Sockets: Initial steps to adde a socket interface to the networking. Each address family will have an interface that describes how to perform socket operations on that address family. Currently only a couple of methods are defined in the table as a proof of concept. More to come. Currently there are only tables for the INET/INET6 family, the Unix LOCAL family, and the raw PACKET family. Hopefully there will be AF_IEEE802154 and AF_BLUETOOTH comming down the pike.

include/nuttx/net/net.h

@@ -94,11 +94,27 @@ typedef uint16_t sockopt_t;
 
 typedef uint16_t socktimeo_t;
 
+/* This callbacks are socket operations that may be performed on a socket of
+ * a given address family.
+ */
+
+struct socket;  /* Forward reference */
+
+struct sock_intf_s
+{
+  CODE int (*si_setup)(FAR struct socket *psock, int protocol);
+  CODE ssize_t (*si_send)(FAR struct socket *psock, FAR const void *buf,
+                 size_t len, int flags);
+  CODE ssize_t (*si_sendto)(FAR struct socket *psock, FAR const void *buf,
+                 size_t len, int flags, FAR const struct sockaddr *to,
+                 socklen_t tolen);
+};
+
 /* This is the internal representation of a socket reference by a file
  * descriptor.
  */
 
-struct devif_callback_s;     /* Forward reference */
+struct devif_callback_s;  /* Forward reference */
 
 struct socket
 {
@@ -120,6 +136,10 @@ struct socket
 
   FAR void     *s_conn;      /* Connection: struct tcp_conn_s or udp_conn_s */
 
+  /* Socket interface */
+
+  FAR const struct sock_intf_s *s_sockif;
+
 #ifdef CONFIG_NET_TCP_WRITE_BUFFERS
   /* Callback instance for TCP send */
 

net/local/Make.defs

@@ -39,6 +39,7 @@ ifeq ($(CONFIG_NET_LOCAL),y)
 
 NET_CSRCS += local_conn.c local_release.c local_bind.c local_fifo.c
 NET_CSRCS += local_recvfrom.c local_sendpacket.c local_recvutils.c
+NET_CSRCS += local_sockif.c
 
 ifeq ($(CONFIG_NET_LOCAL_STREAM),y)
 NET_CSRCS += local_connect.c local_listen.c local_accept.c local_send.c

net/local/local.h

@@ -51,6 +51,8 @@
 #include <stdint.h>
 #include <poll.h>
 
+#include <nuttx/net/net.h>
+
 #ifdef CONFIG_NET_LOCAL
 
 /****************************************************************************
@@ -77,6 +79,7 @@
 /****************************************************************************
  * Public Type Definitions
  ****************************************************************************/
+
 /* Local, Unix domain socket types */
 
 enum local_type_e
@@ -204,6 +207,10 @@ extern "C"
 #  define EXTERN extern
 #endif
 
+/* The local socket interface */
+
+EXTERN const struct sock_intf_s g_local_sockif;
+
 #ifdef CONFIG_NET_LOCAL_STREAM
 /* A list of all SOCK_STREAM listener connections */
 

net/local/local_sockif.c

@@ -0,0 +1,305 @@
+/****************************************************************************
+ * net/local/local_sockif.c
+ *
+ *   Copyright (C) 2017 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>
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <assert.h>
+#include <errno.h>
+#include <debug.h>
+
+#include <netinet/in.h>
+
+#include <nuttx/net/net.h>
+
+#include "local/local.h"
+
+#ifdef CONFIG_NET_LOCAL
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+static ssize_t local_setup(FAR struct socket *psock, int protocol);
+static ssize_t local_send(FAR struct socket *psock, FAR const void *buf,
+                 size_t len, int flags);
+static ssize_t local_sendto(FAR struct socket *psock, FAR const void *buf,
+                 size_t len, int flags, FAR const struct sockaddr *to,
+                 socklen_t tolen);
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+const struct sock_intf_s g_local_sockif =
+{
+  local_setup,   /* si_setup */
+  local_send,    /* si_send */
+  local_sendto,  /* si_sendto */
+};
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: local_sockif_alloc
+ *
+ * Description:
+ *   Allocate and attach a local, Unix domain connection structure.
+ *
+ ****************************************************************************/
+
+static int local_sockif_alloc(FAR struct socket *psock)
+{
+  /* Allocate the local connection structure */
+
+  FAR struct local_conn_s *conn = local_alloc();
+  if (conn == NULL)
+    {
+      /* Failed to reserve a connection structure */
+
+      return -ENOMEM;
+    }
+
+  /* Set the reference count on the connection structure.  This reference
+   * count will be incremented only if the socket is dup'ed
+   */
+
+  DEBUGASSERT(conn->lc_crefs == 0);
+  conn->lc_crefs = 1;
+
+  /* Save the pre-allocated connection in the socket structure */
+
+  psock->s_conn = conn;
+  return OK;
+}
+
+/****************************************************************************
+ * Name: local_setup
+ *
+ * Description:
+ *   Called for socket() to verify that the provided socket type and
+ *   protocol are usable by this address family.  Perform any family-
+ *   specific socket fields.
+ *
+ * Parameters:
+ *   psock    A pointer to a user allocated socket structure to be initialized.
+ *   protocol (see sys/socket.h)
+ *
+ * Returned Value:
+ *   Zero (OK) is returned on success.  Otherwise, a negater errno value is
+ *   returned.
+ *
+ ****************************************************************************/
+
+static int local_setup(FAR struct socket *psock, int protocol)
+{
+  /* Allocate the appropriate connection structure.  This reserves the
+   * the connection structure is is unallocated at this point.  It will
+   * not actually be initialized until the socket is connected.
+   *
+   * Only SOCK_STREAM and SOCK_DGRAM and possible SOCK_RAW are supported.
+   */
+
+  switch (psock->s_type)
+    {
+#ifdef CONFIG_NET_TCP
+      case SOCK_STREAM:
+        if (protocol != 0 && protocol != IPPROTO_TCP)
+          {
+            return -EPROTONOSUPPORT;
+          }
+
+        /* Allocate and attach the local connection structure */
+
+        return local_sockif_alloc(psock);
+#endif /* CONFIG_NET_TCP */
+
+#ifdef CONFIG_NET_UDP
+      case SOCK_DGRAM:
+        if (protocol != 0 && protocol != IPPROTO_UDP)
+          {
+            return -EPROTONOSUPPORT;
+          }
+
+        /* Allocate and attach the local connection structure */
+
+        return local_sockif_alloc(psock);
+#endif /* CONFIG_NET_UDP */
+
+      default:
+        return -EPROTONOSUPPORT;
+    }
+}
+
+/****************************************************************************
+ * Name: local_send
+ *
+ * Description:
+ *   Implements the send() operation for the case of the local, Unix socket.
+ *
+ * Parameters:
+ *   psock    An instance of the internal socket structure.
+ *   buf      Data to send
+ *   len      Length of data to send
+ *   flags    Send flags
+ *
+ * Returned Value:
+ *   On success, returns the number of characters sent.  On  error, -1 is
+ *   returned, and errno is set appropriately (see send() for the list of
+ *   appropriate errors values.
+ *
+ ****************************************************************************/
+
+static ssize_t local_send(FAR struct socket *psock, FAR const void *buf,
+                          size_t len, int flags)
+{
+  ssize_t ret;
+
+  switch (psock->s_type)
+    {
+#ifdef CONFIG_NET_TCP
+      case SOCK_STREAM:
+        {
+          /* Local TCP packet send */
+
+          ret = psock_local_send(psock, buf, len, flags);
+        }
+        break;
+#endif /* CONFIG_NET_TCP */
+
+#ifdef CONFIG_NET_UDP
+      case SOCK_DGRAM:
+        {
+          /* Local UDP packet send */
+#warning Missing logic
+          ret = -ENOSYS;
+        }
+        break;
+#endif /* CONFIG_NET_UDP */
+
+      default:
+        {
+          /* EDESTADDRREQ.  Signifies that the socket is not connection-mode
+           * and no peer address is set.
+           */
+
+          ret = -EDESTADDRREQ;
+        }
+        break;
+    }
+
+  return ret;
+}
+
+/****************************************************************************
+ * Name: local_sendto
+ *
+ * Description:
+ *   Implements the sendto() operation for the case of the local, Unix socket.
+ *
+ * Parameters:
+ *   psock    A pointer to a NuttX-specific, internal socket structure
+ *   buf      Data to send
+ *   len      Length of data to send
+ *   flags    Send flags
+ *   to       Address of recipient
+ *   tolen    The length of the address structure
+ *
+ * Returned Value:
+ *   On success, returns the number of characters sent.  On  error, -1 is
+ *   returned, and errno is set appropriately (see send_to() for the list of
+ *   appropriate errors values.
+ *
+ ****************************************************************************/
+
+ssize_t local_sendto(FAR struct socket *psock, FAR const void *buf,
+                     size_t len, int flags, FAR const struct sockaddr *to,
+                     socklen_t tolen)
+{
+  ssize_t nsent;
+
+  /* Verify that a valid address has been provided */
+
+  if (to->sa_family != AF_LOCAL || tolen < sizeof(sa_family_t))
+    {
+      nerr("ERROR: Unrecognized address family: %d\n",
+           to->sa_family);
+      return -EAFNOSUPPORT;
+    }
+
+#ifdef CONFIG_NET_UDP
+  /* If this is a connected socket, then return EISCONN */
+
+  if (psock->s_type != SOCK_DGRAM)
+    {
+      nerr("ERROR: Connected socket\n");
+      return -EISCONN;
+    }
+
+  /* Now handle the local UDP sendto() operation */
+
+  nsent = psock_local_sendto(psock, buf, len, flags, to, tolen);
+#else
+  nsent = -EISCONN;
+#endif /* CONFIG_NET_LOCAL_DGRAM */
+
+  return nsent;
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: 
+ *
+ * Description:
+ *
+ * Parameters:
+ *
+ * Returned Value:
+ *
+ * Assumptions:
+ *
+ ****************************************************************************/
+
+#endif /* CONFIG_NET_LOCAL */

net/pkt/Make.defs

@@ -39,6 +39,7 @@ ifeq ($(CONFIG_NET_PKT),y)
 
 # Socket layer
 
+SOCK_CSRCS += pkt_sockif.c
 SOCK_CSRCS += pkt_send.c
 
 # Transport layer

net/pkt/pkt.h

@@ -91,6 +91,10 @@ extern "C"
 #  define EXTERN extern
 #endif
 
+/* The packet socket interface */
+
+EXTERN const struct sock_intf_s g_pkt_sockif;
+
 /****************************************************************************
  * Public Function Prototypes
  ****************************************************************************/

net/pkt/pkt_sockif.c

@@ -0,0 +1,242 @@
+/****************************************************************************
+ * net/socket/pkt_sockif.c
+ *
+ *   Copyright (C) 2017 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>
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <assert.h>
+#include <errno.h>
+
+#include <nuttx/net/net.h>
+
+#include "pkt/pkt.h"
+
+#ifdef CONFIG_NET_PKT
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+static ssize_t pkt_setup(FAR struct socket *psock, int protocol);
+static ssize_t pkt_send(FAR struct socket *psock, FAR const void *buf,
+                 size_t len, int flags);
+static ssize_t pkt_sendto(FAR struct socket *psock, FAR const void *buf,
+                 size_t len, int flags, FAR const struct sockaddr *to,
+                 socklen_t tolen);
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+const struct sock_intf_s g_pkt_sockif =
+{
+  pkt_setup,   /* si_setup */
+  pkt_send,    /* si_send */
+  pkt_sendto,  /* si_sendto */
+};
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: pkt_sockif_alloc
+ *
+ * Description:
+ *   Allocate and attach a raw packet connection structure.
+ *
+ ****************************************************************************/
+
+static int pkt_sockif_alloc(FAR struct socket *psock)
+{
+  /* Allocate the packet socket connection structure and save in the new
+   * socket instance.
+   */
+
+  FAR struct pkt_conn_s *conn = pkt_alloc();
+  if (conn == NULL)
+    {
+      /* Failed to reserve a connection structure */
+
+      return -ENOMEM;
+    }
+
+  /* Set the reference count on the connection structure.  This reference
+   * count will be incremented only if the socket is dup'ed
+   */
+
+  DEBUGASSERT(conn->crefs == 0);
+  conn->crefs = 1;
+
+  /* Save the pre-allocated connection in the socket structure */
+
+  psock->s_conn = conn;
+  return OK;
+}
+
+/****************************************************************************
+ * Name: pkt_setup
+ *
+ * Description:
+ *   Called for socket() to verify that the provided socket type and
+ *   protocol are usable by this address family.  Perform any family-
+ *   specific socket fields.
+ *
+ * Parameters:
+ *   psock    A pointer to a user allocated socket structure to be
+ *            initialized.
+ *   protocol (see sys/socket.h)
+ *
+ * Returned Value:
+ *   Zero (OK) is returned on success.  Otherwise, a negater errno value is
+ *   returned.
+ *
+ ****************************************************************************/
+
+static int pkt_setup(FAR struct socket *psock, int protocol)
+{
+  /* Allocate the appropriate connection structure.  This reserves the
+   * the connection structure is is unallocated at this point.  It will
+   * not actually be initialized until the socket is connected.
+   *
+   * Only SOCK_RAW is supported.
+   */
+
+  if (psock->s_type == SOCK_RAW)
+    {
+      return pkt_sockif_alloc(psock);
+    }
+  else
+    {
+      return -EPROTONOSUPPORT;
+    }
+}
+
+/****************************************************************************
+ * Name: pkt_send
+ *
+ * Description:
+ *   Socket send() method for the raw packet socket.
+ *
+ * Parameters:
+ *   psock    An instance of the internal socket structure.
+ *   buf      Data to send
+ *   len      Length of data to send
+ *   flags    Send flags
+ *
+ * Returned Value:
+ *   On success, returns the number of characters sent.  On  error, -1 is
+ *   returned, and errno is set appropriately (see send() for the list of
+ *   appropriate errors values.
+ *
+ ****************************************************************************/
+
+static ssize_t pkt_send(FAR struct socket *psock, FAR const void *buf,
+                        size_t len, int flags)
+{
+  ssize_t ret;
+
+  /* Only SOCK_RAW is supported */
+
+  if (psock->s_type == SOCK_RAW)
+    {
+      /* Raw packet send */
+
+      ret = psock_pkt_send(psock, buf, len);
+    }
+  else
+    {
+      /* EDESTADDRREQ.  Signifies that the socket is not connection-mode and no peer
+       * address is set.
+       */
+
+      ret = -EDESTADDRREQ;
+    }
+
+  return ret;
+}
+
+/****************************************************************************
+ * Name: pkt_sendto
+ *
+ * Description:
+ *   Implements the sendto() operation for the case of the raw packet socket.
+ *
+ * Parameters:
+ *   psock    A pointer to a NuttX-specific, internal socket structure
+ *   buf      Data to send
+ *   len      Length of data to send
+ *   flags    Send flags
+ *   to       Address of recipient
+ *   tolen    The length of the address structure
+ *
+ * Returned Value:
+ *   On success, returns the number of characters sent.  On  error, -1 is
+ *   returned, and errno is set appropriately (see send_to() for the list of
+ *   appropriate errors values.
+ *
+ ****************************************************************************/
+
+static ssize_t pkt_sendto(FAR struct socket *psock, FAR const void *buf,
+                          size_t len, int flags, FAR const struct sockaddr *to,
+                          socklen_t tolen)
+{
+  nerr("ERROR: sendto() not supported for raw packet sockets\n");
+  return -EAFNOSUPPORT;
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: 
+ *
+ * Description:
+ *
+ * Parameters:
+ *
+ * Returned Value:
+ *
+ * Assumptions:
+ *
+ ****************************************************************************/
+
+#endif /* CONFIG_NET_PKT */

net/socket/Make.defs

@@ -1,7 +1,7 @@
 ############################################################################
 # net/socket/Make.defs
 #
-#   Copyright (C) 2014-2015 Gregory Nutt. All rights reserved.
+#   Copyright (C) 2014-2015, 2017 Gregory Nutt. All rights reserved.
 #   Author: Gregory Nutt <gnutt@nuttx.org>
 #
 # Redistribution and use in source and binary forms, with or without
@@ -39,6 +39,16 @@ SOCK_CSRCS += bind.c connect.c getsockname.c recv.c recvfrom.c send.c
 SOCK_CSRCS += sendto.c socket.c net_sockets.c net_close.c net_dupsd.c
 SOCK_CSRCS += net_dupsd2.c net_clone.c net_poll.c net_vfcntl.c
 
+# Socket address families
+
+SOCK_CSRCS += net_sockif.c
+
+ifeq ($(CONFIG_NET_IPv4),y)
+SOCK_CSRCS += inet_sockif.c
+else ifeq ($(CONFIG_NET_IPv6),y)
+SOCK_CSRCS += inet_sockif.c
+endif
+
 # TCP/IP support
 
 ifeq ($(CONFIG_NET_TCP),y)

net/socket/accept.c

@@ -224,6 +224,7 @@ int psock_accept(FAR struct socket *psock, FAR struct sockaddr *addr,
 
   newsock->s_domain = psock->s_domain;
   newsock->s_type   = SOCK_STREAM;
+  newsock->s_sockif = psock->s_sockif;
 
   /* Perform the correct accept operation for this address domain */
 

net/socket/inet_sockif.c

@@ -0,0 +1,435 @@
+/****************************************************************************
+ * net/socket/inet_sockif.c
+ *
+ *   Copyright (C) 2017 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>
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <assert.h>
+#include <errno.h>
+#include <debug.h>
+
+#include <nuttx/net/net.h>
+
+#include "tcp/tcp.h"
+#include "udp/udp.h"
+#include "socket/socket.h"
+
+#if defined(CONFIG_NET_IPv4) || defined(CONFIG_NET_IPv6)
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+static int inet_setup(FAR struct socket *psock, int protocol);
+static ssize_t inet_send(FAR struct socket *psock, FAR const void *buf,
+          size_t len, int flags);
+static ssize_t inet_sendto(FAR struct socket *psock, FAR const void *buf,
+          size_t len, int flags, FAR const struct sockaddr *to,
+          socklen_t tolen);
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+const struct sock_intf_s g_inet_sockif =
+{
+  inet_setup,   /* si_setup */
+  inet_send,    /* si_send */
+  inet_sendto,  /* si_sendto */
+};
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: inet_tcp_alloc
+ *
+ * Description:
+ *   Allocate and attach a TCP connection structure.
+ *
+ ****************************************************************************/
+
+#ifdef NET_TCP_HAVE_STACK
+static int inet_tcp_alloc(FAR struct socket *psock)
+{
+  /* Allocate the TCP connection structure */
+
+  FAR struct tcp_conn_s *conn = tcp_alloc(psock->s_domain);
+  if (conn == NULL)
+    {
+      /* Failed to reserve a connection structure */
+
+      nerr("ERROR: Failed to reserve TCP connection structure\n");
+      return -ENOMEM;
+    }
+
+  /* Set the reference count on the connection structure.  This reference
+   * count will be incremented only if the socket is dup'ed
+   */
+
+  DEBUGASSERT(conn->crefs == 0);
+  conn->crefs = 1;
+
+  /* Save the pre-allocated connection in the socket structure */
+
+  psock->s_conn = conn;
+  return OK;
+}
+#endif /* NET_TCP_HAVE_STACK */
+
+/****************************************************************************
+ * Name: inet_udp_alloc
+ *
+ * Description:
+ *   Allocate and attach a UDP connection structure.
+ *
+ ****************************************************************************/
+
+#ifdef NET_UDP_HAVE_STACK
+static int inet_udp_alloc(FAR struct socket *psock)
+{
+  /* Allocate the UDP connection structure */
+
+  FAR struct udp_conn_s *conn = udp_alloc(psock->s_domain);
+  if (conn == NULL)
+    {
+      /* Failed to reserve a connection structure */
+
+      nerr("ERROR: Failed to reserve UDP connection structure\n");
+      return -ENOMEM;
+    }
+
+  /* Set the reference count on the connection structure.  This reference
+   * count will be incremented only if the socket is dup'ed
+   */
+
+  DEBUGASSERT(conn->crefs == 0);
+  conn->crefs = 1;
+
+  /* Save the pre-allocated connection in the socket structure */
+
+  psock->s_conn = conn;
+  return OK;
+}
+#endif /* NET_UDP_HAVE_STACK */
+
+/****************************************************************************
+ * Name: inet_setup
+ *
+ * Description:
+ *   Called for socket() to verify that the provided socket type and
+ *   protocol are usable by this address family.  Perform any family-
+ *   specific socket fields.
+ *
+ *   NOTE:  This is common logic for both the AF_INET and AF_INET6 address
+ *   families.
+ *
+ * Parameters:
+ *   psock    A pointer to a user allocated socket structure to be initialized.
+ *   protocol (see sys/socket.h)
+ *
+ * Returned Value:
+ *   Zero (OK) is returned on success.  Otherwise, a negater errno value is
+ *   returned.
+ *
+ ****************************************************************************/
+
+static int inet_setup(FAR struct socket *psock, int protocol)
+{
+  /* Allocate the appropriate connection structure.  This reserves the
+   * the connection structure is is unallocated at this point.  It will
+   * not actually be initialized until the socket is connected.
+   *
+   * Only SOCK_STREAM and SOCK_DGRAM and possible SOCK_RAW are supported.
+   */
+
+  switch (psock->s_type)
+    {
+#ifdef CONFIG_NET_TCP
+      case SOCK_STREAM:
+        if (protocol != 0 && protocol != IPPROTO_TCP)
+          {
+            nerr("ERROR: Unsupported stream protocol: %d\n", protocol);
+            return -EPROTONOSUPPORT;
+          }
+
+#ifdef NET_TCP_HAVE_STACK
+        /* Allocate and attach the TCP connection structure */
+
+        return inet_tcp_alloc(psock);
+#else
+        return = -ENETDOWN;
+#endif
+#endif /* CONFIG_NET_TCP */
+
+#ifdef CONFIG_NET_UDP
+      case SOCK_DGRAM:
+        if (protocol != 0 && protocol != IPPROTO_UDP)
+          {
+            nerr("ERROR: Unsupported datagram protocol: %d\n", protocol);
+            return -EPROTONOSUPPORT;
+          }
+
+#ifdef NET_UDP_HAVE_STACK
+        /* Allocate and attach the UDP connection structure */
+
+        return inet_udp_alloc(psock);
+#else
+        return -ENETDOWN;
+#endif
+#endif /* CONFIG_NET_UDP */
+
+      default:
+        nerr("ERROR: Unsupported type: %d\n", psock->s_type);
+        return -EPROTONOSUPPORT;
+    }
+}
+
+/****************************************************************************
+ * Name: inet_send
+ *
+ * Description:
+ *   The inet_send() call may be used only when the socket is in a connected
+ *   state  (so that the intended recipient is known).
+ *
+ * Parameters:
+ *   psock    An instance of the internal socket structure.
+ *   buf      Data to send
+ *   len      Length of data to send
+ *   flags    Send flags
+ *
+ * Returned Value:
+ *   On success, returns the number of characters sent.  On  error, -1 is
+ *   returned, and errno is set appropriately (see send() for the list of
+ *   appropriate errors values.
+ *
+ ****************************************************************************/
+
+static ssize_t inet_send(FAR struct socket *psock, FAR const void *buf,
+                         size_t len, int flags)
+{
+  ssize_t ret;
+
+  switch (psock->s_type)
+    {
+#ifdef CONFIG_NET_TCP
+      case SOCK_STREAM:
+        {
+#ifdef CONFIG_NET_6LOWPAN
+          /* Try 6LoWPAN TCP packet send */
+
+          ret = psock_6lowpan_tcp_send(psock, buf, len);
+
+#if defined(CONFIG_NETDEV_MULTINIC) && defined(NET_TCP_HAVE_STACK)
+          if (ret < 0)
+            {
+              /* TCP/IP packet send */
+
+              ret = psock_tcp_send(psock, buf, len);
+            }
+#endif /* CONFIG_NETDEV_MULTINIC && NET_TCP_HAVE_STACK */
+#elif defined(NET_TCP_HAVE_STACK)
+          ret = psock_tcp_send(psock, buf, len);
+#else
+          ret = -ENOSYS;
+#endif /* CONFIG_NET_6LOWPAN */
+        }
+        break;
+#endif /* CONFIG_NET_TCP */
+
+#ifdef CONFIG_NET_UDP
+      case SOCK_DGRAM:
+        {
+#if defined(CONFIG_NET_6LOWPAN)
+           /* Try 6LoWPAN UDP packet send */
+
+           ret = psock_6lowpan_udp_send(psock, buf, len);
+
+#if defined(CONFIG_NETDEV_MULTINIC) && defined(NET_UDP_HAVE_STACK)
+          if (ret < 0)
+            {
+              /* UDP/IP packet send */
+
+              ret = psock_udp_send(psock, buf, len);
+            }
+#endif /* CONFIG_NETDEV_MULTINIC && NET_UDP_HAVE_STACK */
+#elif defined(NET_UDP_HAVE_STACK)
+          /* Only UDP/IP packet send */
+
+          ret = psock_udp_send(psock, buf, len);
+#else
+          ret = -ENOSYS;
+#endif /* CONFIG_NET_6LOWPAN */
+        }
+        break;
+#endif /* CONFIG_NET_UDP */
+
+      default:
+        {
+          /* EDESTADDRREQ.  Signifies that the socket is not connection-mode
+           * and no peer address is set.
+           */
+
+          nerr("ERROR:  Bad socket type: %d\n", psock->s_type);
+          ret = -EDESTADDRREQ;
+        }
+        break;
+    }
+
+  return ret;
+}
+
+/****************************************************************************
+ * Name: inet_sendto
+ *
+ * Description:
+ *   Implements the sendto() operation for the case of the AF_INET and
+ *   AF_INET6 sockets.
+ *
+ * Parameters:
+ *   psock    A pointer to a NuttX-specific, internal socket structure
+ *   buf      Data to send
+ *   len      Length of data to send
+ *   flags    Send flags
+ *   to       Address of recipient
+ *   tolen    The length of the address structure
+ *
+ * Returned Value:
+ *   On success, returns the number of characters sent.  On  error, -1 is
+ *   returned, and errno is set appropriately (see send_to() for the list of
+ *   appropriate errors values.
+ *
+ ****************************************************************************/
+
+static ssize_t inet_sendto(FAR struct socket *psock, FAR const void *buf,
+                           size_t len, int flags, FAR const struct sockaddr *to,
+                           socklen_t tolen)
+{
+  socklen_t minlen;
+  ssize_t nsent;
+
+  /* Verify that a valid address has been provided */
+
+  switch (to->sa_family)
+    {
+#ifdef CONFIG_NET_IPv4
+    case AF_INET:
+      minlen = sizeof(struct sockaddr_in);
+      break;
+#endif
+
+#ifdef CONFIG_NET_IPv6
+    case AF_INET6:
+      minlen = sizeof(struct sockaddr_in6);
+      break;
+#endif
+
+#ifdef CONFIG_NET_LOCAL_DGRAM
+    case AF_LOCAL:
+      minlen = sizeof(sa_family_t);
+      break;
+#endif
+
+    default:
+      nerr("ERROR: Unrecognized address family: %d\n", to->sa_family);
+      return -EAFNOSUPPORT;
+    }
+
+  if (tolen < minlen)
+    {
+      nerr("ERROR: Invalid address length: %d < %d\n", tolen, minlen);
+      return -EBADF;
+    }
+
+#ifdef CONFIG_NET_UDP
+  /* If this is a connected socket, then return EISCONN */
+
+  if (psock->s_type != SOCK_DGRAM)
+    {
+      nerr("ERROR: Connected socket\n");
+      return -EBADF;
+    }
+
+  /* Now handle the INET sendto() operation */
+
+#if defined(CONFIG_NET_6LOWPAN)
+  /* Try 6LoWPAN UDP packet sendto() */
+
+  nsent = psock_6lowpan_udp_sendto(psock, buf, len, flags, to, tolen);
+
+#if defined(CONFIG_NETDEV_MULTINIC) && defined(NET_UDP_HAVE_STACK)
+  if (nsent < 0)
+    {
+      /* UDP/IP packet sendto */
+
+      nsent = psock_udp_sendto(psock, buf, len, flags, to, tolen);
+    }
+#endif /* CONFIG_NETDEV_MULTINIC && NET_UDP_HAVE_STACK */
+#elif defined(NET_UDP_HAVE_STACK)
+  nsent = psock_udp_sendto(psock, buf, len, flags, to, tolen);
+#else
+  nsent = -ENOSYS;
+#endif /* CONFIG_NET_6LOWPAN */
+#else
+  nsent = -EISCONN;
+#endif /* CONFIG_NET_UDP */
+
+  return nsent;
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: 
+ *
+ * Description:
+ *
+ * Parameters:
+ *
+ * Returned Value:
+ *
+ * Assumptions:
+ *
+ ****************************************************************************/
+
+#endif /* CONFIG_NET_IPv4 || CONFIG_NET_IPv6 */

net/socket/net_clone.c

@@ -79,6 +79,7 @@ int net_clone(FAR struct socket *psock1, FAR struct socket *psock2)
 
   psock2->s_domain   = psock1->s_domain;    /* IP domain: PF_INET, PF_INET6, or PF_PACKET */
   psock2->s_type     = psock1->s_type;      /* Protocol type: Only SOCK_STREAM or SOCK_DGRAM */
+  psock2->s_sockif   = psock1->s_sockif;    /* Socket interface */
   psock2->s_flags    = psock1->s_flags;     /* See _SF_* definitions */
 #ifdef CONFIG_NET_SOCKOPTS
   psock2->s_options  = psock1->s_options;   /* Selected socket options */

net/socket/net_sockif.c

@@ -0,0 +1,111 @@
+/****************************************************************************
+ * net/socket/net_sockif.c
+ *
+ *   Copyright (C) 2017 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>
+
+#include <sys/types.h>
+#include <errno.h>
+#include <debug.h>
+
+#include <nuttx/net/net.h>
+
+#include "local/local.h"
+#include "pkt/pkt.h"
+#include "socket/socket.h"
+
+#ifdef CONFIG_NET
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: net_sockif
+ *
+ * Description:
+ *   Return the socket interface associated with this address family.
+ *
+ * Parameters:
+ *   family - Address family
+ *
+ * Returned Value:
+ *   On success, a non-NULL instance of struct sock_intf_s is returned.  NULL
+ *   is returned only if the address family is not supported.
+ *
+ ****************************************************************************/
+
+FAR const struct sock_intf_s *net_sockif(sa_family_t family)
+{
+  FAR const struct sock_intf_s *sockif = NULL;
+
+  /* Get the socket interface */
+
+  switch (family)
+    {
+#if defined(CONFIG_NET_IPv4) || defined(CONFIG_NET_IPv6)
+#ifdef CONFIG_NET_IPv4
+    case PF_INET:
+#endif
+#ifdef CONFIG_NET_IPv6
+    case PF_INET6:
+#endif
+      sockif = &g_inet_sockif;
+      break;
+#endif
+
+#ifdef CONFIG_NET_LOCAL
+    case PF_LOCAL:
+      sockif = &g_local_sockif;
+      break;
+#endif
+
+#ifdef CONFIG_NET_PKT
+    case PF_PACKET:
+      sockif = &g_pkt_sockif;
+      break;
+#endif
+
+    default:
+      nerr("ERROR: Address family unsupported: %d\n", family);
+    }
+
+  return sockif;
+}
+
+#endif /* CONFIG_NET */

net/socket/send.c

@@ -42,6 +42,8 @@
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <errno.h>
+#include <assert.h>
+#include <debug.h>
 
 #include <nuttx/cancelpt.h>
 
@@ -126,132 +128,32 @@ ssize_t psock_send(FAR struct socket *psock, FAR const void *buf, size_t len,
 {
   ssize_t ret;
 
+  DEBUGASSERT(psock != NULL && buf != NULL);
+
   /* Treat as a cancellation point */
 
   (void)enter_cancellation_point();
 
-  switch (psock->s_type)
-    {
-#if defined(CONFIG_NET_PKT)
-      case SOCK_RAW:
-        {
-          /* Raw packet send */
-
-          ret = psock_pkt_send(psock, buf, len);
-        }
-        break;
-#endif
-
-#if defined(CONFIG_NET_TCP) || defined(CONFIG_NET_LOCAL_STREAM)
-      case SOCK_STREAM:
-        {
-#ifdef CONFIG_NET_LOCAL_STREAM
-#ifdef CONFIG_NET_TCP
-          if (psock->s_domain == PF_LOCAL)
-#endif
-            {
-              /* Local TCP packet send */
-
-              ret = psock_local_send(psock, buf, len, flags);
-            }
-#endif /* CONFIG_NET_LOCAL_STREAM */
-
-#ifdef CONFIG_NET_TCP
-#ifdef CONFIG_NET_LOCAL_STREAM
-          else
-#endif
-            {
-#ifdef CONFIG_NET_6LOWPAN
-              /* Try 6LoWPAN TCP packet send */
-
-              ret = psock_6lowpan_tcp_send(psock, buf, len);
-
-#if defined(CONFIG_NETDEV_MULTINIC) && defined(NET_TCP_HAVE_STACK)
-              if (ret < 0)
-                {
-                  /* TCP/IP packet send */
-
-                  ret = psock_tcp_send(psock, buf, len);
-                }
-#endif /* CONFIG_NETDEV_MULTINIC && NET_TCP_HAVE_STACK */
-#elif defined(NET_TCP_HAVE_STACK)
-              ret = psock_tcp_send(psock, buf, len);
-#else
-              ret = -ENOSYS;
-#endif /* CONFIG_NET_6LOWPAN */
-            }
-#endif /* CONFIG_NET_TCP */
-        }
-        break;
-#endif /* CONFIG_NET_TCP || CONFIG_NET_LOCAL_STREAM */
-
-#ifdef CONFIG_NET_UDP
-      case SOCK_DGRAM:
-        {
-#ifdef CONFIG_NET_LOCAL_DGRAM
-#ifdef CONFIG_NET_UDP
-          if (psock->s_domain == PF_LOCAL)
-#endif
-            {
-              /* Local UDP packet send */
-#warning Missing logic
-              ret = -ENOSYS;
-            }
-#endif /* CONFIG_NET_LOCAL_DGRAM */
-
-#ifdef CONFIG_NET_UDP
-#ifdef CONFIG_NET_LOCAL_DGRAM
-          else
-#endif
-            {
-#if defined(CONFIG_NET_6LOWPAN)
-              /* Try 6LoWPAN UDP packet send */
-
-              ret = psock_6lowpan_udp_send(psock, buf, len);
-
-#if defined(CONFIG_NETDEV_MULTINIC) && defined(NET_UDP_HAVE_STACK)
-              if (ret < 0)
-                {
-                  /* UDP/IP packet send */
-
-                  ret = psock_udp_send(psock, buf, len);
-                }
-#endif /* CONFIG_NETDEV_MULTINIC && NET_UDP_HAVE_STACK */
-#elif defined(NET_UDP_HAVE_STACK)
-              /* Only UDP/IP packet send */
-
-              ret = psock_udp_send(psock, buf, len);
-#else
-              ret = -ENOSYS;
-#endif /* CONFIG_NET_6LOWPAN */
-            }
-#endif /* CONFIG_NET_UDP */
-        }
-        break;
-#endif /* CONFIG_NET_UDP */
+  /* Special case user sockets */
 
 #ifdef CONFIG_NET_USRSOCK
-      case SOCK_USRSOCK_TYPE:
-        {
-          ret = usrsock_sendto(psock, buf, len, NULL, 0);
-        }
-        break;
+  if (psock->s_type SOCK_USRSOCK_TYPE)
+    {
+      ret = usrsock_sendto(psock, buf, len, NULL, 0);
+    }
+  else
 #endif /*CONFIG_NET_USRSOCK*/
+    {
+      /* Let the address family's send() method handle the operation */
 
-      default:
-        {
-          /* EDESTADDRREQ.  Signifies that the socket is not connection-mode
-           * and no peer address is set.
-           */
-
-          ret = -EDESTADDRREQ;
-        }
-        break;
+      DEBUGASSERT(psock->s_sockif != NULL && psock->s_sockif->si_send != NULL);
+      ret = psock->s_sockif->si_send(psock, buf, len, flags);
     }
 
   leave_cancellation_point();
   if (ret < 0)
     {
+      nerr("ERROR: socket si_send() (or usrsock_sendto()) failed: %d\n", ret);
       set_errno(-ret);
       ret = ERROR;
     }

net/socket/sendto.c

@@ -42,6 +42,7 @@
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <stdint.h>
+#include <assert.h>
 #include <errno.h>
 #include <debug.h>
 
@@ -127,18 +128,16 @@ ssize_t psock_sendto(FAR struct socket *psock, FAR const void *buf,
                      size_t len, int flags, FAR const struct sockaddr *to,
                      socklen_t tolen)
 {
-  socklen_t minlen;
-#if defined(CONFIG_NET_UDP) || defined(CONFIG_NET_LOCAL_DGRAM) || \
-    defined(CONFIG_NET_USRSOCK)
   ssize_t nsent;
-#endif
   int errcode;
 
+  DEBUGASSERT(psock != NULL && buf != NULL);
+
   /* If to is NULL or tolen is zero, then this function is same as send (for
    * connected socket types)
    */
 
-  if (!to || !tolen)
+  if (to == NULL || tolen <= 0)
     {
 #if defined(CONFIG_NET_TCP) || defined(CONFIG_NET_LOCAL_STREAM) || \
     defined(CONFIG_NET_USRSOCK)
@@ -156,122 +155,35 @@ ssize_t psock_sendto(FAR struct socket *psock, FAR const void *buf,
       /* Perform the usrsock sendto operation */
 
       nsent = usrsock_sendto(psock, buf, len, to, tolen);
-      if (nsent < 0)
-        {
-          errcode = -nsent;
-          goto errout;
-        }
-
-      return nsent;
     }
-#endif
-
-  /* Verify that a valid address has been provided */
-
-  switch (to->sa_family)
-    {
-#ifdef CONFIG_NET_IPv4
-    case AF_INET:
-      minlen = sizeof(struct sockaddr_in);
-      break;
-#endif
-
-#ifdef CONFIG_NET_IPv6
-    case AF_INET6:
-      minlen = sizeof(struct sockaddr_in6);
-      break;
-#endif
-
-#ifdef CONFIG_NET_LOCAL_DGRAM
-    case AF_LOCAL:
-      minlen = sizeof(sa_family_t);
-      break;
-#endif
-
-    default:
-      nerr("ERROR: Unrecognized address family: %d\n", to->sa_family);
-      errcode = EAFNOSUPPORT;
-      goto errout;
-    }
-
-  if (tolen < minlen)
-    {
-      nerr("ERROR: Invalid address length: %d < %d\n", tolen, minlen);
-      errcode = EBADF;
-      goto errout;
-    }
-
-  /* Verify that the psock corresponds to valid, allocated socket */
-
-  if (!psock || psock->s_crefs <= 0)
-    {
-      nerr("ERROR: Invalid socket\n");
-      errcode = EBADF;
-      goto errout;
-    }
-
-  /* If this is a connected socket, then return EISCONN */
-
-  if (psock->s_type != SOCK_DGRAM)
-    {
-      nerr("ERROR: Connected socket\n");
-      errcode = EISCONN;
-      goto errout;
-    }
-
-#if defined(CONFIG_NET_UDP) || defined(CONFIG_NET_LOCAL_DGRAM)
-  /* Now handle the sendto() operation according to the socket domain,
-   * currently either IP or Unix domains.
-   */
-
-#ifdef CONFIG_NET_LOCAL_DGRAM
-#ifdef CONFIG_NET_UDP
-  if (psock->s_domain == PF_LOCAL)
-#endif
-    {
-      nsent = psock_local_sendto(psock, buf, len, flags, to, tolen);
-    }
-#endif /* CONFIG_NET_LOCAL_DGRAM */
-
-#ifdef CONFIG_NET_UDP
-#ifdef CONFIG_NET_LOCAL_DGRAM
   else
 #endif
     {
-#if defined(CONFIG_NET_6LOWPAN)
-      /* Try 6LoWPAN UDP packet sendto() */
+      /* Verify that the psock corresponds to valid, allocated socket */
 
-      nsent = psock_6lowpan_udp_sendto(psock, buf, len, flags, to, tolen);
-
-#if defined(CONFIG_NETDEV_MULTINIC) && defined(NET_UDP_HAVE_STACK)
-      if (nsent < 0)
+      if (!psock || psock->s_crefs <= 0)
         {
-          /* UDP/IP packet sendto */
-
-          nsent = psock_udp_sendto(psock, buf, len, flags, to, tolen);
+          nerr("ERROR: Invalid socket\n");
+          errcode = EBADF;
+          goto errout;
         }
-#endif /* CONFIG_NETDEV_MULTINIC && NET_UDP_HAVE_STACK */
-#elif defined(NET_UDP_HAVE_STACK)
-      nsent = psock_udp_sendto(psock, buf, len, flags, to, tolen);
-#else
-      nsent = -ENOSYS;
-#endif /* CONFIG_NET_6LOWPAN */
+
+      /* Let the address family's send() method handle the operation */
+
+      DEBUGASSERT(psock->s_sockif != NULL && psock->s_sockif->si_send != NULL);
+      nsent = psock->s_sockif->si_send(psock, buf, len, flags);
     }
-#endif /* CONFIG_NET_UDP */
 
   /* Check if the domain-specific sendto() logic failed */
 
   if (nsent < 0)
     {
-      nerr("ERROR: UDP or Unix domain sendto() failed: %ld\n", (long)nsent);
+      nerr("ERROR:  Family-specific send failed: %ld\n", (long)nsent);
       errcode = -nsent;
       goto errout;
     }
 
   return nsent;
-#else
-  errcode = ENOSYS;
-#endif /* CONFIG_NET_UDP || CONFIG_NET_LOCAL_DGRAM */
 
 errout:
   set_errno(errcode);

net/socket/socket.c

@@ -38,168 +38,21 @@
  ****************************************************************************/
 
 #include <nuttx/config.h>
-#ifdef CONFIG_NET
 
 #include <sys/socket.h>
 #include <errno.h>
 #include <assert.h>
 #include <debug.h>
 
-#include <nuttx/net/udp.h>
-
-#include "socket/socket.h"
-#include "tcp/tcp.h"
-#include "udp/udp.h"
-#include "pkt/pkt.h"
-#include "local/local.h"
 #include "usrsock/usrsock.h"
+#include "socket/socket.h"
+
+#ifdef CONFIG_NET
 
 /****************************************************************************
  * Private Functions
  ****************************************************************************/
 
-/****************************************************************************
- * Name: psock_tcp_alloc
- *
- * Description:
- *   Allocate and attach a TCP connection structure.
- *
- ****************************************************************************/
-
-#ifdef NET_TCP_HAVE_STACK
-static int psock_tcp_alloc(FAR struct socket *psock)
-{
-  /* Allocate the TCP connection structure */
-
-  FAR struct tcp_conn_s *conn = tcp_alloc(psock->s_domain);
-  if (!conn)
-    {
-      /* Failed to reserve a connection structure */
-
-      return -ENOMEM;
-    }
-
-  /* Set the reference count on the connection structure.  This reference
-   * count will be incremented only if the socket is dup'ed
-   */
-
-  DEBUGASSERT(conn->crefs == 0);
-  conn->crefs = 1;
-
-  /* Save the pre-allocated connection in the socket structure */
-
-  psock->s_conn = conn;
-  return OK;
-}
-#endif /* NET_TCP_HAVE_STACK */
-
-/****************************************************************************
- * Name: psock_udp_alloc
- *
- * Description:
- *   Allocate and attach a UDP connection structure.
- *
- ****************************************************************************/
-
-#ifdef NET_UDP_HAVE_STACK
-static int psock_udp_alloc(FAR struct socket *psock)
-{
-  /* Allocate the UDP connection structure */
-
-  FAR struct udp_conn_s *conn = udp_alloc(psock->s_domain);
-  if (!conn)
-    {
-      /* Failed to reserve a connection structure */
-
-      return -ENOMEM;
-    }
-
-  /* Set the reference count on the connection structure.  This reference
-   * count will be incremented only if the socket is dup'ed
-   */
-
-  DEBUGASSERT(conn->crefs == 0);
-  conn->crefs = 1;
-
-  /* Save the pre-allocated connection in the socket structure */
-
-  psock->s_conn = conn;
-  return OK;
-}
-#endif /* NET_UDP_HAVE_STACK */
-
-/****************************************************************************
- * Name: psock_pkt_alloc
- *
- * Description:
- *   Allocate and attach a raw packet connection structure.
- *
- ****************************************************************************/
-
-#ifdef CONFIG_NET_PKT
-static int psock_pkt_alloc(FAR struct socket *psock)
-{
-  /* Allocate the packet socket connection structure and save in the new
-   * socket instance.
-   */
-
-  FAR struct pkt_conn_s *conn = pkt_alloc();
-  if (!conn)
-    {
-      /* Failed to reserve a connection structure */
-
-      return -ENOMEM;
-    }
-
-  /* Set the reference count on the connection structure.  This reference
-   * count will be incremented only if the socket is dup'ed
-   */
-
-  DEBUGASSERT(conn->crefs == 0);
-  conn->crefs = 1;
-
-  /* Save the pre-allocated connection in the socket structure */
-
-  psock->s_conn = conn;
-  return OK;
-}
-#endif /* CONFIG_NET_PKT */
-
-/****************************************************************************
- * Name: psock_local_alloc
- *
- * Description:
- *   Allocate and attach a local, Unix domain connection structure.
- *
- ****************************************************************************/
-
-#ifdef CONFIG_NET_LOCAL
-static int psock_local_alloc(FAR struct socket *psock)
-{
-  /* Allocate the local connection structure */
-
-  FAR struct local_conn_s *conn = local_alloc();
-  if (!conn)
-    {
-      /* Failed to reserve a connection structure */
-
-      return -ENOMEM;
-    }
-
-  /* Set the reference count on the connection structure.  This reference
-   * count will be incremented only if the socket is dup'ed
-   */
-
-  DEBUGASSERT(conn->lc_crefs == 0);
-  conn->lc_crefs = 1;
-
-  /* Save the pre-allocated connection in the socket structure */
-
-  psock->s_conn = conn;
-  return OK;
-}
-#endif /* CONFIG_NET_LOCAL */
-
 /****************************************************************************
  * Name: usrsock_socket_setup
  *
@@ -316,148 +169,21 @@ static int usrsock_socket_setup(int domain, int type, int protocol,
 
 int psock_socket(int domain, int type, int protocol, FAR struct socket *psock)
 {
-#ifdef CONFIG_NET_LOCAL
-  bool ipdomain = false;
-#endif
-  bool dgramok  = false;
-  int ret;
+  FAR const struct sock_intf_s *sockif = NULL;
   int errcode;
-
+  int ret;
+ 
 #ifdef CONFIG_NET_USRSOCK
   ret = usrsock_socket_setup(domain, type, protocol, psock);
   if (ret < 0)
     {
+      nerr("ERROR: usrsock_socket_setup() failed: %d\n", ret);
       errcode = -ret;
       goto errout;
     }
 #endif /* CONFIG_NET_USRSOCK */
 
-  /* Only PF_INET, PF_INET6 or PF_PACKET domains supported */
-
-  switch (domain)
-    {
-#ifdef CONFIG_NET_IPv4
-    case PF_INET:
-#ifdef CONFIG_NET_LOCAL
-      ipdomain = true;
-#endif
-      dgramok  = true;
-      break;
-#endif
-
-#ifdef CONFIG_NET_IPv6
-    case PF_INET6:
-#ifdef CONFIG_NET_LOCAL
-      ipdomain = true;
-#endif
-      dgramok  = true;
-      break;
-#endif
-
-#ifdef CONFIG_NET_LOCAL
-    case PF_LOCAL:
-      dgramok = true;
-      break;
-#endif
-
-#ifdef CONFIG_NET_PKT
-    case PF_PACKET:
-      break;
-#endif
-
-    default:
-      errcode = EAFNOSUPPORT;
-      goto errout;
-    }
-
-#if defined(CONFIG_NET_LOCAL) && !defined(CONFIG_NET_LOCAL_STREAM) && !defined(CONFIG_NET_LOCAL_DGRAM)
-  UNUSED(ipdomain);
-#endif
-
-  /* Only SOCK_STREAM, SOCK_DGRAM and possible SOCK_RAW are supported */
-
-  switch (type)
-    {
-#if defined(CONFIG_NET_TCP) || defined(CONFIG_NET_LOCAL_STREAM)
-      case SOCK_STREAM:
-#ifdef CONFIG_NET_TCP
-#ifdef CONFIG_NET_LOCAL_STREAM
-        if (ipdomain)
-#endif
-          {
-            if ((protocol != 0 && protocol != IPPROTO_TCP) || !dgramok)
-              {
-                errcode = EPROTONOSUPPORT;
-                goto errout;
-              }
-          }
-#endif /* CONFIG_NET_TCP */
-
-#ifdef CONFIG_NET_LOCAL_STREAM
-#ifdef CONFIG_NET_TCP
-        else
-#endif
-          {
-            if (protocol != 0 || !dgramok)
-              {
-                errcode = EPROTONOSUPPORT;
-                goto errout;
-              }
-          }
-#endif /* CONFIG_NET_LOCAL_STREAM */
-
-        break;
-#endif /* CONFIG_NET_TCP || CONFIG_NET_LOCAL_STREAM */
-
-#if defined(CONFIG_NET_UDP) || defined(CONFIG_NET_LOCAL_DGRAM)
-      case SOCK_DGRAM:
-#ifdef CONFIG_NET_UDP
-#ifdef CONFIG_NET_LOCAL_DGRAM
-        if (ipdomain)
-#endif
-          {
-            if ((protocol != 0 && protocol != IPPROTO_UDP) || !dgramok)
-              {
-                errcode = EPROTONOSUPPORT;
-                goto errout;
-              }
-          }
-#endif /* CONFIG_NET_UDP */
-
-#ifdef CONFIG_NET_LOCAL_DGRAM
-#ifdef CONFIG_NET_UDP
-        else
-#endif
-          {
-            if (protocol != 0 || !dgramok)
-              {
-                errcode = EPROTONOSUPPORT;
-                goto errout;
-              }
-          }
-#endif /* CONFIG_NET_LOCAL_DGRAM */
-
-        break;
-#endif /* CONFIG_NET_UDP || CONFIG_NET_LOCAL_DGRAM */
-
-#ifdef CONFIG_NET_PKT
-      case SOCK_RAW:
-        if (dgramok)
-          {
-            errcode = EPROTONOSUPPORT;
-            goto errout;
-          }
-
-        break;
-#endif
-
-      default:
-        errcode = EPROTONOSUPPORT;
-        goto errout;
-    }
-
-  /* Everything looks good.  Initialize the socket structure */
-  /* Save the protocol type */
+  /* Initialize the socket structure */
 
   psock->s_domain = domain;
   psock->s_type   = type;
@@ -466,115 +192,29 @@ int psock_socket(int domain, int type, int protocol, FAR struct socket *psock)
   psock->s_sndcb  = NULL;
 #endif
 
-  /* Allocate the appropriate connection structure.  This reserves the
-   * the connection structure is is unallocated at this point.  It will
-   * not actually be initialized until the socket is connected.
+  /* Get the socket interface */
+
+  sockif = net_sockif(domain);
+  if (sockif == NULL)
+    {
+      nerr("ERROR: socket address family unsupported: %d\n", domain);
+      errcode = EAFNOSUPPORT;
+      goto errout;
+    }
+
+  /* The remaining of the socket initialization depends on the address
+   * family.
    */
 
-  errcode = ENOMEM; /* Assume failure to allocate connection instance */
-  switch (type)
+  DEBUGASSERT(sockif->si_setup != NULL);
+  psock->s_sockif = sockif;
+
+  ret = sockif->si_setup(psock, protocol);
+  if (ret < 0)
     {
-#if defined(CONFIG_NET_TCP) || defined(CONFIG_NET_LOCAL_STREAM)
-      case SOCK_STREAM:
-        {
-#ifdef CONFIG_NET_TCP
-#ifdef CONFIG_NET_LOCAL_STREAM
-          if (ipdomain)
-#endif
-            {
-#ifdef NET_TCP_HAVE_STACK
-              /* Allocate and attach the TCP connection structure */
-
-              ret = psock_tcp_alloc(psock);
-#else
-              ret = -ENETDOWN;
-#endif
-            }
-#endif /* CONFIG_NET_TCP */
-
-#ifdef CONFIG_NET_LOCAL_STREAM
-#ifdef CONFIG_NET_TCP
-         else
-#endif
-            {
-              /* Allocate and attach the local connection structure */
-
-              ret = psock_local_alloc(psock);
-            }
-#endif /* CONFIG_NET_LOCAL_STREAM */
-
-          /* Check for failures to allocate the connection structure. */
-
-          if (ret < 0)
-            {
-              /* Failed to reserve a connection structure */
-
-              errcode = -ret;
-              goto errout;
-            }
-        }
-        break;
-#endif
-
-#if defined(CONFIG_NET_UDP) || defined(CONFIG_NET_LOCAL_DGRAM)
-      case SOCK_DGRAM:
-        {
-#ifdef CONFIG_NET_UDP
-#ifdef CONFIG_NET_LOCAL_DGRAM
-          if (ipdomain)
-#endif
-            {
-#ifdef NET_UDP_HAVE_STACK
-              /* Allocate and attach the UDP connection structure */
-
-              ret = psock_udp_alloc(psock);
-#else
-              ret = -ENETDOWN;
-#endif
-            }
-#endif /* CONFIG_NET_UDP */
-
-#ifdef CONFIG_NET_LOCAL_DGRAM
-#ifdef CONFIG_NET_UDP
-         else
-#endif
-            {
-              /* Allocate and attach the local connection structure */
-
-              ret = psock_local_alloc(psock);
-            }
-#endif /* CONFIG_NET_LOCAL_DGRAM */
-
-          /* Check for failures to allocate the connection structure. */
-
-          if (ret < 0)
-            {
-              /* Failed to reserve a connection structure */
-
-              errcode = -ret;
-              goto errout;
-            }
-        }
-        break;
-#endif
-
-#ifdef CONFIG_NET_PKT
-      case SOCK_RAW:
-        {
-          ret = psock_pkt_alloc(psock);
-          if (ret < 0)
-            {
-              /* Failed to reserve a connection structure */
-
-              errcode = -ret;
-              goto errout;
-            }
-        }
-        break;
-#endif
-
-      default:
-        break;
+      nerr("ERROR: socket si_setup() failed: %d\n", ret);
+      errcode = -ret;
+      goto errout;
     }
 
   return OK;
@@ -632,6 +272,7 @@ int socket(int domain, int type, int protocol)
   sockfd = sockfd_allocate(0);
   if (sockfd < 0)
     {
+      nerr("ERROR: Failed to allodate a socket descriptor\n");
       set_errno(ENFILE);
       return ERROR;
     }
@@ -650,8 +291,9 @@ int socket(int domain, int type, int protocol)
   ret = psock_socket(domain, type, protocol, psock);
   if (ret < 0)
     {
-      /* Error already set by psock_socket() */
+      /* errno already set by psock_socket() */
 
+      nerr("ERROR: psock_socket() failed: %d\n", ret);
       goto errout;
     }
 

net/socket/socket.h

@@ -149,6 +149,10 @@ extern "C"
 #define EXTERN extern
 #endif
 
+#if defined(CONFIG_NET_IPv4) || defined(CONFIG_NET_IPv6)
+EXTERN const struct sock_intf_s g_inet_sockif;
+#endif
+
 /****************************************************************************
  * Public Function Prototypes
  ****************************************************************************/
@@ -223,6 +227,23 @@ void sockfd_release(int sockfd);
 
 FAR struct socket *sockfd_socket(int sockfd);
 
+/****************************************************************************
+ * Name: net_sockif
+ *
+ * Description:
+ *   Return the socket interface associated with this address family.
+ *
+ * Parameters:
+ *   family - Address family
+ *
+ * Returned Value:
+ *   On success, a non-NULL instance of struct sock_intf_s is returned.  NULL
+ *   is returned only if the address family is not supported.
+ *
+ ****************************************************************************/
+
+FAR const struct sock_intf_s *net_sockif(sa_family_t family);
+
 /****************************************************************************
  * Name: net_startmonitor
  *