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nuttx/net/inet/inet_recvfrom.c

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/****************************************************************************
* net/inet/inet_recvfrom.c
*
* Copyright (C) 2007-2009, 2011-2018 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#ifdef CONFIG_NET
#include <sys/types.h>
#include <sys/socket.h>
#include <stdint.h>
#include <string.h>
#include <errno.h>
#include <debug.h>
#include <assert.h>
#include <arch/irq.h>
#include <nuttx/clock.h>
#include <nuttx/semaphore.h>
#include <nuttx/cancelpt.h>
#include <nuttx/net/net.h>
#include <nuttx/mm/iob.h>
#include <nuttx/net/netdev.h>
#include <nuttx/net/ip.h>
#include <nuttx/net/tcp.h>
#include <nuttx/net/udp.h>
#include "netdev/netdev.h"
#include "devif/devif.h"
#include "tcp/tcp.h"
#include "udp/udp.h"
#include "pkt/pkt.h"
#include "local/local.h"
#include "socket/socket.h"
#include "usrsock/usrsock.h"
#include "inet/inet.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#define IPv4BUF ((struct ipv4_hdr_s *)&dev->d_buf[NET_LL_HDRLEN(dev)])
#define IPv6BUF ((struct ipv6_hdr_s *)&dev->d_buf[NET_LL_HDRLEN(dev)])
#define UDPIPv4BUF ((struct udp_hdr_s *)&dev->d_buf[NET_LL_HDRLEN(dev) + IPv4_HDRLEN])
#define UDPIPv6BUF ((struct udp_hdr_s *)&dev->d_buf[NET_LL_HDRLEN(dev) + IPv6_HDRLEN])
#define TCPIPv4BUF ((struct tcp_hdr_s *)&dev->d_buf[NET_LL_HDRLEN(dev) + IPv4_HDRLEN])
#define TCPIPv6BUF ((struct tcp_hdr_s *)&dev->d_buf[NET_LL_HDRLEN(dev) + IPv6_HDRLEN])
/****************************************************************************
* Private Types
****************************************************************************/
#if defined(NET_UDP_HAVE_STACK) || defined(NET_TCP_HAVE_STACK)
struct inet_recvfrom_s
{
FAR struct socket *ir_sock; /* The parent socket structure */
#ifdef CONFIG_NET_SOCKOPTS
clock_t ir_starttime; /* rcv start time for determining timeout */
#endif
FAR struct devif_callback_s *ir_cb; /* Reference to callback instance */
sem_t ir_sem; /* Semaphore signals recv completion */
size_t ir_buflen; /* Length of receive buffer */
uint8_t *ir_buffer; /* Pointer to receive buffer */
FAR struct sockaddr *ir_from; /* Address of sender */
FAR socklen_t *ir_fromlen; /* Number of bytes allocated for address of sender */
ssize_t ir_recvlen; /* The received length */
int ir_result; /* Success:OK, failure:negated errno */
};
#endif /* NET_UDP_HAVE_STACK || NET_TCP_HAVE_STACK */
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: inet_update_recvlen
*
* Description:
* Update information about space available for new data and update size
* of data in buffer, This logic accounts for the case where
* inet_udp_readahead() sets state.ir_recvlen == -1 .
*
* Input Parameters:
* pstate recvfrom state structure
* recvlen size of new data appended to buffer
*
* Returned Value:
* None
*
****************************************************************************/
#if defined(NET_UDP_HAVE_STACK) || defined(NET_TCP_HAVE_STACK)
static inline void inet_update_recvlen(FAR struct inet_recvfrom_s *pstate,
size_t recvlen)
{
if (pstate->ir_recvlen < 0)
{
pstate->ir_recvlen = 0;
}
pstate->ir_recvlen += recvlen;
pstate->ir_buffer += recvlen;
pstate->ir_buflen -= recvlen;
}
#endif /* NET_UDP_HAVE_STACK || NET_TCP_HAVE_STACK */
/****************************************************************************
* Name: inet_recvfrom_newdata
*
* Description:
* Copy the read data from the packet
*
* Input Parameters:
* dev The structure of the network driver that generated the event.
* pstate recvfrom state structure
*
* Returned Value:
* The number of bytes taken from the packet.
*
* Assumptions:
* The network is locked.
*
****************************************************************************/
#if defined(NET_UDP_HAVE_STACK) || defined(NET_TCP_HAVE_STACK)
static size_t inet_recvfrom_newdata(FAR struct net_driver_s *dev,
FAR struct inet_recvfrom_s *pstate)
{
size_t recvlen;
/* Get the length of the data to return */
if (dev->d_len > pstate->ir_buflen)
{
recvlen = pstate->ir_buflen;
}
else
{
recvlen = dev->d_len;
}
/* Copy the new appdata into the user buffer */
memcpy(pstate->ir_buffer, dev->d_appdata, recvlen);
ninfo("Received %d bytes (of %d)\n", (int)recvlen, (int)dev->d_len);
/* Update the accumulated size of the data read */
inet_update_recvlen(pstate, recvlen);
return recvlen;
}
#endif /* NET_UDP_HAVE_STACK || NET_TCP_HAVE_STACK */
/****************************************************************************
* Name: inet_tcp_newdata
*
* Description:
* Copy the read data from the packet
*
* Input Parameters:
* dev The structure of the network driver that generated the event
* pstate recvfrom state structure
*
* Returned Value:
* None.
*
* Assumptions:
* The network is locked.
*
****************************************************************************/
#ifdef NET_TCP_HAVE_STACK
static inline void inet_tcp_newdata(FAR struct net_driver_s *dev,
FAR struct inet_recvfrom_s *pstate)
{
/* Take as much data from the packet as we can */
size_t recvlen = inet_recvfrom_newdata(dev, pstate);
/* If there is more data left in the packet that we could not buffer, then
* add it to the read-ahead buffers.
*/
if (recvlen < dev->d_len)
{
#ifdef CONFIG_NET_TCP_READAHEAD
FAR struct tcp_conn_s *conn = (FAR struct tcp_conn_s *)pstate->ir_sock->s_conn;
FAR uint8_t *buffer = (FAR uint8_t *)dev->d_appdata + recvlen;
uint16_t buflen = dev->d_len - recvlen;
#ifdef CONFIG_DEBUG_NET
uint16_t nsaved;
nsaved = tcp_datahandler(conn, buffer, buflen);
#else
(void)tcp_datahandler(conn, buffer, buflen);
#endif
/* There are complicated buffering issues that are not addressed fully
* here. For example, what if up_datahandler() cannot buffer the
* remainder of the packet? In that case, the data will be dropped but
* still ACKed. Therefore it would not be resent.
*
* This is probably not an issue here because we only get here if the
* read-ahead buffers are empty and there would have to be something
* serioulsy wrong with the configuration not to be able to buffer a
* partial packet in this context.
*/
#ifdef CONFIG_DEBUG_NET
if (nsaved < buflen)
{
nerr("ERROR: packet data not saved (%d bytes)\n", buflen - nsaved);
}
#endif
#else
nerr("ERROR: packet data lost (%d bytes)\n", dev->d_len - recvlen);
#endif
}
/* Indicate no data in the buffer */
dev->d_len = 0;
}
#endif /* NET_TCP_HAVE_STACK */
/****************************************************************************
* Name: inet_udp_newdata
*
* Description:
* Copy the read data from the packet
*
* Input Parameters:
* dev The sructure of the network driver that generated the event
* pstate recvfrom state structure
*
* Returned Value:
* None.
*
* Assumptions:
* The network is locked.
*
****************************************************************************/
#ifdef NET_UDP_HAVE_STACK
static inline void inet_udp_newdata(FAR struct net_driver_s *dev,
FAR struct inet_recvfrom_s *pstate)
{
/* Take as much data from the packet as we can */
(void)inet_recvfrom_newdata(dev, pstate);
/* Indicate no data in the buffer */
dev->d_len = 0;
}
#endif /* NET_UDP_HAVE_STACK */
/****************************************************************************
* Name: inet_tcp_readahead and inet_udp_readahead
*
* Description:
* Copy the read-ahead data from the packet
*
* Input Parameters:
* pstate recvfrom state structure
*
* Returned Value:
* None
*
* Assumptions:
* The network is locked.
*
****************************************************************************/
#if defined(NET_TCP_HAVE_STACK) && defined(CONFIG_NET_TCP_READAHEAD)
static inline void inet_tcp_readahead(struct inet_recvfrom_s *pstate)
{
FAR struct tcp_conn_s *conn = (FAR struct tcp_conn_s *)pstate->ir_sock->s_conn;
FAR struct iob_s *iob;
int recvlen;
/* Check there is any TCP data already buffered in a read-ahead
* buffer.
*/
while ((iob = iob_peek_queue(&conn->readahead)) != NULL &&
pstate->ir_buflen > 0)
{
DEBUGASSERT(iob->io_pktlen > 0);
/* Transfer that buffered data from the I/O buffer chain into
* the user buffer.
*/
recvlen = iob_copyout(pstate->ir_buffer, iob, pstate->ir_buflen, 0);
ninfo("Received %d bytes (of %d)\n", recvlen, iob->io_pktlen);
/* Update the accumulated size of the data read */
inet_update_recvlen(pstate, recvlen);
/* If we took all of the ata from the I/O buffer chain is empty, then
* release it. If there is still data available in the I/O buffer
* chain, then just trim the data that we have taken from the
* beginning of the I/O buffer chain.
*/
if (recvlen >= iob->io_pktlen)
{
FAR struct iob_s *tmp;
/* Remove the I/O buffer chain from the head of the read-ahead
* buffer queue.
*/
tmp = iob_remove_queue(&conn->readahead);
DEBUGASSERT(tmp == iob);
UNUSED(tmp);
/* And free the I/O buffer chain */
(void)iob_free_chain(iob);
}
else
{
/* The bytes that we have received from the head of the I/O
* buffer chain (probably changing the head of the I/O
* buffer queue).
*/
(void)iob_trimhead_queue(&conn->readahead, recvlen);
}
}
}
#endif /* NET_TCP_HAVE_STACK && CONFIG_NET_TCP_READAHEAD */
#if defined(NET_UDP_HAVE_STACK) && defined(CONFIG_NET_UDP_READAHEAD)
static inline void inet_udp_readahead(struct inet_recvfrom_s *pstate)
{
FAR struct udp_conn_s *conn = (FAR struct udp_conn_s *)pstate->ir_sock->s_conn;
FAR struct iob_s *iob;
int recvlen;
/* Check there is any UDP datagram already buffered in a read-ahead
* buffer.
*/
pstate->ir_recvlen = -1;
if ((iob = iob_peek_queue(&conn->readahead)) != NULL)
{
FAR struct iob_s *tmp;
uint8_t src_addr_size;
DEBUGASSERT(iob->io_pktlen > 0);
/* Transfer that buffered data from the I/O buffer chain into
* the user buffer.
*/
recvlen = iob_copyout(&src_addr_size, iob, sizeof(uint8_t), 0);
if (recvlen != sizeof(uint8_t))
{
goto out;
}
if (0
#ifdef CONFIG_NET_IPv6
|| src_addr_size == sizeof(struct sockaddr_in6)
#endif
#ifdef CONFIG_NET_IPv4
|| src_addr_size == sizeof(struct sockaddr_in)
#endif
)
{
if (pstate->ir_from)
{
socklen_t len = *pstate->ir_fromlen;
len = (socklen_t)src_addr_size > len ? len : (socklen_t)src_addr_size;
recvlen = iob_copyout((FAR uint8_t *)pstate->ir_from, iob,
len, sizeof(uint8_t));
if (recvlen != len)
{
goto out;
}
}
}
if (pstate->ir_buflen > 0)
{
recvlen = iob_copyout(pstate->ir_buffer, iob, pstate->ir_buflen,
src_addr_size + sizeof(uint8_t));
ninfo("Received %d bytes (of %d)\n", recvlen, iob->io_pktlen);
/* Update the accumulated size of the data read */
pstate->ir_recvlen = recvlen;
pstate->ir_buffer += recvlen;
pstate->ir_buflen -= recvlen;
}
else
{
pstate->ir_recvlen = 0;
}
out:
/* Remove the I/O buffer chain from the head of the read-ahead
* buffer queue.
*/
tmp = iob_remove_queue(&conn->readahead);
DEBUGASSERT(tmp == iob);
UNUSED(tmp);
/* And free the I/O buffer chain */
(void)iob_free_chain(iob);
}
}
#endif
/****************************************************************************
* Name: inet_recvfrom_timeout
*
* Description:
* Check for recvfrom timeout.
*
* Input Parameters:
* pstate recvfrom state structure
*
* Returned Value:
* TRUE:timeout FALSE:no timeout
*
* Assumptions:
* The network is locked.
*
****************************************************************************/
#if defined(NET_UDP_HAVE_STACK) || defined(NET_TCP_HAVE_STACK)
#ifdef CONFIG_NET_SOCKOPTS
static int inet_recvfrom_timeout(struct inet_recvfrom_s *pstate)
{
FAR struct socket *psock = 0;
socktimeo_t timeo = 0;
/* Check for a timeout configured via setsockopts(SO_RCVTIMEO). If none...
* we well let the read hang forever (except for the special case below).
*/
/* Get the socket reference from the private data */
psock = pstate->ir_sock;
if (psock)
{
/* Recover the timeout value (zero if no timeout) */
timeo = psock->s_rcvtimeo;
}
/* Use a fixed, configurable delay under the following circumstances:
*
* 1) This delay function has been enabled with CONFIG_NET_TCP_RECVDELAY > 0
* 2) Some data has already been received from the socket. Since this can
* only be true for a TCP/IP socket, this logic applies only to TCP/IP
* sockets. And either
* 3) There is no configured receive timeout, or
* 4) The configured receive timeout is greater than than the delay
*/
#if CONFIG_NET_TCP_RECVDELAY > 0
if ((timeo == 0 || timeo > CONFIG_NET_TCP_RECVDELAY) &&
pstate->ir_recvlen > 0)
{
/* Use the configured timeout */
timeo = CONFIG_NET_TCP_RECVDELAY;
}
#endif
/* Is there an effective timeout? */
if (timeo)
{
/* Yes.. Check if the timeout has elapsed */
return net_timeo(pstate->ir_starttime, timeo);
}
/* No timeout -- hang forever waiting for data. */
return FALSE;
}
#endif /* CONFIG_NET_SOCKOPTS */
#endif /* NET_UDP_HAVE_STACK || NET_TCP_HAVE_STACK */
/****************************************************************************
* Name: inet_tcp_sender
*
* Description:
* Getting the sender's address from the UDP packet
*
* Input Parameters:
* dev - The device driver data structure
* pstate - the recvfrom state structure
*
* Returned Value:
* None
*
* Assumptions:
* The network is locked
*
****************************************************************************/
#ifdef NET_TCP_HAVE_STACK
static inline void inet_tcp_sender(FAR struct net_driver_s *dev,
FAR struct inet_recvfrom_s *pstate)
{
/* Get the family from the packet type, IP address from the IP header, and
* the port number from the TCP header.
*/
#ifdef CONFIG_NET_IPv6
#ifdef CONFIG_NET_IPv4
if (IFF_IS_IPv6(dev->d_flags))
#endif
{
FAR struct sockaddr_in6 *infrom =
(FAR struct sockaddr_in6 *)pstate->ir_from;
if (infrom)
{
FAR struct tcp_hdr_s *tcp = TCPIPv6BUF;
FAR struct ipv6_hdr_s *ipv6 = IPv6BUF;
infrom->sin6_family = AF_INET6;
infrom->sin6_port = tcp->srcport;
net_ipv6addr_copy(infrom->sin6_addr.s6_addr, ipv6->srcipaddr);
}
}
#endif /* CONFIG_NET_IPv6 */
#ifdef CONFIG_NET_IPv4
#ifdef CONFIG_NET_IPv6
else
#endif
{
FAR struct sockaddr_in *infrom =
(FAR struct sockaddr_in *)pstate->ir_from;
if (infrom)
{
FAR struct tcp_hdr_s *tcp = TCPIPv4BUF;
FAR struct ipv4_hdr_s *ipv4 = IPv4BUF;
infrom->sin_family = AF_INET;
infrom->sin_port = tcp->srcport;
net_ipv4addr_copy(infrom->sin_addr.s_addr,
net_ip4addr_conv32(ipv4->srcipaddr));
}
}
#endif /* CONFIG_NET_IPv4 */
}
#endif /* NET_TCP_HAVE_STACK */
/****************************************************************************
* Name: inet_tcp_eventhandler
*
* Description:
* This function is called with the network locked to perform the actual
* TCP receive operation via by the lower, device interfacing layer.
*
* Input Parameters:
* dev The structure of the network driver that generated the event.
* pvconn The connection structure associated with the socket
* flags Set of events describing why the callback was invoked
*
* Returned Value:
* None
*
* Assumptions:
* The network is locked.
*
****************************************************************************/
#ifdef NET_TCP_HAVE_STACK
static uint16_t inet_tcp_eventhandler(FAR struct net_driver_s *dev,
FAR void *pvconn, FAR void *pvpriv,
uint16_t flags)
{
FAR struct inet_recvfrom_s *pstate = (struct inet_recvfrom_s *)pvpriv;
#if 0 /* REVISIT: The assertion fires. Why? */
FAR struct tcp_conn_s *conn = (FAR struct tcp_conn_s *)pvconn;
/* The TCP socket is connected and, hence, should be bound to a device.
* Make sure that the polling device is the own that we are bound to.
*/
DEBUGASSERT(conn->dev == NULL || conn->dev == dev);
if (conn->dev != NULL && conn->dev != dev)
{
return flags;
}
#endif
ninfo("flags: %04x\n", flags);
/* 'priv' might be null in some race conditions (?) */
if (pstate)
{
/* If new data is available, then complete the read action. */
if ((flags & TCP_NEWDATA) != 0)
{
/* Copy the data from the packet (saving any unused bytes from the
* packet in the read-ahead buffer).
*/
inet_tcp_newdata(dev, pstate);
/* Save the sender's address in the caller's 'from' location */
inet_tcp_sender(dev, pstate);
/* Indicate that the data has been consumed and that an ACK
* should be sent.
*/
flags = (flags & ~TCP_NEWDATA) | TCP_SNDACK;
/* Check for transfer complete. We will consider the transfer
* complete in own of two different ways, depending on the setting
* of CONFIG_NET_TCP_RECVDELAY.
*
* 1) If CONFIG_NET_TCP_RECVDELAY == 0 then we will consider the
* TCP/IP transfer complete as soon as any data has been received.
* This is safe because if any additional data is received, it
* will be retained in the TCP/IP read-ahead buffer until the
* next receive is performed.
* 2) CONFIG_NET_TCP_RECVDELAY > 0 may be set to wait a little
* bit to determine if more data will be received. You might
* do this if read-ahead buffering is disabled and we want to
* minimize the loss of back-to-back packets. In this case,
* the transfer is complete when either a) the entire user buffer
* is full or 2) when the receive timeout occurs (below).
*/
#if CONFIG_NET_TCP_RECVDELAY > 0
if (pstate->ir_buflen == 0)
#else
if (pstate->ir_recvlen > 0)
#endif
{
ninfo("TCP resume\n");
/* The TCP receive buffer is non-empty. Return now and don't
* allow any further TCP call backs.
*/
pstate->ir_cb->flags = 0;
pstate->ir_cb->priv = NULL;
pstate->ir_cb->event = NULL;
/* Wake up the waiting thread, returning the number of bytes
* actually read.
*/
nxsem_post(&pstate->ir_sem);
}
#ifdef CONFIG_NET_SOCKOPTS
/* Reset the timeout. We will want a short timeout to terminate
* the TCP receive.
*/
pstate->ir_starttime = clock_systimer();
#endif
}
/* Check for a loss of connection.
*
* TCP_DISCONN_EVENTS:
* TCP_CLOSE: The remote host has closed the connection
* TCP_ABORT: The remote host has aborted the connection
* TCP_TIMEDOUT: Connection aborted due to too many retransmissions.
* NETDEV_DOWN: The network device went down
*/
else if ((flags & TCP_DISCONN_EVENTS) != 0)
{
FAR struct socket *psock = pstate->ir_sock;
nwarn("WARNING: Lost connection\n");
/* We could get here recursively through the callback actions of
* tcp_lost_connection(). So don't repeat that action if we have
* already been disconnected.
*/
DEBUGASSERT(psock != NULL);
if (_SS_ISCONNECTED(psock->s_flags))
{
/* Handle loss-of-connection event */
tcp_lost_connection(psock, pstate->ir_cb, flags);
}
/* Check if the peer gracefully closed the connection. */
if ((flags & TCP_CLOSE) != 0)
{
/* This case should always return success (zero)! The value of
* ir_recvlen, if zero, will indicate that the connection was
* gracefully closed.
*/
pstate->ir_result = 0;
}
else
{
/* If no data has been received, then return ENOTCONN.
* Otherwise, let this return success. The failure will
* be reported the next time that recv[from]() is called.
*/
#if CONFIG_NET_TCP_RECVDELAY > 0
if (pstate->ir_recvlen > 0)
{
pstate->ir_result = 0;
}
else
{
pstate->ir_result = -ENOTCONN;
}
#else
pstate->ir_result = -ENOTCONN;
#endif
}
/* Wake up the waiting thread */
nxsem_post(&pstate->ir_sem);
}
#ifdef CONFIG_NET_SOCKOPTS
/* No data has been received -- this is some other event... probably a
* poll -- check for a timeout.
*/
else if (inet_recvfrom_timeout(pstate))
{
/* Yes.. the timeout has elapsed... do not allow any further
* callbacks
*/
ninfo("TCP timeout\n");
pstate->ir_cb->flags = 0;
pstate->ir_cb->priv = NULL;
pstate->ir_cb->event = NULL;
/* Report an error only if no data has been received. (If
* CONFIG_NET_TCP_RECVDELAY then ir_recvlen should always be
* less than or equal to zero).
*/
#if CONFIG_NET_TCP_RECVDELAY > 0
if (pstate->ir_recvlen <= 0)
#endif
{
/* Report the timeout error */
pstate->ir_result = -EAGAIN;
}
/* Wake up the waiting thread, returning either the error -EAGAIN
* that signals the timeout event or the data received up to
* the point that the timeout occurred (no error).
*/
nxsem_post(&pstate->ir_sem);
}
#endif /* CONFIG_NET_SOCKOPTS */
}
return flags;
}
#endif /* NET_TCP_HAVE_STACK */
/****************************************************************************
* Name: inet_udp_sender
*
* Description:
* Getting the sender's address from the UDP packet
*
* Input Parameters:
* dev - The device driver data structure
* pstate - the recvfrom state structure
*
* Returned Value:
* None
*
* Assumptions:
* The network is locked.
*
****************************************************************************/
#ifdef NET_UDP_HAVE_STACK
static inline void inet_udp_sender(struct net_driver_s *dev, struct inet_recvfrom_s *pstate)
{
/* Get the family from the packet type, IP address from the IP header, and
* the port number from the UDP header.
*/
#ifdef CONFIG_NET_IPv6
#ifdef CONFIG_NET_IPv4
if (IFF_IS_IPv6(dev->d_flags))
#endif
{
FAR struct sockaddr_in6 *infrom =
(FAR struct sockaddr_in6 *)pstate->ir_from;
FAR socklen_t *fromlen = pstate->ir_fromlen;
if (infrom)
{
FAR struct udp_hdr_s *udp = UDPIPv6BUF;
FAR struct ipv6_hdr_s *ipv6 = IPv6BUF;
infrom->sin6_family = AF_INET6;
infrom->sin6_port = udp->srcport;
*fromlen = sizeof(struct sockaddr_in6);
net_ipv6addr_copy(infrom->sin6_addr.s6_addr, ipv6->srcipaddr);
}
}
#endif /* CONFIG_NET_IPv6 */
#ifdef CONFIG_NET_IPv4
#ifdef CONFIG_NET_IPv6
else
#endif
{
FAR struct sockaddr_in *infrom =
(FAR struct sockaddr_in *)pstate->ir_from;
if (infrom)
{
#ifdef CONFIG_NET_IPv6
FAR struct udp_conn_s *conn =
(FAR struct udp_conn_s *)pstate->ir_sock->s_conn;
/* Hybrid dual-stack IPv6/IPv4 implementations recognize a special
* class of addresses, the IPv4-mapped IPv6 addresses.
*/
if (conn->domain == PF_INET6)
{
FAR struct sockaddr_in6 *infrom6 = (FAR struct sockaddr_in6 *)infrom;
FAR socklen_t *fromlen = pstate->ir_fromlen;
FAR struct udp_hdr_s *udp = UDPIPv6BUF;
FAR struct ipv6_hdr_s *ipv6 = IPv6BUF;
in_addr_t ipv4addr;
/* Encode the IPv4 address as an IPv4-mapped IPv6 address */
infrom6->sin6_family = AF_INET6;
infrom6->sin6_port = udp->srcport;
*fromlen = sizeof(struct sockaddr_in6);
ipv4addr = net_ip4addr_conv32(ipv6->srcipaddr);
ip6_map_ipv4addr(ipv4addr, infrom6->sin6_addr.s6_addr16);
}
else
#endif
{
FAR struct udp_hdr_s *udp = UDPIPv4BUF;
FAR struct ipv4_hdr_s *ipv4 = IPv4BUF;
infrom->sin_family = AF_INET;
infrom->sin_port = udp->srcport;
net_ipv4addr_copy(infrom->sin_addr.s_addr,
net_ip4addr_conv32(ipv4->srcipaddr));
}
}
}
#endif /* CONFIG_NET_IPv4 */
}
#endif /* NET_UDP_HAVE_STACK */
/****************************************************************************
* Name: inet_udp_terminate
*
* Description:
* Terminate the UDP transfer.
*
* Input Parameters:
* pstate - The recvfrom state structure
* result - The result of the operation
*
* Returned Value:
* None
*
****************************************************************************/
#ifdef NET_UDP_HAVE_STACK
static void inet_udp_terminate(FAR struct inet_recvfrom_s *pstate, int result)
{
/* Don't allow any further UDP call backs. */
pstate->ir_cb->flags = 0;
pstate->ir_cb->priv = NULL;
pstate->ir_cb->event = NULL;
/* Save the result of the transfer */
pstate->ir_result = result;
/* Wake up the waiting thread, returning the number of bytes
* actually read.
*/
nxsem_post(&pstate->ir_sem);
}
#endif /* NET_UDP_HAVE_STACK */
/****************************************************************************
* Name: inet_udp_eventhandler
*
* Description:
* This function is called with the network locked to perform the actual
* UDP receive operation via by the lower, device interfacing layer.
*
* Input Parameters:
* dev The structure of the network driver that generated the event.
* pvconn The connection structure associated with the socket
* flags Set of events describing why the callback was invoked
*
* Returned Value:
* None
*
* Assumptions:
* The network is locked.
*
****************************************************************************/
#ifdef NET_UDP_HAVE_STACK
static uint16_t inet_udp_eventhandler(FAR struct net_driver_s *dev,
FAR void *pvconn, FAR void *pvpriv,
uint16_t flags)
{
FAR struct inet_recvfrom_s *pstate = (FAR struct inet_recvfrom_s *)pvpriv;
ninfo("flags: %04x\n", flags);
/* 'priv' might be null in some race conditions (?) */
if (pstate)
{
/* If the network device has gone down, then we will have terminate
* the wait now with an error.
*/
if ((flags & NETDEV_DOWN) != 0)
{
/* Terminate the transfer with an error. */
nerr("ERROR: Network is down\n");
inet_udp_terminate(pstate, -ENETUNREACH);
}
/* If new data is available, then complete the read action. */
else if ((flags & UDP_NEWDATA) != 0)
{
/* Copy the data from the packet */
inet_udp_newdata(dev, pstate);
/* We are finished. */
ninfo("UDP done\n");
/* Save the sender's address in the caller's 'from' location */
inet_udp_sender(dev, pstate);
/* Don't allow any further UDP call backs. */
inet_udp_terminate(pstate, OK);
/* Indicate that the data has been consumed */
flags &= ~UDP_NEWDATA;
}
#ifdef CONFIG_NET_SOCKOPTS
/* No data has been received -- this is some other event... probably a
* poll -- check for a timeout.
*/
else if (inet_recvfrom_timeout(pstate))
{
/* Yes.. the timeout has elapsed... do not allow any further
* callbacks
*/
nerr("ERROR: UDP timeout\n");
/* Terminate the transfer with an -EAGAIN error */
inet_udp_terminate(pstate, -EAGAIN);
}
#endif /* CONFIG_NET_SOCKOPTS */
}
return flags;
}
#endif /* NET_UDP_HAVE_STACK */
/****************************************************************************
* Name: inet_recvfrom_initialize
*
* Description:
* Initialize the state structure
*
* Input Parameters:
* psock Pointer to the socket structure for the socket
* buf Buffer to receive data
* len Length of buffer
* pstate A pointer to the state structure to be initialized
*
* Returned Value:
* None
*
* Assumptions:
*
****************************************************************************/
#if defined(NET_UDP_HAVE_STACK) || defined(NET_TCP_HAVE_STACK)
static void inet_recvfrom_initialize(FAR struct socket *psock, FAR void *buf,
size_t len, FAR struct sockaddr *infrom,
FAR socklen_t *fromlen,
FAR struct inet_recvfrom_s *pstate)
{
/* Initialize the state structure. */
memset(pstate, 0, sizeof(struct inet_recvfrom_s));
/* This semaphore is used for signaling and, hence, should not have
* priority inheritance enabled.
*/
(void)nxsem_init(&pstate->ir_sem, 0, 0); /* Doesn't really fail */
(void)nxsem_setprotocol(&pstate->ir_sem, SEM_PRIO_NONE);
pstate->ir_buflen = len;
pstate->ir_buffer = buf;
pstate->ir_from = infrom;
pstate->ir_fromlen = fromlen;
/* Set up the start time for the timeout */
pstate->ir_sock = psock;
#ifdef CONFIG_NET_SOCKOPTS
pstate->ir_starttime = clock_systimer();
#endif
}
/* The only un-initialization that has to be performed is destroying the
* semaphore.
*/
#define inet_recvfrom_uninitialize(s) nxsem_destroy(&(s)->ir_sem)
#endif /* NET_UDP_HAVE_STACK || NET_TCP_HAVE_STACK */
/****************************************************************************
* Name: inet_recvfrom_result
*
* Description:
* Evaluate the result of the recv operations
*
* Input Parameters:
* result The result of the net_lockedwait operation (may indicate EINTR)
* pstate A pointer to the state structure to be initialized
*
* Returned Value:
* The result of the recv operation with errno set appropriately
*
* Assumptions:
*
****************************************************************************/
#if defined(NET_UDP_HAVE_STACK) || defined(NET_TCP_HAVE_STACK)
static ssize_t inet_recvfrom_result(int result, struct inet_recvfrom_s *pstate)
{
/* Check for a error/timeout detected by the event handler. Errors are
* signaled by negative errno values for the rcv length
*/
if (pstate->ir_result < 0)
{
/* This might return EAGAIN on a timeout or ENOTCONN on loss of
* connection (TCP only)
*/
return pstate->ir_result;
}
/* If net_lockedwait failed, then we were probably reawakened by a signal. In
* this case, net_lockedwait will have returned negated errno appropriately.
*/
if (result < 0)
{
return result;
}
return pstate->ir_recvlen;
}
#endif /* NET_UDP_HAVE_STACK || NET_TCP_HAVE_STACK */
/****************************************************************************
* Name: inet_udp_recvfrom
*
* Description:
* Perform the recvfrom operation for a UDP SOCK_DGRAM
*
* Input Parameters:
* psock Pointer to the socket structure for the SOCK_DRAM socket
* buf Buffer to receive data
* len Length of buffer
* from INET address of source (may be NULL)
*
* Returned Value:
* On success, returns the number of characters received. On error,
* -errno is returned (see recvfrom for list of errnos).
*
* Assumptions:
*
****************************************************************************/
#ifdef NET_UDP_HAVE_STACK
static ssize_t inet_udp_recvfrom(FAR struct socket *psock, FAR void *buf, size_t len,
FAR struct sockaddr *from, FAR socklen_t *fromlen)
{
FAR struct udp_conn_s *conn = (FAR struct udp_conn_s *)psock->s_conn;
FAR struct net_driver_s *dev;
struct inet_recvfrom_s state;
int ret;
/* Perform the UDP recvfrom() operation */
/* Initialize the state structure. This is done with the network locked
* because we don't want anything to happen until we are ready.
*/
net_lock();
inet_recvfrom_initialize(psock, buf, len, from, fromlen, &state);
#ifdef CONFIG_NET_UDP_READAHEAD
/* Copy the read-ahead data from the packet */
inet_udp_readahead(&state);
/* The default return value is the number of bytes that we just copied
* into the user buffer. We will return this if the socket has become
* disconnected or if the user request was completely satisfied with
* data from the readahead buffers.
*/
ret = state.ir_recvlen;
#else
/* Otherwise, the default return value of zero is used (only for the case
* where len == state.ir_buflen is zero).
*/
ret = 0;
#endif
#ifdef CONFIG_NET_UDP_READAHEAD
/* Handle non-blocking UDP sockets */
if (_SS_ISNONBLOCK(psock->s_flags))
{
/* Return the number of bytes read from the read-ahead buffer if
* something was received (already in 'ret'); EAGAIN if not.
*/
if (ret < 0)
{
/* Nothing was received */
ret = -EAGAIN;
}
}
/* It is okay to block if we need to. If there is space to receive anything
* more, then we will wait to receive the data. Otherwise return the number
* of bytes read from the read-ahead buffer (already in 'ret').
*
* NOTE: that inet_udp_readahead() may set state.ir_recvlen == -1.
*/
else if (state.ir_recvlen <= 0)
#endif
{
/* Get the device that will handle the packet transfers. This may be
* NULL if the UDP socket is bound to INADDR_ANY. In that case, no
* NETDEV_DOWN notifications will be received.
*/
dev = udp_find_laddr_device(conn);
/* Set up the callback in the connection */
state.ir_cb = udp_callback_alloc(dev, conn);
if (state.ir_cb)
{
/* Set up the callback in the connection */
state.ir_cb->flags = (UDP_NEWDATA | UDP_POLL | NETDEV_DOWN);
state.ir_cb->priv = (FAR void *)&state;
state.ir_cb->event = inet_udp_eventhandler;
/* Wait for either the receive to complete or for an error/timeout
* to occur. net_lockedwait will also terminate if a signal is
* received.
*/
ret = net_lockedwait(&state. ir_sem);
/* Make sure that no further events are processed */
udp_callback_free(dev, conn, state.ir_cb);
ret = inet_recvfrom_result(ret, &state);
}
else
{
ret = -EBUSY;
}
}
net_unlock();
inet_recvfrom_uninitialize(&state);
return ret;
}
#endif /* NET_UDP_HAVE_STACK */
/****************************************************************************
* Name: inet_tcp_recvfrom
*
* Description:
* Perform the recvfrom operation for a TCP/IP SOCK_STREAM
*
* Input Parameters:
* psock Pointer to the socket structure for the SOCK_DRAM socket
* buf Buffer to receive data
* len Length of buffer
* from INET address of source (may be NULL)
*
* Returned Value:
* On success, returns the number of characters received. On error,
* -errno is returned (see recvfrom for list of errnos).
*
* Assumptions:
*
****************************************************************************/
#ifdef NET_TCP_HAVE_STACK
static ssize_t inet_tcp_recvfrom(FAR struct socket *psock, FAR void *buf, size_t len,
FAR struct sockaddr *from, FAR socklen_t *fromlen)
{
struct inet_recvfrom_s state;
int ret;
/* Initialize the state structure. This is done with the network locked
* because we don't want anything to happen until we are ready.
*/
net_lock();
inet_recvfrom_initialize(psock, buf, len, from, fromlen, &state);
/* Handle any any TCP data already buffered in a read-ahead buffer. NOTE
* that there may be read-ahead data to be retrieved even after the
* socket has been disconnected.
*/
#ifdef CONFIG_NET_TCP_READAHEAD
inet_tcp_readahead(&state);
/* The default return value is the number of bytes that we just copied
* into the user buffer. We will return this if the socket has become
* disconnected or if the user request was completely satisfied with
* data from the readahead buffers.
*/
ret = state.ir_recvlen;
#else
/* Otherwise, the default return value of zero is used (only for the case
* where len == state.ir_buflen is zero).
*/
ret = 0;
#endif
/* Verify that the SOCK_STREAM has been and still is connected */
if (!_SS_ISCONNECTED(psock->s_flags))
{
/* Was any data transferred from the readahead buffer after we were
* disconnected? If so, then return the number of bytes received. We
* will wait to return end disconnection indications the next time that
* recvfrom() is called.
*
* If no data was received (i.e., ret == 0 -- it will not be negative)
* and the connection was gracefully closed by the remote peer, then return
* success. If ir_recvlen is zero, the caller of recvfrom() will get an
* end-of-file indication.
*/
#ifdef CONFIG_NET_TCP_READAHEAD
if (ret <= 0 && !_SS_ISCLOSED(psock->s_flags))
#else
if (!_SS_ISCLOSED(psock->s_flags))
#endif
{
/* Nothing was previously received from the readahead buffers.
* The SOCK_STREAM must be (re-)connected in order to receive any
* additional data.
*/
ret = -ENOTCONN;
}
}
/* In general, this implementation will not support non-blocking socket
* operations... except in a few cases: Here for TCP receive with read-ahead
* enabled. If this socket is configured as non-blocking then return EAGAIN
* if no data was obtained from the read-ahead buffers.
*/
else
#ifdef CONFIG_NET_TCP_READAHEAD
if (_SS_ISNONBLOCK(psock->s_flags))
{
/* Return the number of bytes read from the read-ahead buffer if
* something was received (already in 'ret'); EAGAIN if not.
*/
if (ret <= 0)
{
/* Nothing was received */
ret = -EAGAIN;
}
}
/* It is okay to block if we need to. If there is space to receive anything
* more, then we will wait to receive the data. Otherwise return the number
* of bytes read from the read-ahead buffer (already in 'ret').
*/
else
#endif
/* We get here when we we decide that we need to setup the wait for incoming
* TCP/IP data. Just a few more conditions to check:
*
* 1) Make sure thet there is buffer space to receive additional data
* (state.ir_buflen > 0). This could be zero, for example, if read-ahead
* buffering was enabled and we filled the user buffer with data from
* the read-ahead buffers. And
* 2) if read-ahead buffering is enabled (CONFIG_NET_TCP_READAHEAD)
* and delay logic is disabled (CONFIG_NET_TCP_RECVDELAY == 0), then we
* not want to wait if we already obtained some data from the read-ahead
* buffer. In that case, return now with what we have (don't want for more
* because there may be no timeout).
*/
#if CONFIG_NET_TCP_RECVDELAY == 0 && defined(CONFIG_NET_TCP_READAHEAD)
if (state.ir_recvlen == 0 && state.ir_buflen > 0)
#else
if (state.ir_buflen > 0)
#endif
{
FAR struct tcp_conn_s *conn = (FAR struct tcp_conn_s *)psock->s_conn;
/* Set up the callback in the connection */
state.ir_cb = tcp_callback_alloc(conn);
if (state.ir_cb)
{
state.ir_cb->flags = (TCP_NEWDATA | TCP_POLL | TCP_DISCONN_EVENTS);
state.ir_cb->priv = (FAR void *)&state;
state.ir_cb->event = inet_tcp_eventhandler;
/* Wait for either the receive to complete or for an error/timeout
* to occur. net_lockedwait will also terminate if a signal isi
* received.
*/
ret = net_lockedwait(&state.ir_sem);
/* Make sure that no further events are processed */
tcp_callback_free(conn, state.ir_cb);
ret = inet_recvfrom_result(ret, &state);
}
else
{
ret = -EBUSY;
}
}
net_unlock();
inet_recvfrom_uninitialize(&state);
return (ssize_t)ret;
}
#endif /* NET_TCP_HAVE_STACK */
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: inet_recvfrom
*
* Description:
* Implements the socket recvfrom interface for the case of the AF_INET
* and AF_INET6 address families. inet_recvfrom() receives messages from
* a socket, and may be used to receive data on a socket whether or not it
* is connection-oriented.
*
* If 'from' is not NULL, and the underlying protocol provides the source
* address, this source address is filled in. The argument 'fromlen' is
* initialized to the size of the buffer associated with from, and
* modified on return to indicate the actual size of the address stored
* there.
*
* Input Parameters:
* psock A pointer to a NuttX-specific, internal socket structure
* buf Buffer to receive data
* len Length of buffer
* flags Receive flags
* from Address of source (may be NULL)
* fromlen The length of the address structure
*
* Returned Value:
* On success, returns the number of characters received. If no data is
* available to be received and the peer has performed an orderly shutdown,
* recv() will return 0. Otherwise, on errors, a negated errno value is
* returned (see recvfrom() for the list of appropriate error values).
*
****************************************************************************/
ssize_t inet_recvfrom(FAR struct socket *psock, FAR void *buf, size_t len,
int flags, FAR struct sockaddr *from,
FAR socklen_t *fromlen)
{
ssize_t ret;
/* If a 'from' address has been provided, verify that it is large
* enough to hold this address family.
*/
if (from)
{
socklen_t minlen;
/* Get the minimum socket length */
switch (psock->s_domain)
{
#ifdef CONFIG_NET_IPv4
case PF_INET:
{
minlen = sizeof(struct sockaddr_in);
}
break;
#endif
#ifdef CONFIG_NET_IPv6
case PF_INET6:
{
minlen = sizeof(struct sockaddr_in6);
}
break;
#endif
default:
DEBUGPANIC();
return -EINVAL;
}
if (*fromlen < minlen)
{
return -EINVAL;
}
}
/* Read from the network interface driver buffer */
/* Or perform the TCP/IP or UDP recv() operation */
switch (psock->s_type)
{
#ifdef CONFIG_NET_TCP
case SOCK_STREAM:
{
#ifdef NET_TCP_HAVE_STACK
ret = inet_tcp_recvfrom(psock, buf, len, from, fromlen);
#else
ret = -ENOSYS;
#endif
}
break;
#endif /* CONFIG_NET_TCP */
#ifdef CONFIG_NET_UDP
case SOCK_DGRAM:
{
#ifdef NET_UDP_HAVE_STACK
ret = inet_udp_recvfrom(psock, buf, len, from, fromlen);
#else
ret = -ENOSYS;
#endif
}
break;
#endif /* CONFIG_NET_UDP */
default:
{
nerr("ERROR: Unsupported socket type: %d\n", psock->s_type);
ret = -ENOSYS;
}
break;
}
return ret;
}
#endif /* CONFIG_NET */
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