skb);
	
	skb_free_datagram(sk, skb);

	return err ? : copied;
}

static int raw_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
		       size_t len, int noblock, int flags, int *addr_len)
{
	struct inet_sock *inet = inet_sk(sk);
	size_t copied = 0;
	int err = -EOPNOTSUPP;
	struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name;
	struct sk_buff *skb;

	if (flags & MSG_OOB)
		goto out;

	if (addr_len)
		*addr_len = sizeof(*sin);

	if (flags & MSG_ERRQUEUE) {
		err = ip_recv_error(sk, msg, len);
		goto out;
	}

	skb = skb_recv_datagram(sk, flags, noblock, &err);
	if (!skb)
		goto out;
	if (ccs_socket_post_recvmsg_permission(sk, skb, flags)) {
		err = -EAGAIN; /* Hope less harmful than -EPERM. */
		goto out;
	}

	copied = skb->len;
	if (len < copied) {
		msg->msg_flags |= MSG_TRUNC;
		copied = len;
	}

	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
	if (err)
		goto done;

	sock_recv_ts_and_drops(msg, sk, skb);

	/* Copy the address. */
	if (sin) {
		sin->sin_family = AF_INET;
		sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
		sin->sin_port = 0;
		memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
	}
	if (inet->cmsg_flags)
		ip_cmsg_recv(msg, skb);
	if (flags & MSG_TRUNC)
		copied = skb->len;
done:
	skb_free_datagram(sk, skb);
out:
	if (err)
		return err;
	return copied;
}

static int pep_recvmsg(struct kiocb *iocb, struct sock *sk,
			struct msghdr *msg, size_t len, int noblock,
			int flags, int *addr_len)
{
	struct sk_buff *skb;
	int err;

	if (flags & ~(MSG_OOB|MSG_PEEK|MSG_TRUNC|MSG_DONTWAIT|MSG_WAITALL|
			MSG_NOSIGNAL|MSG_CMSG_COMPAT))
		return -EOPNOTSUPP;

	if (unlikely(1 << sk->sk_state & (TCPF_LISTEN | TCPF_CLOSE)))
		return -ENOTCONN;

	if ((flags & MSG_OOB) || sock_flag(sk, SOCK_URGINLINE)) {
		/* Dequeue and acknowledge control request */
		struct pep_sock *pn = pep_sk(sk);

		if (flags & MSG_PEEK)
			return -EOPNOTSUPP;
		skb = skb_dequeue(&pn->ctrlreq_queue);
		if (skb) {
			pep_ctrlreq_error(sk, skb, PN_PIPE_NO_ERROR,
						GFP_KERNEL);
			msg->msg_flags |= MSG_OOB;
			goto copy;
		}
		if (flags & MSG_OOB)
			return -EINVAL;
	}

	skb = skb_recv_datagram(sk, flags, noblock, &err);
	lock_sock(sk);
	if (skb == NULL) {
		if (err == -ENOTCONN && sk->sk_state == TCP_CLOSE_WAIT)
			err = -ECONNRESET;
		release_sock(sk);
		return err;
	}

	if (sk->sk_state == TCP_ESTABLISHED)
		pipe_grant_credits(sk);
	release_sock(sk);
copy:
	msg->msg_flags |= MSG_EOR;
	if (skb->len > len)
		msg->msg_flags |= MSG_TRUNC;
	else
		len = skb->len;

	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, len);
	if (!err)
		err = (flags & MSG_TRUNC) ? skb->len : len;

	skb_free_datagram(sk, skb);
	return err;
}

/*
 *	Copy a datagram to a linear buffer.
 */
int skb_copy_datagram(const struct sk_buff *skb, int offset, char __user *to, int size)
{
	struct iovec iov = {
		.iov_base = to,
		.iov_len =size,
	};

	return skb_copy_datagram_iovec(skb, offset, &iov, size);
}

static int netlink_recvmsg(struct socket *sock, struct msghdr *msg, int len,
			   int flags, struct scm_cookie *scm)
{
	struct sock *sk = sock->sk;
	int noblock = flags&MSG_DONTWAIT;
	int copied;
	struct sk_buff *skb;
	int err;

	if (flags&MSG_OOB)
		return -EOPNOTSUPP;

	copied = 0;

	skb = skb_recv_datagram(sk,flags,noblock,&err);
	if (skb==NULL)
		goto out;

	msg->msg_namelen = 0;

	copied = skb->len;
	if (len < copied) {
		msg->msg_flags |= MSG_TRUNC;
		copied = len;
	}

	skb->h.raw = skb->data;
	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);

	if (msg->msg_name) {
		struct sockaddr_nl *addr = (struct sockaddr_nl*)msg->msg_name;
		addr->nl_family = AF_NETLINK;
		addr->nl_pid	= NETLINK_CB(skb).pid;
		addr->nl_groups	= NETLINK_CB(skb).dst_groups;
		msg->msg_namelen = sizeof(*addr);
	}

	scm->creds = *NETLINK_CREDS(skb);
	skb_free_datagram(sk, skb);

	if (sk->protinfo.af_netlink->cb
	    && atomic_read(&sk->rmem_alloc) <= sk->rcvbuf/2)
		netlink_dump(sk);

out:
	if (skb_queue_len(&sk->receive_queue) <= sk->rcvbuf/2) {
		if (skb_queue_len(&sk->receive_queue) == 0)
			clear_bit(0, &sk->protinfo.af_netlink->state);
		if (!test_bit(0, &sk->protinfo.af_netlink->state))
			wake_up_interruptible(&sk->protinfo.af_netlink->wait);
	}
	return err ? : copied;
}

/*
 *	Handle MSG_ERRQUEUE
 */
int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
{
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct sock_exterr_skb *serr;
	struct sk_buff *skb, *skb2;
	struct sockaddr_in6 *sin;
	struct {
		struct sock_extended_err ee;
		struct sockaddr_in6	 offender;
	} errhdr;
	int err;
	int copied;

	err = -EAGAIN;
	skb = skb_dequeue(&sk->sk_error_queue);
	if (skb == NULL)
		goto out;

	copied = skb->len;
	if (copied > len) {
		msg->msg_flags |= MSG_TRUNC;
		copied = len;
	}
	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
	if (err)
		goto out_free_skb;

	sock_recv_timestamp(msg, sk, skb);

	serr = SKB_EXT_ERR(skb);

	sin = (struct sockaddr_in6 *)msg->msg_name;
	if (sin) {
		const unsigned char *nh = skb_network_header(skb);
		sin->sin6_family = AF_INET6;
		sin->sin6_flowinfo = 0;
		sin->sin6_port = serr->port;
		if (skb->protocol == htons(ETH_P_IPV6)) {
			const struct ipv6hdr *ip6h = container_of((struct in6_addr *)(nh + serr->addr_offset),
								  struct ipv6hdr, daddr);
			sin->sin6_addr = ip6h->daddr;
			if (np->sndflow)
				sin->sin6_flowinfo = ip6_flowinfo(ip6h);
			sin->sin6_scope_id =
				ipv6_iface_scope_id(&sin->sin6_addr,
						    IP6CB(skb)->iif);
		} else {
			ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset),
					       &sin->sin6_addr);
			sin->sin6_scope_id = 0;
		}
		*addr_len = sizeof(*sin);
	}

static int pn_recvmsg(struct kiocb *iocb, struct sock *sk,
			struct msghdr *msg, size_t len, int noblock,
			int flags, int *addr_len)
{
	struct sk_buff *skb = NULL;
	struct sockaddr_pn sa;
	int rval = -EOPNOTSUPP;
	int copylen;

	if (flags & ~(MSG_PEEK|MSG_TRUNC|MSG_DONTWAIT|MSG_NOSIGNAL|
			MSG_CMSG_COMPAT))
		goto out_nofree;

	if (addr_len)
		*addr_len = sizeof(sa);

	skb = skb_recv_datagram(sk, flags, noblock, &rval);
	if (skb == NULL)
		goto out_nofree;

	pn_skb_get_src_sockaddr(skb, &sa);

	copylen = skb->len;
	if (len < copylen) {
		msg->msg_flags |= MSG_TRUNC;
		copylen = len;
	}

	rval = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copylen);
	if (rval) {
		rval = -EFAULT;
		goto out;
	}

	rval = (flags & MSG_TRUNC) ? skb->len : copylen;

	if (msg->msg_name != NULL)
		memcpy(msg->msg_name, &sa, sizeof(struct sockaddr_pn));

#ifdef CONFIG_SAMSUNG_PHONE_SVNET
	/* svent RX debugging */
	if (sk->sk_receive_queue.qlen > 30)
//		printk(KERN_DEBUG "svn %s, sk = %p, qlen = %d\n", __func__, sk,
;
#endif

out:
	skb_free_datagram(sk, skb);

out_nofree:
	return rval;
}

int rawv6_recvmsg(struct sock *sk, struct msghdr *msg, int len,
		  int noblock, int flags, int *addr_len)
{
	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)msg->msg_name;
	struct sk_buff *skb;
	int copied, err;

	if (flags & MSG_OOB)
		return -EOPNOTSUPP;
		
	if (addr_len) 
		*addr_len=sizeof(*sin6);

	if (flags & MSG_ERRQUEUE)
		return ipv6_recv_error(sk, msg, len);

	skb = skb_recv_datagram(sk, flags, noblock, &err);
	if (!skb)
		goto out;

	copied = skb->tail - skb->h.raw;
  	if (copied > len) {
  		copied = len;
  		msg->msg_flags |= MSG_TRUNC;
  	}

	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
	sk->stamp=skb->stamp;
	if (err)
		goto out_free;

	/* Copy the address. */
	if (sin6) {
		sin6->sin6_family = AF_INET6;
		memcpy(&sin6->sin6_addr, &skb->nh.ipv6h->saddr, 
		       sizeof(struct in6_addr));
		sin6->sin6_flowinfo = 0;
		sin6->sin6_scope_id = 0;
		if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
			sin6->sin6_scope_id = 
				((struct inet6_skb_parm *) skb->cb)->iif;
	}

	if (sk->net_pinfo.af_inet6.rxopt.all)
		datagram_recv_ctl(sk, msg, skb);
	err = copied;

out_free:
	skb_free_datagram(sk, skb);
out:
	return err;
}

static int raw_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
		       size_t len, int noblock, int flags, int *addr_len)
{
	struct inet_sock *inet = inet_sk(sk);
	size_t copied = 0;
	int err = -EOPNOTSUPP;
	struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name;
	struct sk_buff *skb;

	if (flags & MSG_OOB)
		goto out;

	if (addr_len)
		*addr_len = sizeof(*sin);

	if (flags & MSG_ERRQUEUE) {
		err = ip_recv_error(sk, msg, len);
		goto out;
	}

	skb = skb_recv_datagram(sk, flags, noblock, &err);
	if (!skb)
		goto out;

	copied = skb->len;
	if (len < copied) {
		msg->msg_flags |= MSG_TRUNC;
		copied = len;
	}

	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
	if (err)
		goto done;

	sock_recv_timestamp(msg, sk, skb);

	/* Copy the address. */
	if (sin) {
		sin->sin_family = AF_INET;
		sin->sin_addr.s_addr = skb->nh.iph->saddr;
		memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
	}
	if (inet->cmsg_flags)
		ip_cmsg_recv(msg, skb);
	if (flags & MSG_TRUNC)
		copied = skb->len;
done:
	skb_free_datagram(sk, skb);
out:	return err ? err : copied;
}

/*
 *	Handle IPV6_RECVPATHMTU
 */
int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
		     int *addr_len)
{
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct sk_buff *skb;
	struct sockaddr_in6 *sin;
	struct ip6_mtuinfo mtu_info;
	int err;
	int copied;

	err = -EAGAIN;
	skb = xchg(&np->rxpmtu, NULL);
	if (skb == NULL)
		goto out;

	copied = skb->len;
	if (copied > len) {
		msg->msg_flags |= MSG_TRUNC;
		copied = len;
	}
	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
	if (err)
		goto out_free_skb;

	sock_recv_timestamp(msg, sk, skb);

	memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info));

	sin = (struct sockaddr_in6 *)msg->msg_name;
	if (sin) {
		sin->sin6_family = AF_INET6;
		sin->sin6_flowinfo = 0;
		sin->sin6_port = 0;
		sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id;
		ipv6_addr_copy(&sin->sin6_addr, &mtu_info.ip6m_addr.sin6_addr);
		*addr_len = sizeof(*sin);
	}

	put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info);

	err = copied;

out_free_skb:
	kfree_skb(skb);
out:
	return err;
}

/**
 *	llc_ui_recvmsg - copy received data to the socket user.
 *	@sock: Socket to copy data from.
 *	@msg: Various user space related information.
 *	@size: Size of user buffer.
 *	@flags: User specified flags.
 *
 *	Copy received data to the socket user.
 *	Returns non-negative upon success, negative otherwise.
 */
static int llc_ui_recvmsg(struct kiocb *iocb, struct socket *sock,
			  struct msghdr *msg, size_t size, int flags)
{
	struct sock *sk = sock->sk;
	struct sockaddr_llc *uaddr = (struct sockaddr_llc *)msg->msg_name;
	struct sk_buff *skb;
	size_t copied = 0;
	int rc = -ENOMEM, timeout;
	int noblock = flags & MSG_DONTWAIT;

	dprintk("%s: receiving in %02X from %02X\n", __FUNCTION__,
		llc_sk(sk)->laddr.lsap, llc_sk(sk)->daddr.lsap);
	lock_sock(sk);
	timeout = sock_rcvtimeo(sk, noblock);
	rc = llc_ui_wait_for_data(sk, timeout);
	if (rc) {
		dprintk("%s: llc_ui_wait_for_data failed recv "
			"in %02X from %02X\n", __FUNCTION__,
			llc_sk(sk)->laddr.lsap, llc_sk(sk)->daddr.lsap);
		goto out;
	}
	skb = skb_dequeue(&sk->sk_receive_queue);
	if (!skb) /* shutdown */
		goto out;
	copied = skb->len;
	if (copied > size)
		copied = size;
	rc = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
	if (rc)
		goto dgram_free;
	if (skb->len > copied) {
		skb_pull(skb, copied);
		skb_queue_head(&sk->sk_receive_queue, skb);
	}
	if (uaddr)
		memcpy(uaddr, llc_ui_skb_cb(skb), sizeof(*uaddr));
	msg->msg_namelen = sizeof(*uaddr);
	if (!skb->list) {
dgram_free:
		kfree_skb(skb);
	}
out:
	release_sock(sk);
	return rc ? : copied;
}

static int pn_recvmsg(struct kiocb *iocb, struct sock *sk,
			struct msghdr *msg, size_t len, int noblock,
			int flags, int *addr_len)
{
	struct sk_buff *skb = NULL;
	struct sockaddr_pn sa;
	int rval = -EOPNOTSUPP;
	int copylen;

	if (flags & ~(MSG_PEEK|MSG_TRUNC|MSG_DONTWAIT|MSG_NOSIGNAL|
			MSG_CMSG_COMPAT))
		goto out_nofree;

	skb = skb_recv_datagram(sk, flags, noblock, &rval);
	if (skb == NULL)
		goto out_nofree;

	pn_skb_get_src_sockaddr(skb, &sa);

	copylen = skb->len;
	if (len < copylen) {
		msg->msg_flags |= MSG_TRUNC;
		copylen = len;
	}

	rval = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copylen);
	if (rval) {
		rval = -EFAULT;
		goto out;
	}

	rval = (flags & MSG_TRUNC) ? skb->len : copylen;

	if (msg->msg_name != NULL) {
		__sockaddr_check_size(sizeof(sa));
		memcpy(msg->msg_name, &sa, sizeof(sa));
		*addr_len = sizeof(sa);
	}

out:
	skb_free_datagram(sk, skb);

out_nofree:
	return rval;
}