apps/examples/bridge: Add a simple UDP relay bridge for testing configurations with multiple networks

4 files changed, 1007 insertions, 0 deletions

diff --git a/apps/examples/bridge/.gitignore b/apps/examples/bridge/.gitignore
new file mode 100644
index 000000000..fa1ec7579
--- /dev/null
+++ b/apps/examples/bridge/.gitignore
@@ -0,0 +1,11 @@
+/Make.dep
+/.depend
+/.built
+/*.asm
+/*.obj
+/*.rel
+/*.lst
+/*.sym
+/*.adb
+/*.lib
+/*.src
diff --git a/apps/examples/bridge/Kconfig b/apps/examples/bridge/Kconfig
new file mode 100644
index 000000000..f3ee296be
--- /dev/null
+++ b/apps/examples/bridge/Kconfig
@@ -0,0 +1,170 @@
+#
+# For a description of the syntax of this configuration file,
+# see misc/tools/kconfig-language.txt.
+#
+
+config EXAMPLES_BRIDGE
+	bool "UDP bridge example"
+	default n
+	depends on NET_UDP && NETDEV_MULTINIC && !NET_IPv6
+	---help---
+		Simple test of a system with multiple networks.  It simply echoes all
+		UDP packets received on network 1 and network 2 to network 2 and
+		network 1, respectively.  Interface 1 and interface may or may not
+		lie on the same network.
+
+		If used as a NSH add-on, then it is assumed that initialization of
+		both networks was performed externally prior to the time that this
+		test was started.
+
+if EXAMPLES_BRIDGE
+
+comment "Network 1 configuration"
+
+config EXAMPLES_BRIDGE_NET1_IFNAME
+	string "Device name"
+	default "eth0"
+	---help---
+		The register name of the network 1 device.  Must match the previously
+		registered driver name and must not be the same as
+		EXAMPLES_BRIDGE_NET2_IFNAME
+
+config EXAMPLES_BRIDGE_NET1_RECVPORT
+	int "UDP receive port"
+	default 5471
+	---help---
+		Network 1 listen port number
+
+config EXAMPLES_BRIDGE_NET1_SNDPORT
+	int "UDP send port"
+	default 5472
+	---help---
+		Network 2 send port number
+
+config EXAMPLES_BRIDGE_NET1_IOBUFIZE
+	int "UDP I/O buffer size"
+	default 1024
+	---help---
+		Size of the UDP send/receive I/O buffer
+
+if !NSH_BUILTIN_APPS
+
+config EXAMPLES_BRIDGE_NET1_DHCPC
+	bool "DHCP Client"
+	default n
+	select NETUTILS_DHCPC
+	select NETUTILS_DNSCLIENT
+
+config EXAMPLES_BRIDGE_NET1_NOMAC
+	bool "Use Canned MAC Address"
+	default n
+	---help---
+		Select if the hardware has no built-in MAC address.
+
+config EXAMPLES_BRIDGE_NET1_MACADDR
+	hex "Canned MAC address"
+	default 0x00e0deadbeef
+	depends on EXAMPLES_BRIDGE_NET1_NOMAC
+	---help---
+		If the hardware has no built-in MAC address then the fixed,
+		software-assigned MAC address MAC address must provided
+		with this selection.
+
+config EXAMPLES_BRIDGE_NET1_IPADDR
+	hex "IP address"
+	default 0x0a000002
+	depends on !EXAMPLES_BRIDGE_NET1_DHCPC
+
+config EXAMPLES_BRIDGE_NET1_DRIPADDR
+	hex "Default Router IP address (Gateway)"
+	default 0x0a000001
+
+config EXAMPLES_BRIDGE_NET1_NETMASK
+	hex "Network Mask"
+	default 0xffffff00
+
+endif # !NSH_BUILTIN_APPS
+
+config EXAMPLES_BRIDGE_NET1_STACKSIZE
+	int "Network 1 daemon stacksize"
+	default 2048
+
+config EXAMPLES_BRIDGE_NET1_PRIORITY
+	int "Network 1 daemon task priority"
+	default 100
+
+comment "Network 2 configuration"
+
+config EXAMPLES_BRIDGE_NET2_IFNAME
+	string "Device name"
+	default "eth1"
+	---help---
+		The register name of the network 2 device.  Must match the previously
+		registered driver name and must not be the same as
+		EXAMPLES_BRIDGE_NET2_IFNAME
+
+config EXAMPLES_BRIDGE_NET2_RECVPORT
+	int "UDP receive port"
+	default 5471
+	---help---
+		Network 1 listen port number
+
+config EXAMPLES_BRIDGE_NET2_SNDPORT
+	int "UDP send port"
+	default 5472
+	---help---
+		Network 2 send port number
+
+config EXAMPLES_BRIDGE_NET2_IOBUFIZE
+	int "UDP I/O buffer size"
+	default 1024
+	---help---
+		Size of the UDP send/receive I/O buffer
+
+if !NSH_BUILTIN_APPS
+
+config EXAMPLES_BRIDGE_NET2_DHCPC
+	bool "DHCP Client"
+	default n
+	select NETUTILS_DHCPC
+	select NETUTILS_DNSCLIENT
+
+config EXAMPLES_BRIDGE_NET2_NOMAC
+	bool "Use Canned MAC Address"
+	default n
+	---help---
+		Select if the hardware has no built-in MAC address.
+
+config EXAMPLES_BRIDGE_NET2_MACADDR
+	hex "Canned MAC address"
+	default 0x00e0f00dface
+	depends on EXAMPLES_BRIDGE_NET2_NOMAC
+	---help---
+		If the hardware has no built-in MAC address then the fixed,
+		software-assigned MAC address MAC address must provided
+		with this selection.
+
+config EXAMPLES_BRIDGE_NET2_IPADDR
+	hex "IP address"
+	default 0x0a000003
+	depends on !EXAMPLES_BRIDGE_NET2_DHCPC
+
+config EXAMPLES_BRIDGE_NET2_DRIPADDR
+	hex "Default Router IP address (Gateway)"
+	default 0x0a000001
+
+config EXAMPLES_BRIDGE_NET2_NETMASK
+	hex "Network Mask"
+	default 0xffffff00
+
+endif # !NSH_BUILTIN_APPS
+
+config EXAMPLES_BRIDGE_NET2_STACKSIZE
+	int "Network 2 daemon stacksize"
+	default 2048
+
+config EXAMPLES_BRIDGE_NET2_PRIORITY
+	int "Network 2 daemon task priority"
+	default 100
+
+endif # EXAMPLES_BRIDGE
diff --git a/apps/examples/bridge/Makefile b/apps/examples/bridge/Makefile
new file mode 100644
index 000000000..62521e46c
--- /dev/null
+++ b/apps/examples/bridge/Makefile
@@ -0,0 +1,136 @@
+############################################################################
+# apps/examples/bridge/Makefile
+#
+#   Copyright (C) 2014 Gregory Nutt. All rights reserved.
+#
+#   Authors: 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.
+#
+############################################################################
+
+-include $(TOPDIR)/.config
+-include $(TOPDIR)/Make.defs
+include $(APPDIR)/Make.defs
+
+# Discover built-in application info
+
+APPNAME = bridge
+PRIORITY = SCHED_PRIORITY_DEFAULT
+STACKSIZE = 2048
+
+ASRCS =
+CSRCS =
+MAINSRC = bridge_main.c
+
+AOBJS = $(ASRCS:.S=$(OBJEXT))
+COBJS = $(CSRCS:.c=$(OBJEXT))
+MAINOBJ = $(MAINSRC:.c=$(OBJEXT))
+
+SRCS = $(ASRCS) $(CSRCS) $(MAINSRC)
+OBJS = $(AOBJS) $(COBJS)
+
+ifneq ($(CONFIG_BUILD_KERNEL),y)
+  OBJS += $(MAINOBJ)
+endif
+
+ifeq ($(CONFIG_WINDOWS_NATIVE),y)
+  BIN = ..\..\libapps$(LIBEXT)
+else
+ifeq ($(WINTOOL),y)
+  BIN = ..\\..\\libapps$(LIBEXT)
+else
+  BIN = ../../libapps$(LIBEXT)
+endif
+endif
+
+ifeq ($(WINTOOL),y)
+  INSTALL_DIR = "${shell cygpath -w $(BIN_DIR)}"
+else
+  INSTALL_DIR = $(BIN_DIR)
+endif
+
+CONFIG_EXAMPLE_BRIDGE_PROGNAME ?= bridge$(EXEEXT)
+PROGNAME = $(CONFIG_EXAMPLE_BRIDGE_PROGNAME)
+
+ROOTDEPPATH = --dep-path .
+
+# Common build
+
+VPATH =
+
+all: .built
+.PHONY: clean depend distclean
+
+$(AOBJS): %$(OBJEXT): %.S
+	$(call ASSEMBLE, $<, $@)
+
+$(COBJS) $(MAINOBJ): %$(OBJEXT): %.c
+	$(call COMPILE, $<, $@)
+
+.built: $(OBJS)
+	$(call ARCHIVE, $(BIN), $(OBJS))
+	@touch .built
+
+ifeq ($(CONFIG_BUILD_KERNEL),y)
+$(BIN_DIR)$(DELIM)$(PROGNAME): $(OBJS) $(MAINOBJ)
+	@echo "LD: $(PROGNAME)"
+	$(Q) $(LD) $(LDELFFLAGS) $(LDLIBPATH) -o $(INSTALL_DIR)$(DELIM)$(PROGNAME) $(ARCHCRT0OBJ) $(MAINOBJ) $(LDLIBS)
+	$(Q) $(NM) -u  $(INSTALL_DIR)$(DELIM)$(PROGNAME)
+
+install: $(BIN_DIR)$(DELIM)$(PROGNAME)
+
+else
+install:
+
+endif
+
+ifeq ($(CONFIG_NSH_BUILTIN_APPS),y)
+$(BUILTIN_REGISTRY)$(DELIM)$(APPNAME)_main.bdat: $(DEPCONFIG) Makefile
+	$(call REGISTER,$(APPNAME),$(PRIORITY),$(STACKSIZE),$(APPNAME)_main)
+
+context: $(BUILTIN_REGISTRY)$(DELIM)$(APPNAME)_main.bdat
+else
+context:
+endif
+
+.depend: Makefile $(SRCS)
+	@$(MKDEP) $(ROOTDEPPATH) "$(CC)" -- $(CFLAGS) -- $(SRCS) >Make.dep
+	@touch $@
+
+depend: .depend
+
+clean:
+	$(call DELFILE, .built)
+	$(call CLEAN)
+
+distclean: clean
+	$(call DELFILE, Make.dep)
+	$(call DELFILE, .depend)
+
+-include Make.dep
diff --git a/apps/examples/bridge/bridge_main.c b/apps/examples/bridge/bridge_main.c
new file mode 100644
index 000000000..b7062f643
--- /dev/null
+++ b/apps/examples/bridge/bridge_main.c
@@ -0,0 +1,690 @@
+/****************************************************************************
+ * examples/bridge/bridge_main.c
+ *
+ *   Copyright (C) 2014 Gregory Nutt. All rights reserved.
+ *
+ *   Authors: 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 <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sched.h>
+#include <errno.h>
+#include <debug.h>
+
+#include <net/if.h>
+#include <arpa/inet.h>
+#include <netinet/in.h>
+
+#include <nuttx/net/arp.h>
+#include <apps/netutils/netlib.h>
+
+#if defined(CONFIG_EXAMPLES_BRIDGE_NET1_DHCPC) || \
+    defined(CONFIG_EXAMPLES_BRIDGE_NET2_DHCPC)
+#  include <arpa/inet.h>
+#  include <apps/netutils/dnsclient.h>
+#  include <apps/netutils/dhcpc.h>
+#endif
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+#define BRIDGE_MAXLINE 64
+#define BRIDGE_POLLTIMEOUT 10000
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+static in_addr_t g_net1_ipaddr;
+static in_addr_t g_net2_ipaddr;
+static uint8_t g_net1_buffer[CONFIG_EXAMPLES_BRIDGE_NET1_IOBUFIZE];
+static uint8_t g_net2_buffer[CONFIG_EXAMPLES_BRIDGE_NET2_IOBUFIZE];
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: briget_net1_setup
+ ****************************************************************************/
+
+static int briget_net1_setup(void)
+{
+  /* If this task is executed as an NSH built-in function, then the
+   * network has already been configured by NSH's start-up logic.
+   */
+
+#ifndef CONFIG_NSH_BUILTIN_APPS
+  struct in_addr addr;
+#if defined(CONFIG_EXAMPLES_BRIDGE_NET1_DHCPC) || \
+    defined(CONFIG_EXAMPLES_BRIDGE_NET1_NOMAC)
+  uint8_t mac[IFHWADDRLEN];
+#endif
+#ifdef CONFIG_EXAMPLES_BRIDGE_NET1_DHCPC
+  struct dhcpc_state ds;
+  void *handle;
+#endif
+
+printf("NET1: Configuring %s\n", CONFIG_EXAMPLES_BRIDGE_NET1_IFNAME);
+
+/* Many embedded network interfaces must have a software assigned MAC */
+
+#ifdef CONFIG_EXAMPLES_BRIDGE_NET1_NOMAC
+  mac[0] = (CONFIG_EXAMPLES_BRIDGE_NET1_MACADDR >> (8 * 5)) & 0xff;
+  mac[1] = (CONFIG_EXAMPLES_BRIDGE_NET1_MACADDR >> (8 * 4)) & 0xff;
+  mac[2] = (CONFIG_EXAMPLES_BRIDGE_NET1_MACADDR >> (8 * 3)) & 0xff;
+  mac[3] = (CONFIG_EXAMPLES_BRIDGE_NET1_MACADDR >> (8 * 2)) & 0xff;
+  mac[4] = (CONFIG_EXAMPLES_BRIDGE_NET1_MACADDR >> (8 * 1)) & 0xff;
+  mac[5] = (CONFIG_EXAMPLES_BRIDGE_NET1_MACADDR >> (8 * 0)) & 0xff;
+  netlib_setmacaddr(CONFIG_EXAMPLES_BRIDGE_NET1_IFNAME, mac);
+#endif
+
+  /* Set up our host address */
+
+#ifdef CONFIG_EXAMPLES_BRIDGE_NET1_DHCPC
+  addr.s_addr = 0;
+#else
+  addr.s_addr = HTONL(CONFIG_EXAMPLES_BRIDGE_NET1_IPADDR);
+#endif
+  netlib_sethostaddr(CONFIG_EXAMPLES_BRIDGE_NET1_IFNAME, &addr);
+
+  /* Set up the default router address */
+
+  addr.s_addr = HTONL(CONFIG_EXAMPLES_BRIDGE_NET1_DRIPADDR);
+  netlib_setdraddr(CONFIG_EXAMPLES_BRIDGE_NET1_IFNAME, &addr);
+
+  /* Setup the subnet mask */
+
+  addr.s_addr = HTONL(CONFIG_EXAMPLES_BRIDGE_NET1_NETMASK);
+  netlib_setnetmask(CONFIG_EXAMPLES_BRIDGE_NET1_IFNAME, &addr);
+
+#ifdef CONFIG_EXAMPLES_BRIDGE_NET1_DHCPC
+  /* Set up the resolver */
+
+  dns_bind();
+
+  /* Get the MAC address of the NIC */
+
+  netlib_getmacaddr(CONFIG_EXAMPLES_BRIDGE_NET1_IFNAME, mac);
+
+  /* Set up the DHCPC modules */
+
+  handle = dhcpc_open(&mac, IFHWADDRLEN);
+
+  /* Get an IP address.  Note:  there is no logic here for renewing the address in this
+   * example.  The address should be renewed in ds.lease_time/2 seconds.
+   */
+
+  if (!handle)
+    {
+      fprintf(stderr, "NET1 ERROR: dhcpc_open failed\n");
+      return ERROR;
+    }
+
+  if (dhcpc_request(handle, &ds) != OK)
+    {
+      fprintf(stderr, "NET1 ERROR: dhcpc_request failed\n");
+      return ERROR;
+    }
+
+  netlib_sethostaddr(CONFIG_EXAMPLES_BRIDGE_NET1_IFNAME, &ds.ipaddr);
+
+  if (ds.netmask.s_addr != 0)
+    {
+      netlib_setnetmask(CONFIG_EXAMPLES_BRIDGE_NET1_IFNAME, &ds.netmask);
+    }
+
+  if (ds.default_router.s_addr != 0)
+    {
+      netlib_setdraddr(CONFIG_EXAMPLES_BRIDGE_NET1_IFNAME, &ds.default_router);
+    }
+
+  if (ds.dnsaddr.s_addr != 0)
+    {
+      dns_setserver(&ds.dnsaddr);
+    }
+
+  dhcpc_close(handle);
+  printf("NET1: Assigned IP: %s\n", inet_ntoa(ds.ipaddr));
+
+  /* Save the IP address in network order */
+
+  g_net1_ipaddr = ds.ipaddr;
+
+#else
+  /* Save the IP address in network order */
+
+  g_net1_ipaddr = HTONL(CONFIG_EXAMPLES_BRIDGE_NET1_IPADDR);
+
+#endif /* CONFIG_EXAMPLES_BRIDGE_NET1_DHCPC */
+#endif /* CONFIG_NSH_BUILTIN_APPS */
+
+  return OK;
+}
+
+/****************************************************************************
+ * Name: briget_net2_setup
+ ****************************************************************************/
+
+static int briget_net2_setup(void)
+{
+  /* If this task is executed as an NSH built-in function, then the
+   * network has already been configured by NSH's start-up logic.
+   */
+
+#ifndef CONFIG_NSH_BUILTIN_APPS
+  struct in_addr addr;
+#if defined(CONFIG_EXAMPLES_BRIDGE_NET2_DHCPC) || \
+    defined(CONFIG_EXAMPLES_BRIDGE_NET2_NOMAC)
+  uint8_t mac[IFHWADDRLEN];
+#endif
+#ifdef CONFIG_EXAMPLES_BRIDGE_NET2_DHCPC
+  struct dhcpc_state ds;
+  void *handle;
+#endif
+
+printf("NET2: Configuring %s\n", CONFIG_EXAMPLES_BRIDGE_NET2_IFNAME);
+
+/* Many embedded network interfaces must have a software assigned MAC */
+
+#ifdef CONFIG_EXAMPLES_BRIDGE_NET2_NOMAC
+  mac[0] = (CONFIG_EXAMPLES_BRIDGE_NET2_MACADDR >> (8 * 5)) & 0xff;
+  mac[1] = (CONFIG_EXAMPLES_BRIDGE_NET2_MACADDR >> (8 * 4)) & 0xff;
+  mac[2] = (CONFIG_EXAMPLES_BRIDGE_NET2_MACADDR >> (8 * 3)) & 0xff;
+  mac[3] = (CONFIG_EXAMPLES_BRIDGE_NET2_MACADDR >> (8 * 2)) & 0xff;
+  mac[4] = (CONFIG_EXAMPLES_BRIDGE_NET2_MACADDR >> (8 * 1)) & 0xff;
+  mac[5] = (CONFIG_EXAMPLES_BRIDGE_NET2_MACADDR >> (8 * 0)) & 0xff;
+  netlib_setmacaddr(CONFIG_EXAMPLES_BRIDGE_NET2_IFNAME, mac);
+#endif
+
+  /* Set up our host address */
+
+#ifdef CONFIG_EXAMPLES_BRIDGE_NET2_DHCPC
+  addr.s_addr = 0;
+#else
+  addr.s_addr = HTONL(CONFIG_EXAMPLES_BRIDGE_NET2_IPADDR);
+#endif
+  netlib_sethostaddr(CONFIG_EXAMPLES_BRIDGE_NET2_IFNAME, &addr);
+
+  /* Set up the default router address */
+
+  addr.s_addr = HTONL(CONFIG_EXAMPLES_BRIDGE_NET2_DRIPADDR);
+  netlib_setdraddr(CONFIG_EXAMPLES_BRIDGE_NET2_IFNAME, &addr);
+
+  /* Setup the subnet mask */
+
+  addr.s_addr = HTONL(CONFIG_EXAMPLES_BRIDGE_NET2_NETMASK);
+  netlib_setnetmask(CONFIG_EXAMPLES_BRIDGE_NET2_IFNAME, &addr);
+
+#ifdef CONFIG_EXAMPLES_BRIDGE_NET2_DHCPC
+  /* Set up the resolver */
+
+  dns_bind();
+
+  /* Get the MAC address of the NIC */
+
+  netlib_getmacaddr(CONFIG_EXAMPLES_BRIDGE_NET2_IFNAME, mac);
+
+  /* Set up the DHCPC modules */
+
+  handle = dhcpc_open(&mac, IFHWADDRLEN);
+
+  /* Get an IP address.  Note:  there is no logic here for renewing the address in this
+   * example.  The address should be renewed in ds.lease_time/2 seconds.
+   */
+
+  if (!handle)
+    {
+      fprintf(stderr, "NET2 ERROR: dhcpc_open failed\n");
+      return ERROR;
+    }
+
+  if (dhcpc_request(handle, &ds) != OK)
+    {
+      fprintf(stderr, "NET2 ERROR: dhcpc_request failed\n");
+      return ERROR;
+    }
+
+  netlib_sethostaddr(CONFIG_EXAMPLES_BRIDGE_NET2_IFNAME, &ds.ipaddr);
+
+  if (ds.netmask.s_addr != 0)
+    {
+      netlib_setnetmask(CONFIG_EXAMPLES_BRIDGE_NET2_IFNAME, &ds.netmask);
+    }
+
+  if (ds.default_router.s_addr != 0)
+    {
+      netlib_setdraddr(CONFIG_EXAMPLES_BRIDGE_NET2_IFNAME, &ds.default_router);
+    }
+
+  if (ds.dnsaddr.s_addr != 0)
+    {
+      dns_setserver(&ds.dnsaddr);
+    }
+
+  dhcpc_close(handle);
+  printf("NET1: Assigned IP: %s\n", inet_ntoa(ds.ipaddr));
+
+  /* Save the IP address in network order */
+
+  g_net2_ipaddr = ds.ipaddr;
+
+#else
+  /* Save the IP address in network order */
+
+  g_net2_ipaddr = HTONL(CONFIG_EXAMPLES_BRIDGE_NET2_IPADDR);
+
+#endif /* CONFIG_EXAMPLES_BRIDGE_NET2_DHCPC */
+#endif /* CONFIG_NSH_BUILTIN_APPS */
+
+  return OK;
+}
+
+/****************************************************************************
+ * Name: bridge_net1_worker
+ ****************************************************************************/
+
+static int bridge_net1_worker(int argc, char *argv[])
+{
+  struct sockaddr_in recvaddr;
+  struct sockaddr_in listenaddr;
+  struct sockaddr_in sendaddr;
+  socklen_t addrlen;
+  in_addr_t tmpaddr;
+  ssize_t nrecvd;
+  ssize_t nsent;
+  int optval;
+  int recvsd;
+  int sndsd;
+
+  printf("NET1: Worker started.  PID=%d\n", getpid());
+
+  /* Create a UDP receive socket on network 1 */
+
+  printf("NET1: Create receive socket\n");
+
+  recvsd = socket(PF_INET, SOCK_DGRAM, 0);
+  if (recvsd < 0)
+    {
+      fprintf(stderr, "NET1 ERROR: Failed to create receive socket: %d\n", errno);
+      return EXIT_FAILURE;
+    }
+
+  /* Set socket to reuse address */
+
+  optval = 1;
+  if (setsockopt(recvsd, SOL_SOCKET, SO_REUSEADDR, (void*)&optval, sizeof(int)) < 0)
+    {
+      fprintf(stderr, "NET1 ERROR: setsockopt SO_REUSEADDR failure: %d\n", errno);
+      goto errout_with_recvsd;
+    }
+
+  /* Bind the socket to a local address */
+
+  listenaddr.sin_family      = AF_INET;
+  listenaddr.sin_port        = HTONS(CONFIG_EXAMPLES_BRIDGE_NET1_RECVPORT);
+  listenaddr.sin_addr.s_addr = g_net1_ipaddr;
+
+  if (bind(recvsd, (struct sockaddr*)&listenaddr, sizeof(struct sockaddr_in)) < 0)
+    {
+      fprintf(stderr, "NET1 ERROR: bind failure: %d\n", errno);
+      goto errout_with_recvsd;
+    }
+
+  /* Create a UDP send socket on network 2 */
+
+  printf("NET1: Create send socket\n");
+
+  sndsd = socket(PF_INET, SOCK_DGRAM, 0);
+  if (sndsd < 0)
+    {
+      fprintf(stderr, "NET1 ERROR: Failed to create send socket: %d\n", errno);
+      goto errout_with_recvsd;
+    }
+
+  /* Set socket to reuse address */
+
+  optval = 1;
+  if (setsockopt(sndsd, SOL_SOCKET, SO_REUSEADDR, (void*)&optval, sizeof(int)) < 0)
+    {
+      fprintf(stderr, "NET1 ERROR: setsockopt SO_REUSEADDR failure: %d\n", errno);
+      goto errout_with_sendsd;
+    }
+
+  /* Bind the socket to a local address */
+
+  sendaddr.sin_family      = AF_INET;
+  sendaddr.sin_port        = HTONS(CONFIG_EXAMPLES_BRIDGE_NET1_SNDPORT);
+  sendaddr.sin_addr.s_addr = g_net2_ipaddr;
+
+  if (bind(sndsd, (struct sockaddr*)&sendaddr, sizeof(struct sockaddr_in)) < 0)
+    {
+      printf("NET1: bind failure: %d\n", errno);
+      goto errout_with_sendsd;
+    }
+
+  /* Then receive and forward UDP packets forever  */
+
+  for (;;)
+    {
+      /* Read a packet on network 1 */
+
+      printf("NET1: Receiving up to %d bytes on network 1\n",
+             CONFIG_EXAMPLES_BRIDGE_NET1_IOBUFIZE);
+
+      addrlen = sizeof(struct sockaddr_in);
+      nrecvd = recvfrom(recvsd, g_net1_buffer, CONFIG_EXAMPLES_BRIDGE_NET1_IOBUFIZE, 0,
+                        (FAR struct sockaddr*)&recvaddr, &addrlen);
+
+      tmpaddr = ntohl(recvaddr.sin_addr.s_addr);
+      printf("NET1: Received %d bytes from %d.%d.%d.%d:%d\n",
+             nrecvd,
+             tmpaddr >> 24, (tmpaddr >> 16) & 0xff,
+             (tmpaddr >> 8) & 0xff, tmpaddr & 0xff,
+             ntohs(recvaddr.sin_port));
+
+      /* Check for a receive error or zero bytes received.  The negative
+       * return value indicates a receive error; Zero would mean that the
+       * other side of the "connection" performed an "orderly" shutdown.
+       * This should not occur with a UDP socket and so must also be an
+       * error of some kind.
+       */
+
+      if (nrecvd <= 0)
+        {
+          if (nrecvd < 0)
+            {
+              fprintf(stderr, "NET1 ERROR: recvfrom failed: %d\n", errno);
+            }
+          else
+            {
+              fprintf(stderr, "NET1 ERROR: recvfrom returned zero\n");
+            }
+
+          goto errout_with_sendsd;
+        }
+
+      /* Send the newly received packet out network 2 */
+
+      printf("NET1: Sending %d bytes on network 2\n", nrecvd);
+      nsent = sendto(sndsd, g_net1_buffer, nrecvd, 0,
+                      (struct sockaddr*)&sendaddr, sizeof(struct sockaddr_in));
+
+      /* Check for send errors */
+
+      if (nsent < 0)
+        {
+          fprintf(stderr, "NET1 ERROR: sendto failed: %d\n", errno);
+          goto errout_with_sendsd;
+        }
+      else if (nsent != nrecvd)
+        {
+          fprintf(stderr, "NET1 ERROR: Bad send length: %d Expected: %d\n",
+                 nsent, nrecvd);
+          goto errout_with_sendsd;
+        }
+    }
+
+  close(recvsd);
+  close(recvsd);
+  return EXIT_SUCCESS;
+
+errout_with_sendsd:
+   close(sndsd);
+errout_with_recvsd:
+   close(recvsd);
+   return EXIT_FAILURE;
+}
+
+/****************************************************************************
+ * Name: bridge_net2_worker
+ ****************************************************************************/
+
+static int bridge_net2_worker(int argc, char *argv[])
+{
+  struct sockaddr_in recvaddr;
+  struct sockaddr_in listenaddr;
+  struct sockaddr_in sendaddr;
+  socklen_t addrlen;
+  in_addr_t tmpaddr;
+  ssize_t nrecvd;
+  ssize_t nsent;
+  int optval;
+  int recvsd;
+  int sndsd;
+
+  printf("NET2: Worker started.  PID=%d\n", getpid());
+
+  /* Create a UDP receive socket on network 2 */
+
+  printf("NET2: Create receive socket\n");
+
+  recvsd = socket(PF_INET, SOCK_DGRAM, 0);
+  if (recvsd < 0)
+    {
+      fprintf(stderr, "NET2 ERROR: Failed to create receive socket: %d\n", errno);
+      return EXIT_FAILURE;
+    }
+
+  /* Set socket to reuse address */
+
+  optval = 1;
+  if (setsockopt(recvsd, SOL_SOCKET, SO_REUSEADDR, (void*)&optval, sizeof(int)) < 0)
+    {
+      fprintf(stderr, "NET2 ERROR: setsockopt SO_REUSEADDR failure: %d\n", errno);
+      goto errout_with_recvsd;
+    }
+
+  /* Bind the socket to a local address */
+
+  listenaddr.sin_family      = AF_INET;
+  listenaddr.sin_port        = HTONS(CONFIG_EXAMPLES_BRIDGE_NET2_RECVPORT);
+  listenaddr.sin_addr.s_addr = g_net2_ipaddr;
+
+  if (bind(recvsd, (struct sockaddr*)&listenaddr, sizeof(struct sockaddr_in)) < 0)
+    {
+      fprintf(stderr, "NET2 ERROR: bind failure: %d\n", errno);
+      goto errout_with_recvsd;
+    }
+
+  /* Create a UDP send socket on network 1 */
+
+  printf("NET2: Create send socket\n");
+
+  sndsd = socket(PF_INET, SOCK_DGRAM, 0);
+  if (sndsd < 0)
+    {
+      fprintf(stderr, "NET2 ERROR: Failed to create send socket: %d\n", errno);
+      goto errout_with_recvsd;
+    }
+
+  /* Set socket to reuse address */
+
+  optval = 1;
+  if (setsockopt(sndsd, SOL_SOCKET, SO_REUSEADDR, (void*)&optval, sizeof(int)) < 0)
+    {
+      fprintf(stderr, "NET2 ERROR: setsockopt SO_REUSEADDR failure: %d\n", errno);
+      goto errout_with_sendsd;
+    }
+
+  /* Bind the socket to a local address */
+
+  sendaddr.sin_family      = AF_INET;
+  sendaddr.sin_port        = HTONS(CONFIG_EXAMPLES_BRIDGE_NET2_SNDPORT);
+  sendaddr.sin_addr.s_addr = g_net1_ipaddr;
+
+  if (bind(sndsd, (struct sockaddr*)&sendaddr, sizeof(struct sockaddr_in)) < 0)
+    {
+      printf("NET2: bind failure: %d\n", errno);
+      goto errout_with_sendsd;
+    }
+
+  /* Then receive and forward UDP packets forever  */
+
+  for (;;)
+    {
+      /* Read a packet on network 2 */
+
+      printf("NET2: Receiving up to %d bytes on network 2\n",
+             CONFIG_EXAMPLES_BRIDGE_NET2_IOBUFIZE);
+
+      addrlen = sizeof(struct sockaddr_in);
+      nrecvd = recvfrom(recvsd, g_net2_buffer, CONFIG_EXAMPLES_BRIDGE_NET2_IOBUFIZE, 0,
+                        (FAR struct sockaddr*)&recvaddr, &addrlen);
+
+      tmpaddr = ntohl(recvaddr.sin_addr.s_addr);
+      printf("NET2: Received %d bytes from %d.%d.%d.%d:%d\n",
+             nrecvd,
+             tmpaddr >> 24, (tmpaddr >> 16) & 0xff,
+             (tmpaddr >> 8) & 0xff, tmpaddr & 0xff,
+             ntohs(recvaddr.sin_port));
+
+      /* Check for a receive error or zero bytes received.  The negative
+       * return value indicates a receive error; Zero would mean that the
+       * other side of the "connection" performed an "orderly" shutdown.
+       * This should not occur with a UDP socket and so must also be an
+       * error of some kind.
+       */
+
+      if (nrecvd <= 0)
+        {
+          if (nrecvd < 0)
+            {
+              fprintf(stderr, "NET2 ERROR: recvfrom failed: %d\n", errno);
+            }
+          else
+            {
+              fprintf(stderr, "NET2 ERROR: recvfrom returned zero\n");
+            }
+
+          goto errout_with_sendsd;
+        }
+
+      /* Send the newly received packet out network 1 */
+
+      printf("NET2: Sending %d bytes on network 1\n", nrecvd);
+      nsent = sendto(sndsd, g_net2_buffer, nrecvd, 0,
+                      (struct sockaddr*)&sendaddr, sizeof(struct sockaddr_in));
+
+      /* Check for send errors */
+
+      if (nsent < 0)
+        {
+          fprintf(stderr, "NET2 ERROR: sendto failed: %d\n", errno);
+          goto errout_with_sendsd;
+        }
+      else if (nsent != nrecvd)
+        {
+          fprintf(stderr, "NET2 ERROR: Bad send length: %d Expected: %d\n",
+                 nsent, nrecvd);
+          goto errout_with_sendsd;
+        }
+    }
+
+  close(recvsd);
+  close(recvsd);
+  return EXIT_SUCCESS;
+
+errout_with_sendsd:
+   close(sndsd);
+errout_with_recvsd:
+   close(recvsd);
+   return EXIT_FAILURE;
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * bridge_main
+ ****************************************************************************/
+
+#ifdef CONFIG_BUILD_KERNEL
+int main(int argc, FAR char *argv[])
+#else
+int bridge_main(int argc, char *argv[])
+#endif
+{
+  pid_t net1_worker;
+  pid_t net2_worker;
+  int ret;
+
+  /* Initialize networks */
+
+  ret = briget_net1_setup();
+  if (ret != OK)
+    {
+      fprintf(stderr, "ERROR: Failed to setup network 1\n");
+      return EXIT_FAILURE;
+    }
+
+  ret = briget_net2_setup();
+  if (ret != OK)
+    {
+      fprintf(stderr, "ERROR: Failed to setup network 2\n");
+      return EXIT_FAILURE;
+    }
+
+  /* Start network daemons */
+
+  printf("Start network 1 worker\n");
+
+  net1_worker = task_create("NET1 Worker", CONFIG_EXAMPLES_BRIDGE_NET1_PRIORITY,
+                        CONFIG_EXAMPLES_BRIDGE_NET1_STACKSIZE, bridge_net1_worker,
+                        NULL);
+  if (net1_worker < 0)
+    {
+      fprintf(stderr, "ERROR: Failed to start network daemon 1\n");
+      return EXIT_FAILURE;
+    }
+
+  printf("Start network 2 worker\n");
+
+  net2_worker = task_create("NET2 Worker", CONFIG_EXAMPLES_BRIDGE_NET2_PRIORITY,
+                        CONFIG_EXAMPLES_BRIDGE_NET2_STACKSIZE, bridge_net2_worker,
+                        NULL);
+  if (net2_worker < 0)
+    {
+      fprintf(stderr, "ERROR: Failed to start network daemon 2\n");
+      return EXIT_FAILURE;
+    }
+
+  return EXIT_SUCCESS;
+}
+