/**************************************************************************** * net/neighbor/neighbor_out.c * * Copyright (C) 2018 Pinecone Inc. All rights reserved. * Author: Xiang Xiao * * 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 #include #include #include "neighbor/neighbor.h" /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: neighbor_out * * Description: * This function should be called before sending out an IPv6 packet. The * function checks the destination IPv6 address of the IPv6 packet to see * what L2 address that should be used as a destination L2 address. * * If the destination IPv6 address is in the local network (determined * by logical ANDing of netmask and our IPv6 address), the function * checks the Neighbor Table to see if an entry for the destination IPv6 * address is found. If so, an L2 header is pre-pended at the beginning * of the packet and the function returns. * * If no Neighbor Table entry is found for the destination IPv6 address, * the packet in the d_buf is replaced by an ICMPv6 Neighbor Solicit * request packet for the IPv6 address. The IPv6 packet is dropped and * it is assumed that the higher level protocols (e.g., TCP) eventually * will retransmit the dropped packet. * * Upon return in either the case, a packet to be sent is present in the * d_buf buffer and the d_len field holds the length of the L2 frame that * should be transmitted. * ****************************************************************************/ void neighbor_out(FAR struct net_driver_s *dev) { switch (dev->d_lltype) { #ifdef CONFIG_NET_ETHERNET case NET_LL_ETHERNET: neighbor_ethernet_out(dev); break; #endif default: break; } }