| /**************************************************************************** |
| * net/netdev/netdev_findbyaddr.c |
| * |
| * SPDX-License-Identifier: Apache-2.0 |
| * |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. The |
| * ASF licenses this file to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance with the |
| * License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the |
| * License for the specific language governing permissions and limitations |
| * under the License. |
| * |
| ****************************************************************************/ |
| |
| /**************************************************************************** |
| * Included Files |
| ****************************************************************************/ |
| |
| #include <nuttx/config.h> |
| |
| #include <stdbool.h> |
| #include <stdint.h> |
| #include <string.h> |
| #include <errno.h> |
| #include <debug.h> |
| |
| #include <netinet/in.h> |
| |
| #include <nuttx/net/netdev.h> |
| #include <nuttx/net/ip.h> |
| |
| #include "arp/arp.h" |
| #include "neighbor/neighbor.h" |
| #include "utils/utils.h" |
| #include "devif/devif.h" |
| #include "inet/inet.h" |
| #include "route/route.h" |
| #include "netdev/netdev.h" |
| |
| /**************************************************************************** |
| * Private Functions |
| ****************************************************************************/ |
| |
| /**************************************************************************** |
| * Name: netdev_prefixlen_findby_lipv4addr |
| * |
| * 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). |
| * |
| * Input Parameters: |
| * lipaddr - Local, IPv4 address assigned to the network device. Or any |
| * IPv4 address on the sub-net served by the network device. |
| * prefixlen - The length of matching prefix. Range: -1(no match) ~ 32 |
| * |
| * Returned Value: |
| * Pointer to driver on success; null on failure |
| * |
| ****************************************************************************/ |
| |
| #ifdef CONFIG_NET_IPv4 |
| static FAR struct net_driver_s * |
| netdev_prefixlen_findby_lipv4addr(in_addr_t lipaddr, FAR int8_t *prefixlen) |
| { |
| FAR struct net_driver_s *dev; |
| FAR struct net_driver_s *bestdev = NULL; |
| int8_t bestpref = -1; |
| #ifdef CONFIG_ROUTE_LONGEST_MATCH |
| int8_t len; |
| #endif |
| |
| /* Examine each registered network device */ |
| |
| net_lock(); |
| for (dev = g_netdevices; dev; dev = dev->flink) |
| { |
| /* Is the interface in the "up" state? */ |
| |
| if ((dev->d_flags & IFF_UP) != 0 && |
| !net_ipv4addr_cmp(dev->d_ipaddr, INADDR_ANY)) |
| { |
| #ifndef CONFIG_ROUTE_LONGEST_MATCH |
| /* Yes.. check for an address match (under the netmask) */ |
| |
| if (net_ipv4addr_maskcmp(dev->d_ipaddr, lipaddr, |
| dev->d_netmask)) |
| { |
| /* Its a match */ |
| |
| bestdev = dev; |
| bestpref = 32; /* Regard as best (exact) match */ |
| break; |
| } |
| #else |
| /* Longest prefix flow: First, check for an exact address match */ |
| |
| if (net_ipv4addr_cmp(dev->d_ipaddr, lipaddr)) |
| { |
| /* It's an exact match */ |
| |
| bestdev = dev; |
| bestpref = 32; |
| break; |
| } |
| |
| /* Then, check for an address match (under the netmask) */ |
| |
| if (net_ipv4addr_maskcmp(dev->d_ipaddr, lipaddr, |
| dev->d_netmask)) |
| { |
| len = (int8_t)net_ipv4_mask2pref(dev->d_netmask); |
| |
| /* Regard current device as better if: |
| * 1. It has longer prefix length |
| * 2. It has the same prefix length but it has target address |
| * in the ARP cache (We don't have other information |
| * for the precedence of networks) |
| */ |
| |
| if (len > bestpref |
| #ifdef CONFIG_NET_ARP |
| || (len == bestpref |
| && arp_find(lipaddr, NULL, dev, true) == OK) |
| #endif |
| ) |
| { |
| bestdev = dev; |
| bestpref = len; |
| } |
| } |
| #endif /* CONFIG_ROUTE_LONGEST_MATCH */ |
| } |
| } |
| |
| net_unlock(); |
| *prefixlen = bestpref; |
| return bestdev; |
| } |
| #endif /* CONFIG_NET_IPv4 */ |
| |
| /**************************************************************************** |
| * Name: netdev_prefixlen_findby_lipv6addr |
| * |
| * 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). |
| * |
| * Input Parameters: |
| * lipaddr - Local, IPv6 address assigned to the network device. Or any |
| * IPv6 address on the sub-net served by the network device. |
| * prefixlen - The length of matching prefix. Range: -1(no match) ~ 128 |
| * |
| * Returned Value: |
| * Pointer to driver on success; null on failure |
| * |
| ****************************************************************************/ |
| |
| #ifdef CONFIG_NET_IPv6 |
| static FAR struct net_driver_s * |
| netdev_prefixlen_findby_lipv6addr(const net_ipv6addr_t lipaddr, |
| FAR int16_t *prefixlen) |
| { |
| FAR struct net_driver_s *dev; |
| FAR struct net_driver_s *bestdev = NULL; |
| int16_t bestpref = -1; |
| #ifdef CONFIG_ROUTE_LONGEST_MATCH |
| FAR struct netdev_ifaddr6_s *ifaddr6; |
| FAR struct neighbor_entry_s *ne; |
| FAR struct net_driver_s *hint; |
| int16_t len; |
| #endif |
| |
| net_lock(); |
| |
| #ifdef CONFIG_ROUTE_LONGEST_MATCH |
| /* Find a hint from neighbor table in case same prefix length exists on |
| * multiple devices. |
| */ |
| |
| ne = neighbor_findentry(lipaddr); |
| hint = ne ? ne->ne_dev : NULL; |
| #endif |
| |
| /* Examine each registered network device */ |
| |
| for (dev = g_netdevices; dev; dev = dev->flink) |
| { |
| /* Is the interface in the "up" state? */ |
| |
| if ((dev->d_flags & IFF_UP) != 0 && NETDEV_HAS_V6ADDR(dev)) |
| { |
| #ifndef CONFIG_ROUTE_LONGEST_MATCH |
| /* Yes.. check for an address match (under the netmask) */ |
| |
| if (NETDEV_V6ADDR_ONLINK(dev, lipaddr)) |
| { |
| /* Its a match */ |
| |
| bestdev = dev; |
| bestpref = 128; /* Regard as best (exact) match */ |
| break; |
| } |
| #else |
| /* Longest prefix flow: First, check for an exact address match */ |
| |
| if (NETDEV_IS_MY_V6ADDR(dev, lipaddr)) |
| { |
| /* It's an exact match */ |
| |
| bestdev = dev; |
| bestpref = 128; |
| break; |
| } |
| |
| /* Then, check for an address match (under the netmask) */ |
| |
| if ((ifaddr6 = netdev_ipv6_lookup(dev, lipaddr, true)) != NULL) |
| { |
| len = (int16_t)net_ipv6_mask2pref(ifaddr6->mask); |
| |
| /* Regard current device as better if: |
| * 1. It has longer prefix length |
| * 2. It has the same prefix length but it has target address |
| * in the neighbor cache (We don't have other information |
| * for the precedence of networks) |
| */ |
| |
| if (len > bestpref || (len == bestpref && hint == dev)) |
| { |
| bestdev = dev; |
| bestpref = len; |
| } |
| } |
| #endif /* CONFIG_ROUTE_LONGEST_MATCH */ |
| } |
| } |
| |
| net_unlock(); |
| *prefixlen = bestpref; |
| return bestdev; |
| } |
| #endif /* CONFIG_NET_IPv6 */ |
| |
| /**************************************************************************** |
| * Public Functions |
| ****************************************************************************/ |
| |
| /**************************************************************************** |
| * Name: netdev_findby_lipv4addr |
| * |
| * 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). |
| * |
| * Input Parameters: |
| * lipaddr - Local, IPv4 address assigned to the network device. Or any |
| * IPv4 address on the sub-net served by the network device. |
| * |
| * Returned Value: |
| * Pointer to driver on success; null on failure |
| * |
| ****************************************************************************/ |
| |
| #ifdef CONFIG_NET_IPv4 |
| FAR struct net_driver_s *netdev_findby_lipv4addr(in_addr_t lipaddr) |
| { |
| int8_t prefixlen; |
| return netdev_prefixlen_findby_lipv4addr(lipaddr, &prefixlen); |
| } |
| #endif /* CONFIG_NET_IPv4 */ |
| |
| /**************************************************************************** |
| * Name: netdev_findby_lipv6addr |
| * |
| * 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). |
| * |
| * Input Parameters: |
| * lipaddr - Local, IPv6 address assigned to the network device. Or any |
| * IPv6 address on the sub-net served by the network device. |
| * |
| * Returned Value: |
| * Pointer to driver on success; null on failure |
| * |
| ****************************************************************************/ |
| |
| #ifdef CONFIG_NET_IPv6 |
| FAR struct net_driver_s *netdev_findby_lipv6addr( |
| const net_ipv6addr_t lipaddr) |
| { |
| int16_t prefixlen; |
| return netdev_prefixlen_findby_lipv6addr(lipaddr, &prefixlen); |
| } |
| #endif /* CONFIG_NET_IPv6 */ |
| |
| /**************************************************************************** |
| * Name: netdev_findby_ripv4addr |
| * |
| * Description: |
| * Find a previously registered network device by matching the remote |
| * IPv4 address that can be reached by the device. |
| * |
| * Input Parameters: |
| * lipaddr - Local, bound address of a connection (used only if ripaddr is |
| * the broadcast address). |
| * ripaddr - Remote address of a connection to use in the lookup |
| * |
| * Returned Value: |
| * Pointer to driver on success; null on failure |
| * |
| ****************************************************************************/ |
| |
| #ifdef CONFIG_NET_IPv4 |
| FAR struct net_driver_s *netdev_findby_ripv4addr(in_addr_t lipaddr, |
| in_addr_t ripaddr) |
| { |
| FAR struct net_driver_s *dev; |
| int8_t prefixlen; |
| #ifdef CONFIG_NET_ROUTE |
| in_addr_t router; |
| int ret; |
| #endif |
| |
| /* First, check if this is the broadcast IP address */ |
| |
| if (net_ipv4addr_cmp(ripaddr, INADDR_BROADCAST)) |
| { |
| /* Yes.. Check the local, bound address. Is it INADDR_ANY? */ |
| |
| if (net_ipv4addr_cmp(lipaddr, INADDR_ANY)) |
| { |
| /* Yes.. In this case, I think we are supposed to send the |
| * broadcast packet out ALL locally available networks. I am not |
| * sure of that and, in any event, there is nothing we can do |
| * about that here. |
| */ |
| |
| return netdev_default(); |
| } |
| else |
| { |
| /* Return the device associated with the local address */ |
| |
| return netdev_findby_lipv4addr(lipaddr); |
| } |
| } |
| |
| /* Check if the address maps to a locally available network |
| * Note: If longest prefix match is not enabled, prefixlen will be 32 if |
| * matched and it will disable further routing lookup. |
| */ |
| |
| dev = netdev_prefixlen_findby_lipv4addr(ripaddr, &prefixlen); |
| |
| #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 |
| * with longer prefix. |
| */ |
| |
| ret = net_ipv4_router(ripaddr, &router, prefixlen); |
| if (ret >= 0) |
| { |
| /* Success... try to find the network device associated with the local |
| * router address |
| */ |
| |
| dev = netdev_findby_lipv4addr(router); |
| } |
| #endif /* CONFIG_NET_ROUTE */ |
| |
| /* Return the device we found. */ |
| |
| if (dev) |
| { |
| return dev; |
| } |
| |
| /* 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. Let's |
| * try the default network device. |
| */ |
| |
| return netdev_default(); |
| } |
| #endif /* CONFIG_NET_IPv4 */ |
| |
| /**************************************************************************** |
| * Name: netdev_findby_ripv6addr |
| * |
| * Description: |
| * Find a previously registered network device by matching the remote |
| * IPv6 address that can be reached by the device. |
| * |
| * Input Parameters: |
| * lipaddr - Local, bound address of a connection (used only if ripaddr is |
| * a multicast address). |
| * ripaddr - Remote address of a connection to use in the lookup |
| * |
| * Returned Value: |
| * Pointer to driver on success; null on failure |
| * |
| ****************************************************************************/ |
| |
| #ifdef CONFIG_NET_IPv6 |
| FAR struct net_driver_s *netdev_findby_ripv6addr( |
| const net_ipv6addr_t lipaddr, |
| const net_ipv6addr_t ripaddr) |
| { |
| FAR struct net_driver_s *dev; |
| int16_t prefixlen; |
| #ifdef CONFIG_NET_ROUTE |
| net_ipv6addr_t router; |
| int ret; |
| #endif |
| |
| /* First, check if this is the multicast IP address */ |
| |
| if (net_is_addr_mcast(ripaddr)) |
| { |
| /* Yes.. Check the local, bound address. Is it the IPv6 unspecified |
| * address? |
| */ |
| |
| if (net_ipv6addr_cmp(lipaddr, g_ipv6_unspecaddr)) |
| { |
| /* Yes.. In this case, I think we are supposed to send the |
| * broadcast packet out ALL locally available networks. I am not |
| * sure of that and, in any event, there is nothing we can do |
| * about that here. |
| */ |
| |
| return netdev_default(); |
| } |
| else |
| { |
| /* Return the device associated with the local address */ |
| |
| return netdev_findby_lipv6addr(lipaddr); |
| } |
| } |
| |
| /* Check if the address maps to a locally available network |
| * Note: If longest prefix match is not enabled, prefixlen will be 128 if |
| * matched and it will disable further routing lookup. |
| */ |
| |
| dev = netdev_prefixlen_findby_lipv6addr(ripaddr, &prefixlen); |
| |
| #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 |
| * with longer prefix. |
| */ |
| |
| ret = net_ipv6_router(ripaddr, router, prefixlen); |
| if (ret >= 0) |
| { |
| /* Success... try to find the network device associated with the local |
| * router address |
| */ |
| |
| dev = netdev_findby_lipv6addr(router); |
| } |
| #endif /* CONFIG_NET_ROUTE */ |
| |
| /* Return the device we found. */ |
| |
| if (dev) |
| { |
| return dev; |
| } |
| |
| /* 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. Let's |
| * try the default network device. |
| */ |
| |
| return netdev_default(); |
| } |
| #endif /* CONFIG_NET_IPv6 */ |
