TCP networking: Add support for network driver events

net/devif/devif.h

@@ -193,8 +193,11 @@
 
 /* The set of events that and implications to the TCP connection state */
 
-#define TCP_CONN_EVENTS (TCP_CLOSE | TCP_ABORT | TCP_CONNECTED | \
+#define TCP_CONN_EVENTS \
-                         TCP_TIMEDOUT | NETDEV_DOWN)
+  (TCP_CLOSE | TCP_ABORT | TCP_CONNECTED | TCP_TIMEDOUT | NETDEV_DOWN)
+
+#define TCP_DISCONN_EVENTS \
+  (TCP_CLOSE | TCP_ABORT | TCP_TIMEDOUT | NETDEV_DOWN)
 
 /* IPv4/IPv6 Helpers */
 

net/netdev/netdev.h

@@ -68,9 +68,11 @@ extern "C"
 #define EXTERN extern
 #endif
 
-/* List of registered Ethernet device drivers */
-
 #if CONFIG_NSOCKET_DESCRIPTORS > 0
+/* List of registered Ethernet device drivers.  This duplicates a declaration
+ * in net/netdev/netdev.h
+ */
+
 EXTERN struct net_driver_s *g_netdevices;
 #endif
 

net/socket/connect.c

@@ -118,7 +118,7 @@ static inline int psock_setup_callbacks(FAR struct socket *psock,
       /* Set up the connection "interrupt" handler */
 
       pstate->tc_cb->flags   = (TCP_NEWDATA | TCP_CLOSE | TCP_ABORT |
-                                TCP_TIMEDOUT | TCP_CONNECTED);
+                                TCP_TIMEDOUT | TCP_CONNECTED | NETDEV_DOWN);
       pstate->tc_cb->priv    = (void*)pstate;
       pstate->tc_cb->event   = psock_connect_interrupt;
 
@@ -227,11 +227,20 @@ static uint16_t psock_connect_interrupt(FAR struct net_driver_s *dev,
 
       else if ((flags & TCP_TIMEDOUT) != 0)
         {
-          /* Indicate that the remote host is unreachable (or should this be timedout?) */
+          /* Indicate that the connection timedout?)*/
 
           pstate->tc_result = -ETIMEDOUT;
         }
 
+      else if ((flags & NETDEV_DOWN) != 0)
+        {
+          /* The network device went down.  Indicate that the remote host
+           * is unreachable.
+           */
+
+          pstate->tc_result = -ENETUNREACH;
+        }
+
       /* TCP_CONNECTED: The socket is successfully connected */
 
       else if ((flags & TCP_CONNECTED) != 0)

net/socket/net_close.c

@@ -167,12 +167,14 @@ static uint16_t netclose_interrupt(FAR struct net_driver_s *dev,
 
   nllvdbg("conn: %p flags: %04x\n", conn, flags);
 
-  /* TCP_CLOSE:    The remote host has closed the connection
+  /* TCP_DISCONN_EVENTS:
-   * TCP_ABORT:    The remote host has aborted the connection
+   *   TCP_CLOSE:    The remote host has closed the connection
-   * TCP_TIMEDOUT: The remote did not respond, the connection timed out
+   *   TCP_ABORT:    The remote host has aborted the connection
+   *   TCP_TIMEDOUT: The remote did not respond, the connection timed out
+   *   NETDEV_DOWN:  The network device went down
    */
 
-  if ((flags & (TCP_CLOSE | TCP_ABORT | TCP_TIMEDOUT)) != 0)
+  if ((flags & TCP_DISCONN_EVENTS) != 0)
     {
       /* The disconnection is complete */
 
@@ -371,8 +373,7 @@ static inline int netclose_disconnect(FAR struct socket *psock)
     {
       /* Set up to receive TCP data event callbacks */
 
-      state.cl_cb->flags = (TCP_NEWDATA | TCP_POLL | TCP_CLOSE | TCP_ABORT |
+      state.cl_cb->flags = (TCP_NEWDATA | TCP_POLL | TCP_DISCONN_EVENTS);
-                            TCP_TIMEDOUT);
       state.cl_cb->event = netclose_interrupt;
 
 #ifdef CONFIG_NET_SOLINGER

net/socket/net_monitor.c

@@ -89,9 +89,11 @@ static void connection_event(FAR struct tcp_conn_s *conn, uint16_t flags)
     {
       nllvdbg("flags: %04x s_flags: %02x\n", flags, psock->s_flags);
 
-      /* TCP_CLOSE, TCP_ABORT, or TCP_TIMEDOUT: Loss-of-connection events */
+      /* TCP_DISCONN_EVENTS: TCP_CLOSE, TCP_ABORT, TCP_TIMEDOUT, or
+       * NETDEV_DOWN.  All loss-of-connection events.
+       */
 
-      if ((flags & (TCP_CLOSE | TCP_ABORT | TCP_TIMEDOUT)) != 0)
+      if ((flags & TCP_DISCONN_EVENTS) != 0)
         {
           net_lostconnection(psock, flags);
         }
@@ -218,6 +220,7 @@ void net_lostconnection(FAR struct socket *psock, uint16_t flags)
    *   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
    *
    * And we need to set these two socket status bits appropriately:
    *
@@ -237,7 +240,7 @@ void net_lostconnection(FAR struct socket *psock, uint16_t flags)
       psock->s_flags &= ~_SF_CONNECTED;
       psock->s_flags |= _SF_CLOSED;
     }
-  else if ((flags & (TCP_ABORT | TCP_TIMEDOUT)) != 0)
+  else if ((flags & (TCP_ABORT | TCP_TIMEDOUT | NETDEV_DOWN)) != 0)
     {
       /* The loss of connection was less than graceful.  This will (eventually)
        * be reported as an ENOTCONN error.

net/socket/net_sendfile.c

@@ -217,7 +217,7 @@ static uint16_t ack_interrupt(FAR struct net_driver_s *dev, FAR void *pvconn,
 
   /* Check for a loss of connection */
 
-  else if ((flags & (TCP_CLOSE | TCP_ABORT | TCP_TIMEDOUT)) != 0)
+  else if ((flags & TCP_DISCONN_EVENTS) != 0)
     {
       /* Report not connected */
 
@@ -329,7 +329,7 @@ static uint16_t sendfile_interrupt(FAR struct net_driver_s *dev, FAR void *pvcon
 
   /* Check for a loss of connection */
 
-  if ((flags & (TCP_CLOSE | TCP_ABORT | TCP_TIMEDOUT)) != 0)
+  if ((flags & TCP_DISCONN_EVENTS) != 0)
     {
       /* Report not connected */
 
@@ -707,8 +707,7 @@ ssize_t net_sendfile(int outfd, struct file *infile, off_t *offset,
 
   /* Set up the ACK callback in the connection */
 
-  state.snd_ackcb->flags = (TCP_ACKDATA | TCP_REXMIT | TCP_CLOSE |
+  state.snd_ackcb->flags = (TCP_ACKDATA | TCP_REXMIT | TCP_DISCONN_EVENTS);
-                            TCP_ABORT | TCP_TIMEDOUT);
   state.snd_ackcb->priv  = (void*)&state;
   state.snd_ackcb->event = ack_interrupt;
 

net/socket/recvfrom.c

@@ -804,12 +804,14 @@ static uint16_t recvfrom_tcpinterrupt(FAR struct net_driver_s *dev,
 
       /* Check for a loss of connection.
        *
-       * TCP_CLOSE: The remote host has closed the connection
+       * TCP_DISCONN_EVENTS:
-       * TCP_ABORT: The remote host has aborted the connection
+       *   TCP_CLOSE:    The remote host has closed the connection
-       * TCP_TIMEDOUT: Connection aborted due to too many retransmissions.
+       *   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_CLOSE | TCP_ABORT | TCP_TIMEDOUT)) != 0)
+      else if ((flags & TCP_DISCONN_EVENTS) != 0)
         {
           nllvdbg("Lost connection\n");
 
@@ -1692,8 +1694,7 @@ static ssize_t tcp_recvfrom(FAR struct socket *psock, FAR void *buf, size_t len,
       state.rf_cb = tcp_callback_alloc(conn);
       if (state.rf_cb)
         {
-          state.rf_cb->flags   = (TCP_NEWDATA | TCP_POLL | TCP_CLOSE |
+          state.rf_cb->flags   = (TCP_NEWDATA | TCP_POLL | TCP_DISCONN_EVENTS);
-                                  TCP_ABORT | TCP_TIMEDOUT);
           state.rf_cb->priv    = (void*)&state;
           state.rf_cb->event   = recvfrom_tcpinterrupt;
 

net/tcp/Make.defs

@@ -55,9 +55,9 @@ endif
 
 # Transport layer
 
-NET_CSRCS += tcp_conn.c tcp_seqno.c tcp_devpoll.c tcp_timer.c tcp_send.c
+NET_CSRCS += tcp_conn.c tcp_seqno.c tcp_devpoll.c tcp_finddev.c tcp_timer.c
-NET_CSRCS += tcp_input.c tcp_appsend.c tcp_listen.c tcp_callback.c
+NET_CSRCS += tcp_send.c tcp_input.c tcp_appsend.c tcp_listen.c
-NET_CSRCS += tcp_backlog.c tcp_ipselect.c
+NET_CSRCS += tcp_callback.c tcp_backlog.c tcp_ipselect.c
 
 # TCP write buffering
 

net/tcp/tcp.h

@@ -62,8 +62,17 @@
 
 /* Allocate a new TCP data callback */
 
-#define tcp_callback_alloc(conn)   devif_callback_alloc(NULL, &conn->list)
+#ifdef CONFIG_NETDEV_MULTINIC
-#define tcp_callback_free(conn,cb) devif_callback_free(NULL, cb, &conn->list)
+#  define tcp_callback_alloc(conn) \
+    devif_callback_alloc(conn->dev, &conn->list)
+#  define tcp_callback_free(conn,cb) \
+    devif_callback_free(conn->dev, cb, &conn->list)
+#else
+#  define tcp_callback_alloc(conn) \
+    devif_callback_alloc(g_netdevices, &conn->list)
+#  define tcp_callback_free(conn,cb) \
+    devif_callback_free(g_netdevices, cb, &conn->list)
+#endif
 
 /* Get the current maximum segment size that can be sent on the current
  * TCP connection.
@@ -141,16 +150,26 @@ struct tcp_conn_s
   uint16_t unacked;       /* Number bytes sent but not yet ACKed */
 #endif
 
+#ifdef CONFIG_NETDEV_MULTINIC
+  /* If the TCP socket is bound to a local address, then this is
+   * a reference to the device that routes traffic on the corresponding
+   * network.
+   */
+
+  FAR struct net_driver_s *dev;
+#endif
+
+#ifdef CONFIG_NET_TCP_READAHEAD
   /* Read-ahead buffering.
    *
    *   readahead - A singly linked list of type struct iob_qentry_s
    *               where the TCP/IP read-ahead data is retained.
    */
 
-#ifdef CONFIG_NET_TCP_READAHEAD
   struct iob_queue_s readahead;   /* Read-ahead buffering */
 #endif
 
+#ifdef CONFIG_NET_TCP_WRITE_BUFFERS
   /* Write buffering
    *
    *   write_q   - The queue of unsent I/O buffers.  The head of this
@@ -159,7 +178,6 @@ struct tcp_conn_s
    *               chains.  Sequence number ordering.
    */
 
-#ifdef CONFIG_NET_TCP_WRITE_BUFFERS
   sq_queue_t write_q;     /* Write buffering for segments */
   sq_queue_t unacked_q;   /* Write buffering for un-ACKed segments */
   uint16_t   expired;     /* Number segments retransmitted but not yet ACKed,
@@ -168,6 +186,7 @@ struct tcp_conn_s
   uint32_t   isn;         /* Initial sequence number */
 #endif
 
+#ifdef CONFIG_NET_TCPBACKLOG
   /* Listen backlog support
    *
    *   blparent - The backlog parent.  If this connection is backlogged,
@@ -178,7 +197,6 @@ struct tcp_conn_s
    *     struct tcp_backlog_s tear-off structure that manages that backlog.
    */
 
-#ifdef CONFIG_NET_TCPBACKLOG
   FAR struct tcp_conn_s    *blparent;
   FAR struct tcp_backlog_s *backlog;
 #endif
@@ -269,6 +287,14 @@ extern "C"
 #  define EXTERN extern
 #endif
 
+#if CONFIG_NSOCKET_DESCRIPTORS > 0
+/* List of registered Ethernet device drivers.  This duplicates a declaration
+ * in net/tcp/tcp.h
+ */
+
+EXTERN struct net_driver_s *g_netdevices;
+#endif
+
 /****************************************************************************
  * Public Function Prototypes
  ****************************************************************************/
@@ -340,6 +366,46 @@ FAR struct tcp_conn_s *tcp_active(FAR struct net_driver_s *dev,
 
 FAR struct tcp_conn_s *tcp_nextconn(FAR struct tcp_conn_s *conn);
 
+/****************************************************************************
+ * Function: tcp_find_ipv4_device
+ *
+ * Description:
+ *   Select the network driver to use with the IPv4 TCP transaction.
+ *
+ * Input Parameters:
+ *   conn - TCP connection structure.  The locally bound address, laddr,
+ *     should be set to a non-zero value in this structure.
+ *
+ * Returned Value:
+ *   Zero (OK) is returned on success.  A negated errno value is returned
+ *   on failure.  -ENODEV is the only expected error value.
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_NET_IPv4
+int tcp_find_ipv4_device(FAR struct tcp_conn_s *conn);
+#endif
+
+/****************************************************************************
+ * Function: tcp_find_ipv6_device
+ *
+ * Description:
+ *   Select the network driver to use with the IPv6 TCP transaction.
+ *
+ * Input Parameters:
+ *   conn - TCP connection structure.  The locally bound address, laddr,
+ *     should be set to a non-zero value in this structure.
+ *
+ * Returned Value:
+ *   Zero (OK) is returned on success.  A negated errno value is returned
+ *   on failure.  -EHOSTUNREACH is the only expected error value.
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_NET_IPv6
+int tcp_find_ipv6_device(FAR struct tcp_conn_s *conn);
+#endif
+
 /****************************************************************************
  * Name: tcp_alloc_accept
  *

net/tcp/tcp_appsend.c

@@ -130,9 +130,22 @@ void tcp_appsend(FAR struct net_driver_s *dev, FAR struct tcp_conn_s *conn,
     }
 #endif /* CONFIG_NET_IPv6 */
 
+  /* Check If the device went down */
+
+  if ((result & NETDEV_DOWN) != 0)
+    {
+      /* If so, make sure that the connection is marked closed
+       * and do not try to send anything.
+       */
+
+      dev->d_sndlen = 0;
+      conn->tcpstateflags = TCP_CLOSED;
+      nllvdbg("TCP state: NETDEV_DOWN\n");
+    }
+
   /* Check for connection aborted */
 
-  if ((result & TCP_ABORT) != 0)
+  else if ((result & TCP_ABORT) != 0)
     {
       dev->d_sndlen = 0;
       conn->tcpstateflags = TCP_CLOSED;

net/tcp/tcp_conn.c

@@ -514,6 +514,7 @@ static inline int tcp_ipv4_bind(FAR struct tcp_conn_s *conn,
 {
   net_lock_t flags;
   int port;
+  int ret;
 
   /* Verify or select a local port and address */
 
@@ -529,21 +530,40 @@ static inline int tcp_ipv4_bind(FAR struct tcp_conn_s *conn,
   port = tcp_selectport(ntohs(addr->sin_port));
 #endif
 
-  net_unlock(flags);
-
   if (port < 0)
     {
+      ndbg("tcp_selectport failed: %d\n", port);
       return port;
     }
 
   /* Save the local address in the connection structure. */
 
   conn->lport = addr->sin_port;
-
 #ifdef CONFIG_NETDEV_MULTINIC
   net_ipv4addr_copy(conn->u.ipv4.laddr, addr->sin_addr.s_addr);
 #endif
 
+  /* Find the device that can receive packets on the network
+   * associated with this local address.
+   */
+
+  ret = tcp_find_ipv4_device(conn);
+  if (ret < 0)
+    {
+      /* If no device is found, then the address is not reachable */
+
+      ndbg("tcp_find_ipv4_device failed: %d\n", ret);
+
+      /* Back out the local address setting */
+
+      conn->lport = 0;
+#ifdef CONFIG_NETDEV_MULTINIC
+      net_ipv4addr_copy(conn->u.ipv4.laddr, INADDR_ANY);
+#endif
+      return ret;
+    }
+
+  net_unlock(flags);
   return OK;
 }
 #endif /* CONFIG_NET_IPv4 */
@@ -569,6 +589,7 @@ static inline int tcp_ipv6_bind(FAR struct tcp_conn_s *conn,
 {
   net_lock_t flags;
   int port;
+  int ret;
 
   /* Verify or select a local port and address */
 
@@ -590,21 +611,40 @@ static inline int tcp_ipv6_bind(FAR struct tcp_conn_s *conn,
   port = tcp_selectport(ntohs(addr->sin6_port));
 #endif
 
-  net_unlock(flags);
-
   if (port < 0)
     {
+      ndbg("tcp_selectport failed: %d\n", port);
       return port;
     }
 
   /* Save the local address in the connection structure. */
 
   conn->lport = addr->sin6_port;
-
 #ifdef CONFIG_NETDEV_MULTINIC
   net_ipv6addr_copy(conn->u.ipv6.laddr, addr->sin6_addr.in6_u.u6_addr16);
 #endif
 
+  /* Find the device that can receive packets on the network
+   * associated with this local address.
+   */
+
+  ret = tcp_find_ipv6_device(conn);
+  if (ret < 0)
+    {
+      /* If no device is found, then the address is not reachable */
+
+      ndbg("tcp_find_ipv6_device failed: %d\n", ret);
+
+      /* Back out the local address setting */
+
+      conn->lport = 0;
+#ifdef CONFIG_NETDEV_MULTINIC
+      net_ipv6addr_copy(conn->u.ipv6.laddr, g_ipv6_allzeroaddr);
+#endif
+      return ret;
+    }
+
+  net_unlock(flags);
   return OK;
 }
 #endif /* CONFIG_NET_IPv6 */
@@ -928,6 +968,7 @@ FAR struct tcp_conn_s *tcp_alloc_accept(FAR struct net_driver_s *dev,
 {
   FAR struct tcp_conn_s *conn;
   uint8_t domain;
+  int ret;
 
   /* Get the appropriate IP domain */
 
@@ -945,15 +986,9 @@ FAR struct tcp_conn_s *tcp_alloc_accept(FAR struct net_driver_s *dev,
   conn = tcp_alloc(domain);
   if (conn)
     {
-      /* Fill in the necessary fields for the new connection. */
+      /* Set up the local address (laddr) and the remote address (raddr)
-
+       * that describes the TCP connection.
-      conn->rto           = TCP_RTO;
+       */
-      conn->timer         = TCP_RTO;
-      conn->sa            = 0;
-      conn->sv            = 4;
-      conn->nrtx          = 0;
-      conn->lport         = tcp->destport;
-      conn->rport         = tcp->srcport;
 
 #ifdef CONFIG_NET_IPv6
 #ifdef CONFIG_NET_IPv4
@@ -962,11 +997,19 @@ FAR struct tcp_conn_s *tcp_alloc_accept(FAR struct net_driver_s *dev,
         {
           FAR struct ipv6_hdr_s *ip = IPv6BUF;
 
+          /* Set the IPv6 specific MSS and the IPv6 locally bound address */
+
           conn->mss = TCP_IPv6_INITIAL_MSS(dev);
           net_ipv6addr_copy(conn->u.ipv6.raddr, ip->srcipaddr);
 #ifdef CONFIG_NETDEV_MULTINIC
           net_ipv6addr_copy(conn->u.ipv6.laddr, ip->destipaddr);
 #endif
+
+          /* Find the device that can receive packets on the network
+           * associated with this local address.
+           */
+
+          ret = tcp_find_ipv6_device(conn);
         }
 #endif /* CONFIG_NET_IPv6 */
 
@@ -977,6 +1020,8 @@ FAR struct tcp_conn_s *tcp_alloc_accept(FAR struct net_driver_s *dev,
         {
           FAR struct ipv4_hdr_s *ip = IPv4BUF;
 
+          /* Set the IPv6 specific MSS and the IPv4 locally bound address. */
+
           conn->mss = TCP_IPv4_INITIAL_MSS(dev);
           net_ipv4addr_copy(conn->u.ipv4.raddr,
                             net_ip4addr_conv32(ip->srcipaddr));
@@ -984,9 +1029,40 @@ FAR struct tcp_conn_s *tcp_alloc_accept(FAR struct net_driver_s *dev,
           net_ipv4addr_copy(conn->u.ipv4.laddr,
                             net_ip4addr_conv32(ip->destipaddr));
 #endif
+
+          /* Find the device that can receive packets on the network
+           * associated with this local address.
+           */
+
+          ret = tcp_find_ipv4_device(conn);
         }
 #endif /* CONFIG_NET_IPv4 */
 
+      /* Verify that a network device that can provide packets to this
+       * local address was found.
+       */
+
+      if (ret < 0)
+        {
+          /* If no device is found, then the address is not reachable.
+           * That should be impossible in this context and we should
+           * probably really just assert here.
+           */
+
+          ndbg("Failed to find network device: %d\n", ret);
+          tcp_free(conn);
+          return NULL;
+        }
+
+      /* Fill in the necessary fields for the new connection. */
+
+      conn->rto           = TCP_RTO;
+      conn->timer         = TCP_RTO;
+      conn->sa            = 0;
+      conn->sv            = 4;
+      conn->nrtx          = 0;
+      conn->lport         = tcp->destport;
+      conn->rport         = tcp->srcport;
       conn->tcpstateflags = TCP_SYN_RCVD;
 
       tcp_initsequence(conn->sndseq);
@@ -1090,6 +1166,7 @@ int tcp_connect(FAR struct tcp_conn_s *conn, FAR const struct sockaddr *addr)
 {
   net_lock_t flags;
   int port;
+  int ret;
 
   /* The connection is expected to be in the TCP_ALLOCATED state.. i.e.,
    * allocated via up_tcpalloc(), but not yet put into the active connections
@@ -1153,13 +1230,80 @@ int tcp_connect(FAR struct tcp_conn_s *conn, FAR const struct sockaddr *addr)
 
 #endif /* CONFIG_NETDEV_MULTINIC */
 
-  net_unlock(flags);
-
   /* Did we have a port assignment? */
 
   if (port < 0)
     {
-      return port;
+      ret = port;
+      goto errout_with_lock;
+    }
+
+  /* Set up the local address (laddr) and the remote address (raddr) that describes the TCP connection.
+       */
+
+#ifdef CONFIG_NET_IPv4
+#ifdef CONFIG_NET_IPv6
+  if (conn->domain == PF_INET)
+#endif
+    {
+      FAR const struct sockaddr_in *inaddr =
+        (FAR const struct sockaddr_in *)addr;
+
+      /* Save MSS and the port from the sockaddr (already in network order) */
+
+      conn->mss    = MIN_IPv4_TCP_INITIAL_MSS;
+      conn->rport  = inaddr->sin_port;
+
+      /* The sockaddr address is 32-bits in network order. */
+
+      net_ipv4addr_copy(conn->u.ipv4.raddr, inaddr->sin_addr.s_addr);
+
+      /* Find the device that can receive packets on the network associated
+       * with this local address.
+       */
+
+      ret = tcp_find_ipv4_device(conn);
+    }
+#endif /* CONFIG_NET_IPv4 */
+
+#ifdef CONFIG_NET_IPv6
+#ifdef CONFIG_NET_IPv4
+  else
+#endif
+    {
+      FAR const struct sockaddr_in6 *inaddr =
+        (FAR const struct sockaddr_in6 *)addr;
+
+      /* Save MSS and the port from the sockaddr (already in network order) */
+
+      conn->mss     = MIN_IPv6_TCP_INITIAL_MSS;
+      conn->rport   = inaddr->sin6_port;
+
+      /* The sockaddr address is 128-bits in network order. */
+
+      net_ipv6addr_copy(conn->u.ipv6.raddr, inaddr->sin6_addr.s6_addr16);
+
+      /* Find the device that can receive packets on the network associated
+       * with this local address.
+       */
+
+      ret = tcp_find_ipv6_device(conn);
+    }
+#endif /* CONFIG_NET_IPv6 */
+
+  /* Verify that a network device that can provide packets to this local
+   * address was found.
+   */
+
+  if (ret < 0)
+    {
+      /* If no device is found, then the address is not reachable.  That
+       * should be impossible in this context and we should probably really
+       * just assert here.
+       */
+
+      ndbg("Failed to find network device: %d\n", ret);
+      goto errout_with_lock;
     }
 
   /* Initialize and return the connection structure, bind it to the port
@@ -1184,46 +1328,6 @@ int tcp_connect(FAR struct tcp_conn_s *conn, FAR const struct sockaddr *addr)
   conn->sent       = 0;
 #endif
 
-  /* Save values that are specific to the IP address domain */
-
-#ifdef CONFIG_NET_IPv4
-#ifdef CONFIG_NET_IPv6
-  if (conn->domain == PF_INET)
-#endif
-    {
-      FAR const struct sockaddr_in *inaddr =
-        (FAR const struct sockaddr_in *)addr;
-
-      /* Save MSS and the port from the sockaddr (already in network order) */
-
-      conn->mss    = MIN_IPv4_TCP_INITIAL_MSS;
-      conn->rport  = inaddr->sin_port;
-
-      /* The sockaddr address is 32-bits in network order. */
-
-      net_ipv4addr_copy(conn->u.ipv4.raddr, inaddr->sin_addr.s_addr);
-    }
-#endif /* CONFIG_NET_IPv4 */
-
-#ifdef CONFIG_NET_IPv6
-#ifdef CONFIG_NET_IPv4
-  else
-#endif
-    {
-      FAR const struct sockaddr_in6 *inaddr =
-        (FAR const struct sockaddr_in6 *)addr;
-
-      /* Save MSS and the port from the sockaddr (already in network order) */
-
-      conn->mss     = MIN_IPv6_TCP_INITIAL_MSS;
-      conn->rport   = inaddr->sin6_port;
-
-      /* The sockaddr address is 32-bits in network order. */
-
-      net_ipv6addr_copy(conn->u.ipv6.raddr, inaddr->sin6_addr.s6_addr16);
-    }
-#endif /* CONFIG_NET_IPv6 */
-
 #ifdef CONFIG_NET_TCP_READAHEAD
   /* Initialize the list of TCP read-ahead buffers */
 
@@ -1237,17 +1341,14 @@ int tcp_connect(FAR struct tcp_conn_s *conn, FAR const struct sockaddr *addr)
   sq_init(&conn->unacked_q);
 #endif
 
-  /* And, finally, put the connection structure into the active
+  /* And, finally, put the connection structure into the active list. */
-   * list. Because g_active_tcp_connections is accessed from user level and
-   * interrupt level, code, it is necessary to keep interrupts disabled during
-   * this operation.
-   */
 
-  flags = net_lock();
   dq_addlast(&conn->node, &g_active_tcp_connections);
-  net_unlock(flags);
+  ret = OK;
 
-  return OK;
+errout_with_lock:
+  net_unlock(flags);
+  return ret;
 }
 
 #endif /* CONFIG_NET && CONFIG_NET_TCP */

net/tcp/tcp_devpoll.c

@@ -89,7 +89,7 @@
  *   None
  *
  * Assumptions:
- *   Called from the interrupt level or with interrupts disabled.
+ *   Called with the network locked.
  *
  ****************************************************************************/
 

net/tcp/tcp_netpoll.c

@@ -119,9 +119,9 @@ static uint16_t tcp_poll_interrupt(FAR struct net_driver_s *dev, FAR void *conn,
 
       /* Check for a loss of connection events. */
 
-      if ((flags & (TCP_CLOSE | TCP_ABORT | TCP_TIMEDOUT | NETDEV_DOWN)) != 0)
+      if ((flags & TCP_DISCONN_EVENTS) != 0)
         {
-          /* Marki that the connection has been lost */
+          /* Mark that the connection has been lost */
 
           net_lostconnection(info->psock, flags);
           eventset |= (POLLERR | POLLHUP);
@@ -208,13 +208,12 @@ int tcp_pollsetup(FAR struct socket *psock, FAR struct pollfd *fds)
    * callback processing.
    */
 
-  cb->flags    = (TCP_NEWDATA | TCP_BACKLOG | TCP_POLL | TCP_CLOSE |
+  cb->flags    = (TCP_NEWDATA | TCP_BACKLOG | TCP_POLL | TCP_DISCONN_EVENTS);
-                  TCP_ABORT | TCP_TIMEDOUT | NETDEV_DOWN);
   cb->priv     = (FAR void *)info;
   cb->event    = tcp_poll_interrupt;
 
   /* Save the reference in the poll info structure as fds private as well
-   * for use durring poll teardown as well.
+   * for use during poll teardown as well.
    */
 
   fds->priv    = (FAR void *)info;

net/tcp/tcp_send_buffered.c

@@ -488,7 +488,7 @@ static uint16_t psock_send_interrupt(FAR struct net_driver_s *dev,
 
   /* Check for a loss of connection */
 
-  else if ((flags & (TCP_CLOSE | TCP_ABORT | TCP_TIMEDOUT)) != 0)
+  else if ((flags & TCP_DISCONN_EVENTS) != 0)
     {
       nllvdbg("Lost connection: %04x\n", flags);
 
@@ -1024,7 +1024,7 @@ ssize_t psock_tcp_send(FAR struct socket *psock, FAR const void *buf,
       /* Set up the callback in the connection */
 
       psock->s_sndcb->flags = (TCP_ACKDATA | TCP_REXMIT | TCP_POLL |
-                               TCP_CLOSE | TCP_ABORT | TCP_TIMEDOUT);
+                               TCP_DISCONN_EVENTS);
       psock->s_sndcb->priv  = (void*)psock;
       psock->s_sndcb->event = psock_send_interrupt;
 

net/tcp/tcp_send_unbuffered.c

@@ -376,7 +376,7 @@ static uint16_t tcpsend_interrupt(FAR struct net_driver_s *dev,
 
  /* Check for a loss of connection */
 
-  else if ((flags & (TCP_CLOSE | TCP_ABORT | TCP_TIMEDOUT)) != 0)
+  else if ((flags & TCP_DISCONN_EVENTS) != 0)
     {
       /* Report not connected */
 
@@ -810,7 +810,7 @@ ssize_t psock_tcp_send(FAR struct socket *psock,
           /* Set up the callback in the connection */
 
           state.snd_cb->flags   = (TCP_ACKDATA | TCP_REXMIT | TCP_POLL |
-                                   TCP_CLOSE | TCP_ABORT | TCP_TIMEDOUT);
+                                   TCP_DISCONN_EVENTS);
           state.snd_cb->priv    = (FAR void *)&state;
           state.snd_cb->event   = tcpsend_interrupt;
 

net/udp/udp.h

@@ -342,6 +342,7 @@ int udp_ipv6_input(FAR struct net_driver_s *dev);
  *
  * Input Parameters:
  *   conn - UDP connection structure (not currently used).
+ *   ipv4addr - The IPv4 address to use in the device selection.
  *
  * Returned Value:
  *   A pointer to the network driver to use.
@@ -361,6 +362,7 @@ FAR struct net_driver_s *udp_find_ipv4_device(FAR struct udp_conn_s *conn,
  *
  * Input Parameters:
  *   conn - UDP connection structure (not currently used).
+ *   ipv6addr - The IPv6 address to use in the device selection.
  *
  * Returned Value:
  *   A pointer to the network driver to use.

net/udp/udp_finddev.c

@@ -40,6 +40,8 @@
 #include <nuttx/config.h>
 #if defined(CONFIG_NET) && defined(CONFIG_NET_UDP)
 
+#include <string.h>
+
 #include <nuttx/net/netdev.h>
 #include <nuttx/net/ip.h>
 
@@ -66,6 +68,7 @@
  *
  * Input Parameters:
  *   conn - UDP connection structure (not currently used).
+ *   ipv4addr - The IPv4 address to use in the device selection.
  *
  * Returned Value:
  *   A pointer to the network driver to use.
@@ -77,17 +80,15 @@ FAR struct net_driver_s *udp_find_ipv4_device(FAR struct udp_conn_s *conn,
                                               in_addr_t ipv4addr)
 {
 #ifdef CONFIG_NETDEV_MULTINIC
-  FAR struct net_driver_s *dev;
+  /* Return NULL if the address is INADDR_ANY.  In this case, there may
-
+   * be multiple devices that can provide data so the exceptional events
-  /* Return NULL if the address is INADDR_ANY.  In this case, there is
+   * from any particular device are not important.
-   * there may be multiple devices that can provide data so the exceptional
-   * events from any particular device are not important.
    *
    * Of course, it would be a problem if this is the remote address of
    * sendto().
    */
 
-  if ((net_ipv4addr_cmp(ipv4addr, INADDR_ANY))
+  if (net_ipv4addr_cmp(ipv4addr, INADDR_ANY))
     {
       return NULL;
     }
@@ -99,8 +100,6 @@ FAR struct net_driver_s *udp_find_ipv4_device(FAR struct udp_conn_s *conn,
   return netdev_findby_ipv4addr(conn->u.ipv4.laddr, ipv4addr);
 
 #else
-  /* Return NULL if the address is IN6ADDR_ANY */
-
   /* There is only a single network device... the one at the head of the
    * g_netdevices list.
    */
@@ -118,6 +117,7 @@ FAR struct net_driver_s *udp_find_ipv4_device(FAR struct udp_conn_s *conn,
  *
  * Input Parameters:
  *   conn - UDP connection structure (not currently used).
+ *   ipv6addr - The IPv6 address to use in the device selection.
  *
  * Returned Value:
  *   A pointer to the network driver to use.
@@ -129,11 +129,9 @@ FAR struct net_driver_s *udp_find_ipv6_device(FAR struct udp_conn_s *conn,
                                               net_ipv6addr_t ipv6addr)
 {
 #ifdef CONFIG_NETDEV_MULTINIC
-  FAR struct net_driver_s *dev;
+  /* Return NULL if the address is IN6ADDR_ANY.  In this case, there may
-
+   * be multiple devices that can provide data so the exceptional events
-  /* Return NULL if the address is IN6ADDR_ANY.  In this case, there is
+   * from any particular device are not important.
-   * there may be multiple devices that can provide data so the exceptional
-   * events from any particular device are not important.
    *
    * Of course, it would be a problem if this is the remote address of
    * sendto().
@@ -178,8 +176,6 @@ FAR struct net_driver_s *udp_find_ipv6_device(FAR struct udp_conn_s *conn,
 FAR struct net_driver_s *udp_find_laddr_device(FAR struct udp_conn_s *conn)
 {
 #ifdef CONFIG_NETDEV_MULTINIC
-  FAR struct net_driver_s *dev;
-
   /* There are multiple network devices.  We need to select the device that
    * is going to route the UDP packet based on the provided IP address.
    */
@@ -189,7 +185,7 @@ FAR struct net_driver_s *udp_find_laddr_device(FAR struct udp_conn_s *conn)
       if (conn->domain == PF_INET)
 #endif
         {
-          return upd_find_ipv4_device(conn, conn->u.ipv4.laddr);
+          return udp_find_ipv4_device(conn, conn->u.ipv4.laddr);
         }
 #endif
 
@@ -198,7 +194,7 @@ FAR struct net_driver_s *udp_find_laddr_device(FAR struct udp_conn_s *conn)
       else
 #endif
         {
-          return upd_find_ipv6_device(conn, conn->u.ipv6.laddr);
+          return udp_find_ipv6_device(conn, conn->u.ipv6.laddr);
         }
 #endif
 
@@ -229,8 +225,6 @@ FAR struct net_driver_s *udp_find_laddr_device(FAR struct udp_conn_s *conn)
 FAR struct net_driver_s *udp_find_raddr_device(FAR struct udp_conn_s *conn)
 {
 #ifdef CONFIG_NETDEV_MULTINIC
-  FAR struct net_driver_s *dev;
-
   /* There are multiple network devices.  We need to select the device that
    * is going to route the UDP packet based on the provided IP address.
    */
@@ -240,7 +234,7 @@ FAR struct net_driver_s *udp_find_raddr_device(FAR struct udp_conn_s *conn)
       if (conn->domain == PF_INET)
 #endif
         {
-          return upd_find_ipv4_device(conn, conn->u.ipv4.raddr);
+          return udp_find_ipv4_device(conn, conn->u.ipv4.raddr);
         }
 #endif
 
@@ -249,7 +243,7 @@ FAR struct net_driver_s *udp_find_raddr_device(FAR struct udp_conn_s *conn)
       else
 #endif
         {
-          return upd_find_ipv6_device(conn, conn->u.ipv6.raddr);
+          return udp_find_ipv6_device(conn, conn->u.ipv6.raddr);
         }
 #endif