/**************************************************************************** * net/netdev/netdev_findbyaddr.c * * Copyright (C) 2007-2009, 2014 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * 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 #if defined(CONFIG_NET) && CONFIG_NSOCKET_DESCRIPTORS > 0 #include #include #include #include #include #include #include "netdev/netdev.h" #include "devif/devif.h" #include "route/route.h" /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /**************************************************************************** * Private Types ****************************************************************************/ /**************************************************************************** * Private Data ****************************************************************************/ /**************************************************************************** * Public Data ****************************************************************************/ /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Function: netdev_finddevice * * Description: * Find a previously registered network device by matching a local address * with the subnet served by the device. Only "up" devices are considered * (since a "down" device has no meaningful address). * * Parameters: * ripaddr - Remote address of a connection to use in the lookup * * Returned Value: * Pointer to driver on success; null on failure * * Assumptions: * Called from normal user mode * ****************************************************************************/ static FAR struct net_driver_s *netdev_finddevice(const net_ipaddr_t ripaddr) { FAR struct net_driver_s *dev; /* Examine each registered network device */ netdev_semtake(); for (dev = g_netdevices; dev; dev = dev->flink) { /* Is the interface in the "up" state? */ if ((dev->d_flags & IFF_UP) != 0) { /* Yes.. check for an address match (under the netmask) */ if (net_ipaddr_maskcmp(dev->d_ipaddr, ripaddr, dev->d_netmask)) { /* Its a match */ netdev_semgive(); return dev; } } } /* No device with the matching address found */ netdev_semgive(); return NULL; } /**************************************************************************** * Global Functions ****************************************************************************/ /**************************************************************************** * Function: netdev_findbyaddr * * Description: * Find a previously registered network device by matching an arbitrary * IP address. * * Parameters: * lipaddr - Local, bound address of a connection. Used only if ripaddr * is the broadcast address. Used only if CONFIG_NET_MULTILINK. * ripaddr - Remote address of a connection to use in the lookup * * Returned Value: * Pointer to driver on success; null on failure * * Assumptions: * Called from normal user mode * ****************************************************************************/ #ifdef CONFIG_NET_MULTILINK FAR struct net_driver_s *netdev_findbyaddr(const net_ipaddr_t lipaddr, const net_ipaddr_t ripaddr) #else FAR struct net_driver_s *netdev_findbyaddr(const net_ipaddr_t ripaddr) #endif { struct net_driver_s *dev; #ifdef CONFIG_NET_ROUTE net_ipaddr_t router; int ret; #endif /* First, check if this is the broadcast IP address */ if (net_ipaddr_cmp(ripaddr, g_alloneaddr)) { #ifdef CONFIG_NET_MULTILINK /* Yes.. Check the local, bound address. Is it INADDR_ANY? */ if (net_ipaddr_cmp(lipaddr, g_allzeroaddr)) { /* Yes.. In this case, I think we are supposed to send the * broadcast packet out ALL local networks. I am not sure * of that and, in any event, there is nothing we can do * about that here. */ return NULL; } else { /* Return the device associated with the local address */ return netdev_finddevice(lipaddr); } #else /* If there is only a single, registered network interface, then the * decision is pretty easy. Use that device and its default router * address. */ return g_netdevices; #endif } /* Check if the address maps to a local network */ dev = netdev_finddevice(ripaddr); if (dev) { return dev; } /* No.. The address lies on an external network */ #ifdef CONFIG_NET_ROUTE /* If we have a routing table, then perhaps we can find the local * address of a router that can forward packets to the external network. */ #ifdef CONFIG_NET_IPv6 ret = net_router(ripaddr, router); #else ret = net_router(ripaddr, &router); #endif if (ret >= 0) { /* Success... try to find the network device associated with the local * router address */ dev = netdev_finddevice(router); if (dev) { return dev; } } #endif /* CONFIG_NET_ROUTE */ /* The above lookup will fail if the packet is being sent out of our * out subnet to a router and there is no routing information. */ #ifndef CONFIG_NET_MULTILINK /* If there is only a single, registered network interface, then the * decision is pretty easy. Use that device and its default router * address. */ dev = g_netdevices; #endif /* If we will did not find the network device, then we might as well fail * because we are not configured properly to determine the route to the * destination. */ return dev; } #endif /* CONFIG_NET && CONFIG_NSOCKET_DESCRIPTORS */