/**************************************************************************** * net/icmpv6/icmpv6_input.c * Handling incoming ICMPv6 input * * Copyright (C) 2015 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * Adapted for NuttX from logic in uIP which also has a BSD-like license: * * Original author Adam Dunkels * Copyright () 2001-2003, Adam Dunkels. * All rights reserved. * * 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. The name of the author may not be used to endorse or promote * products derived from this software without specific prior * written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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 #ifdef CONFIG_NET #include #include #include #include #include #include #include #include #include #include "devif/devif.h" #include "utils/utils.h" #include "neighbor/neighbor.h" #include "icmpv6/icmpv6.h" #ifdef CONFIG_NET_ICMPv6 /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ #define ETHBUF ((struct eth_hdr_s *)&dev->d_buf[0]) #define ICMPv6BUF ((struct icmpv6_iphdr_s *)&dev->d_buf[NET_LL_HDRLEN(dev)]) #define ICMPv6SOLICIT \ ((struct icmpv6_neighbor_solicit_s *)&dev->d_buf[NET_LL_HDRLEN(dev) + IPv6_HDRLEN]) #define ICMPv6ADVERTISE \ ((struct icmpv6_neighbor_advertise_s *)&dev->d_buf[NET_LL_HDRLEN(dev) + IPv6_HDRLEN]) #define ICMPv6RADVERTISE \ ((struct icmpv6_router_advertise_s *)&dev->d_buf[NET_LL_HDRLEN(dev) + IPv6_HDRLEN]) /**************************************************************************** * Public Data ****************************************************************************/ #if defined(CONFIG_NET_ICMPv6_PING) || defined(CONFIG_NET_ICMPv6_NEIGHBOR) /* This is the singleton "connection" structure for TX polls and echo replies */ struct icmpv6_conn_s g_icmpv6_conn; #endif /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: icmpv6_input * * Description: * Handle incoming ICMPv6 input * * Parameters: * dev - The device driver structure containing the received ICMPv6 * packet * * Return: * None * * Assumptions: * Called from the interrupt level or with interrupts disabled. * ****************************************************************************/ void icmpv6_input(FAR struct net_driver_s *dev) { FAR struct icmpv6_iphdr_s *icmp = ICMPv6BUF; #ifdef CONFIG_NET_STATISTICS g_netstats.icmpv6.recv++; #endif /* Handle the ICMPv6 message by its type */ switch (icmp->type) { /* If we get a neighbor solicitation for our address we should send * a neighbor advertisement message back. */ case ICMPv6_NEIGHBOR_SOLICIT: { FAR struct icmpv6_neighbor_solicit_s *sol; FAR struct icmpv6_neighbor_advertise_s *adv; /* Check if we are the target of the solicitation */ sol = ICMPv6SOLICIT; if (net_ipv6addr_cmp(sol->tgtaddr, dev->d_ipv6addr)) { /* Yes.. Send a neighbor advertisement back to where the neighbor * solicitation came from. * * Set up the IPv6 header. Most is probably already in place from * the Neighbor Solicitation. We could save some time here. */ icmp->vtc = 0x60; /* Version/traffic class (MS) */ icmp->tcf = 0; /* Traffic class (LS)/Flow label (MS) */ icmp->flow = 0; /* Flow label (LS) */ /* Length excludes the IPv6 header */ icmp->len[0] = (sizeof(struct icmpv6_neighbor_advertise_s) >> 8); icmp->len[1] = (sizeof(struct icmpv6_neighbor_advertise_s) & 0xff); icmp->proto = IP_PROTO_ICMP6; /* Next header */ icmp->ttl = 255; /* Hop limit */ /* Swap source for destination IP address, add our source IP * address */ net_ipv6addr_copy(icmp->destipaddr, icmp->srcipaddr); net_ipv6addr_copy(icmp->srcipaddr, dev->d_ipv6addr); /* Set up the ICMPv6 Neighbor Advertise response */ adv = ICMPv6ADVERTISE; adv->type = ICMPv6_NEIGHBOR_ADVERTISE; /* Message type */ adv->code = 0; /* Message qualifier */ adv->flags[0] = ICMPv6_NADV_FLAG_S | ICMPv6_NADV_FLAG_O; /* Solicited+Override flags. */ adv->flags[1] = 0; adv->flags[2] = 0; adv->flags[3] = 0; /* Copy the target address into the Neighbor Advertisement message */ net_ipv6addr_copy(adv->tgtaddr, dev->d_ipv6addr); /* Set up the options */ adv->opttype = ICMPv6_OPT_TGTLLADDR; /* Option type */ adv->optlen = 1; /* Option length = 1 octet */ /* Copy our link layer address into the message * REVISIT: What if the link layer is not Ethernet? */ memcpy(adv->tgtlladdr, &dev->d_mac, IFHWADDRLEN); /* Calculate the checksum over both the ICMP header and payload */ icmp->chksum = 0; icmp->chksum = ~icmpv6_chksum(dev); /* Set the size to the size of the IPv6 header and the payload size */ dev->d_len = IPv6_HDRLEN + sizeof(struct icmpv6_neighbor_advertise_s); #ifdef CONFIG_NET_ETHERNET /* Add the size of the Ethernet header */ dev->d_len += ETH_HDRLEN; /* Move the source and to the destination addresses in the * Ethernet header and use our MAC as the new source address. */ #ifdef CONFIG_NET_MULTILINK if (dev->d_lltype == NET_LL_ETHERNET) #endif { FAR struct eth_hdr_s *eth = ETHBUF; memcpy(eth->dest, eth->src, ETHER_ADDR_LEN); memcpy(eth->src, dev->d_mac.ether_addr_octet, ETHER_ADDR_LEN); /* Set the IPv6 Ethernet type */ eth->type = HTONS(ETHTYPE_IP6); } #endif /* No additional neighbor lookup is required on this packet * (We are using a multicast address). */ IFF_SET_NOARP(dev->d_flags); } else { goto icmpv6_drop_packet; } } break; /* Check if we received a Neighbor Advertisement */ case ICMPv6_NEIGHBOR_ADVERTISE: { FAR struct icmpv6_neighbor_advertise_s *adv; /* If the IPv6 destination address matches our address, and if so, * add the neighbor address mapping to the list of neighbors. * * Missing checks: * optlen = 1 (8 octets) * Should only update Neighbor Table if [O]verride bit is set in flags */ adv = ICMPv6ADVERTISE; if (net_ipv6addr_cmp(icmp->destipaddr, dev->d_ipv6addr)) { /* This message is required to support the Target link-layer * address option. */ if (adv->opttype == ICMPv6_OPT_TGTLLADDR) { /* Save the sender's address mapping in our Neighbor Table. */ neighbor_add(icmp->srcipaddr, (FAR struct neighbor_addr_s *)adv->tgtlladdr); #ifdef CONFIG_NET_ICMPv6_NEIGHBOR /* Then notify any logic waiting for the Neighbor Advertisement */ icmpv6_notify(icmp->srcipaddr); #endif /* We consumed the packet but we don't send anything in * response. */ goto icmpv_send_nothing; } } goto icmpv6_drop_packet; } break; #ifdef CONFIG_NET_ICMPv6_AUTOCONF /* Check if we received a Router Advertisement */ case ICMPV6_ROUTER_ADVERTISE: { FAR struct icmpv6_router_advertise_s *adv; uint16_t pktlen; uint16_t optlen; int ndx; /* Get the length of the option data */ pktlen = (uint16_t)icmp->len[0] << 8 | icmp->len[1]; if (pktlen <= ICMPv6_RADV_MINLEN) { /* Too small to contain any options */ goto icmpv6_drop_packet; } optlen = ICMPv6_RADV_OPTLEN(pktlen); /* We need to have a valid router advertisement with a Prefix and * with the "A" bit set in the flags. */ adv = ICMPv6RADVERTISE; for (ndx = 0; ndx + sizeof(struct icmpv6_prefixinfo_s) < optlen; ) { FAR struct icmpv6_prefixinfo_s *opt = (FAR struct icmpv6_prefixinfo_s *)&adv->options[ndx]; /* Is this the sought for prefix? Is it the correct size? Is * the "A" flag set? */ if (opt->opttype && opt->optlen == 4 && (opt->flags & ICMPv6_PRFX_FLAG_A) != 0) { /* Yes.. Notify any waiting threads */ icmpv6_rnotify(dev, opt->prefix, opt->preflen); goto icmpv_send_nothing; } /* Skip to the next option (units of octets) */ ndx += (opt->optlen << 3); } goto icmpv6_drop_packet; } break; #endif /* Handle the ICMPv6 Echo Request */ case ICMPv6_ECHO_REQUEST: { /* ICMPv6 echo (i.e., ping) processing. This is simple, we only * change the ICMPv6 type from ECHO to ECHO_REPLY and update the * ICMPv6 checksum before we return the packet. */ icmp->type = ICMPv6_ECHO_REPLY; net_ipv6addr_copy(icmp->destipaddr, icmp->srcipaddr); net_ipv6addr_copy(icmp->srcipaddr, dev->d_ipv6addr); icmp->chksum = 0; icmp->chksum = ~icmpv6_chksum(dev); } break; #ifdef CONFIG_NET_ICMPv6_PING /* If an ICMPv6 echo reply is received then there should also be * a thread waiting to received the echo response. */ case ICMPv6_ECHO_REPLY: { uint16_t flags = ICMPv6_ECHOREPLY; /* Dispatch the ECHO reply to the waiting thread */ flags = devif_callback_execute(dev, icmp, flags, g_icmpv6_conn.list); /* If the ECHO reply was not handled, then drop the packet */ if (flags == ICMPv6_ECHOREPLY) { /* The ECHO reply was not handled */ goto icmpv6_drop_packet; } } break; #endif default: { nlldbg("Unknown ICMPv6 cmd: %d\n", icmp->type); goto icmpv6_type_error; } } nllvdbg("Outgoing ICMPv6 packet length: %d (%d)\n", dev->d_len, (icmp->len[0] << 8) | icmp->len[1]); #ifdef CONFIG_NET_STATISTICS g_netstats.icmpv6.sent++; g_netstats.ipv6.sent++; #endif return; icmpv6_type_error: #ifdef CONFIG_NET_STATISTICS g_netstats.icmpv6.typeerr++; #endif icmpv6_drop_packet: #ifdef CONFIG_NET_STATISTICS g_netstats.icmpv6.drop++; #endif icmpv_send_nothing: dev->d_len = 0; } #endif /* CONFIG_NET_ICMPv6 */ #endif /* CONFIG_NET */