/****************************************************************************
* net/icmpv6/icmpv6_input.c
* Handling incoming ICMPv6 input
*
* Copyright (C) 2015 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Adapted for NuttX from logic in uIP which also has a BSD-like license:
*
* Original author Adam Dunkels <adam@dunkels.com>
* 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 <nuttx/config.h>
#include <stdint.h>
#include <string.h>
#include <debug.h>
#include <nuttx/net/netconfig.h>
#include <nuttx/net/netdev.h>
#include <nuttx/net/netstats.h>
#include <nuttx/net/icmpv6.h>
#include "devif/devif.h"
#include "neighbor/neighbor.h"
#include "utils/utils.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;
/* 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.
*/
icmpv6_advertise(dev, icmp->srcipaddr);
/* All statistics have been updated. Nothing to do but exit. */
return;
}
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_ROUTER
/* Check if we received a Router Solicitation */
case ICMPV6_ROUTER_SOLICIT:
{
/* Just give a knee-jerk Router Advertisement in respond with no
* further examination of the Router Solicitation.
*/
icmpv6_radvertise(dev);
/* All statistics have been updated. Nothing to do but exit. */
return;
}
#endif
#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, icmp->srcipaddr, 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 type: %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 */