/****************************************************************************
* net/icmpv6/icmpv6_input.c
* Handling incoming ICMPv6 input
*
* 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 <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 <nuttx/net/dns.h>
#include "devif/devif.h"
#include "neighbor/neighbor.h"
#include "utils/utils.h"
#include "icmpv6/icmpv6.h"
#include "mld/mld.h"
#ifdef CONFIG_NET_ICMPv6
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#define ICMPv6REPLY ((FAR struct icmpv6_echo_reply_s *)icmpv6)
#define ICMPv6SIZE ((dev)->d_len - iplen)
#define ICMPv6SOLICIT ((FAR struct icmpv6_neighbor_solicit_s *)icmpv6)
#define ICMPv6ADVERTISE ((FAR struct icmpv6_neighbor_advertise_s *)icmpv6)
#define ICMPv6RADVERTISE ((FAR struct icmpv6_router_advertise_s *)icmpv6)
#define MLDQUERY ((FAR struct mld_mcast_listen_query_s *)icmpv6)
#define MLDREPORT_V1 ((FAR struct mld_mcast_listen_report_v1_s *)icmpv6)
#define MLDREPORT_V2 ((FAR struct mld_mcast_listen_report_v2_s *)icmpv6)
#define MLDDONE ((FAR struct mld_mcast_listen_done_s *)icmpv6)
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: icmpv6_datahandler
*
* Description:
* Handle ICMPv6 echo replies that are not accepted by the application.
*
* Input Parameters:
* dev - Device instance only the input packet in d_buf, length = d_len;
* conn - A pointer to the ICMPv6 connection structure
* buffer - A pointer to the buffer to be copied to the read-ahead
* buffers
* buflen - The number of bytes to copy to the read-ahead buffer.
*
* Returned Value:
* The number of bytes actually buffered is returned. This will be either
* zero or equal to buflen; partial packets are not buffered.
*
****************************************************************************/
#ifdef CONFIG_NET_ICMPv6_SOCKET
static uint16_t icmpv6_datahandler(FAR struct net_driver_s *dev,
FAR struct icmpv6_conn_s *conn,
unsigned int iplen)
{
FAR struct ipv6_hdr_s *ipv6;
struct sockaddr_in6 inaddr;
FAR struct iob_s *iob;
uint16_t buflen;
int ret;
/* Put the IPv6 address at the beginning of the read-ahead buffer */
iob = dev->d_iob;
ipv6 = IPv6BUF;
inaddr.sin6_family = AF_INET6;
inaddr.sin6_port = 0;
net_ipv6addr_copy(inaddr.sin6_addr.s6_addr16, ipv6->srcipaddr);
/* Copy the src address info into the front of I/O buffer chain which
* overwrites the contents of the packet header field.
*/
memcpy(iob->io_data, &inaddr, sizeof(struct sockaddr_in6));
/* Copy the new ICMPv6 reply into the I/O buffer chain (without waiting) */
buflen = ICMPv6SIZE;
/* Trim l3 header */
iob = iob_trimhead(iob, iplen);
/* Add the new I/O buffer chain to the tail of the read-ahead queue (again
* without waiting).
*/
ret = iob_tryadd_queue(iob, &conn->readahead);
if (ret < 0)
{
nerr("ERROR: Failed to queue the I/O buffer chain: %d\n", ret);
iob_free_chain(iob);
}
else
{
ninfo("Buffered %d bytes\n", buflen);
}
/* Device buffer must be enqueue or freed, clear the handle */
netdev_iob_clear(dev);
return buflen;
}
#endif
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: icmpv6_input
*
* Description:
* Handle incoming ICMPv6 input
*
* Input Parameters:
* dev - The device driver structure containing the received ICMPv6
* packet
* iplen - The size of the IPv6 header. This may be larger than
* IPv6_HDRLEN the IPv6 header if IPv6 extension headers are
* present.
*
* Returned Value:
* None
*
* Assumptions:
* The network is locked.
*
****************************************************************************/
void icmpv6_input(FAR struct net_driver_s *dev, unsigned int iplen)
{
FAR struct ipv6_hdr_s *ipv6 = IPv6BUF;
FAR struct icmpv6_hdr_s *icmpv6 = IPBUF(iplen);
#ifdef CONFIG_NET_STATISTICS
g_netstats.icmpv6.recv++;
#endif
/* REVISIT:
* - Verify that the message length is valid.
* - Verify the ICMPv6 checksum
*/
/* Handle the ICMPv6 message by its type */
switch (icmpv6->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))
{
if (sol->opttype == ICMPv6_OPT_SRCLLADDR)
{
/* Save the sender's address mapping in our Neighbor Table. */
neighbor_add(dev, ipv6->srcipaddr, sol->srclladdr);
}
/* Yes.. Send a neighbor advertisement back to where the neighbor
* solicitation came from.
*/
icmpv6_advertise(dev, ipv6->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(ipv6->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(dev, ipv6->srcipaddr, adv->tgtlladdr);
}
#ifdef CONFIG_NET_ICMPv6_NEIGHBOR
/* Then notify any logic waiting for the Neighbor Advertisement */
icmpv6_notify(ipv6->srcipaddr);
#endif
/* We consumed the packet but we don't send anything in
* response.
*/
goto icmpv6_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;
FAR uint8_t *options;
bool prefix = false;
uint16_t pktlen;
uint16_t optlen;
int ndx;
/* Get the length of the option data */
pktlen = (uint16_t)ipv6->len[0] << 8 | ipv6->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. Options immediately follow
* the ICMPv6 router advertisement.
*/
adv = ICMPv6RADVERTISE;
options = (FAR uint8_t *)adv +
sizeof(struct icmpv6_router_advertise_s);
for (ndx = 0; ndx < optlen; )
{
FAR struct icmpv6_generic_s *opt =
(FAR struct icmpv6_generic_s *)&options[ndx];
switch (opt->opttype)
{
case ICMPv6_OPT_SRCLLADDR:
{
FAR struct icmpv6_srclladdr_s *sllopt =
(FAR struct icmpv6_srclladdr_s *)opt;
neighbor_add(dev, ipv6->srcipaddr, sllopt->srclladdr);
}
break;
case ICMPv6_OPT_PREFIX:
{
FAR struct icmpv6_prefixinfo_s *prefixopt =
(FAR struct icmpv6_prefixinfo_s *)opt;
/* Is the "A" flag set? */
if ((prefixopt->flags & ICMPv6_PRFX_FLAG_A) != 0)
{
/* Yes.. Set the new network addresses. */
icmpv6_setaddresses(dev, ipv6->srcipaddr,
prefixopt->prefix, prefixopt->preflen);
/* Notify any waiting threads */
icmpv6_rnotify(dev);
prefix = true;
}
}
break;
case ICMPv6_OPT_MTU:
{
FAR struct icmpv6_mtu_s *mtuopt =
(FAR struct icmpv6_mtu_s *)opt;
dev->d_pktsize = NTOHS(mtuopt->mtu[1]) + dev->d_llhdrlen;
}
break;
#ifdef CONFIG_ICMPv6_AUTOCONF_RDNSS
case ICMPv6_OPT_RDNSS:
{
FAR struct icmpv6_rdnss_s *rdnss =
(FAR struct icmpv6_rdnss_s *)opt;
FAR struct in6_addr *servers;
struct sockaddr_in6 addr;
int nservers;
int ret;
int i;
if (rdnss->optlen < 3)
{
nerr("rdnss error length %d\n", rdnss->optlen);
break;
}
/* optlen is in units of 8 bytes. The header is 1 unit
* (8 bytes) and each address is another 2 units
* (16 bytes). So the number of addresses is equal to
* (optlen - 1) / 2.
*/
servers = (FAR struct in6_addr *)rdnss->servers;
nservers = (rdnss->optlen - 1) / 2;
/* Set the IPv6 DNS server address */
memset(&addr, 0, sizeof(addr));
addr.sin6_family = AF_INET6;
for (i = 0; i < CONFIG_NETDB_DNSSERVER_NAMESERVERS &&
i < nservers; i++)
{
net_ipv6addr_copy(&addr.sin6_addr, servers + i);
ret = dns_add_nameserver(
(FAR const struct sockaddr *)&addr,
sizeof(struct sockaddr_in6));
if (ret < 0 && ret != -EEXIST)
{
nerr("dns add nameserver failed %d", ret);
}
}
}
break;
#endif
default:
break;
}
/* Skip to the next option (units of octets) */
ndx += (opt->optlen << 3);
}
if (prefix)
{
goto icmpv6_send_nothing;
}
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.
*/
icmpv6->type = ICMPv6_ECHO_REPLY;
net_ipv6addr_copy(ipv6->destipaddr, ipv6->srcipaddr);
net_ipv6addr_copy(ipv6->srcipaddr, dev->d_ipv6addr);
icmpv6->chksum = 0;
icmpv6->chksum = ~icmpv6_chksum(dev, iplen);
}
break;
#ifdef CONFIG_NET_ICMPv6_SOCKET
/* If an ICMPv6 echo reply is received then there should also be
* a thread waiting to received the echo response.
*/
case ICMPv6_ECHO_REPLY:
{
FAR struct icmpv6_echo_reply_s *reply;
FAR struct icmpv6_conn_s *conn;
uint16_t flags = ICMPv6_NEWDATA;
/* Nothing consumed the ICMP reply. That might be because this is
* an old, invalid reply or simply because the ping application
* has not yet put its poll or recv in place.
*/
/* Is there any connection that might expect this reply? */
reply = ICMPv6REPLY;
conn = icmpv6_findconn(dev, reply->id);
if (conn == NULL)
{
/* No.. drop the packet */
goto icmpv6_drop_packet;
}
/* Dispatch the ECHO reply to the waiting thread */
flags = devif_conn_event(dev, flags, conn->sconn.list);
/* Was the ECHO reply consumed by any waiting thread? */
if ((flags & ICMPv6_NEWDATA) != 0)
{
uint16_t nbuffered;
/* Yes.. Add the ICMP echo reply to the IPPROTO_ICMP socket read
* ahead buffer.
*/
nbuffered = icmpv6_datahandler(dev, conn, iplen);
if (nbuffered == 0)
{
/* Could not buffer the data.. drop the packet */
goto icmpv6_drop_packet;
}
}
goto icmpv6_send_nothing;
}
break;
#endif
#ifdef CONFIG_NET_MLD
/* Dispatch received Multicast Listener Discovery (MLD) packets. */
case ICMPV6_MCAST_LISTEN_QUERY: /* Multicast Listener Query, RFC 2710 and RFC 3810 */
{
FAR struct mld_mcast_listen_query_s *query = MLDQUERY;
int ret;
ret = mld_query(dev, query);
if (ret < 0)
{
goto icmpv6_drop_packet;
}
}
break;
case ICMPV6_MCAST_LISTEN_REPORT_V1: /* Version 1 Multicast Listener Report, RFC 2710 */
{
FAR struct mld_mcast_listen_report_v1_s *report = MLDREPORT_V1;
int ret;
ret = mld_report_v1(dev, report);
if (ret < 0)
{
goto icmpv6_drop_packet;
}
}
break;
case ICMPV6_MCAST_LISTEN_REPORT_V2: /* Version 2 Multicast Listener Report, RFC 3810 */
{
FAR struct mld_mcast_listen_report_v2_s *report = MLDREPORT_V2;
int ret;
ret = mld_report_v2(dev, report);
if (ret < 0)
{
goto icmpv6_drop_packet;
}
}
break;
case ICMPV6_MCAST_LISTEN_DONE: /* Multicast Listener Done, RFC 2710 */
{
FAR struct mld_mcast_listen_done_s *done = MLDDONE;
int ret;
ret = mld_done(dev, done);
if (ret < 0)
{
goto icmpv6_drop_packet;
}
}
break;
#endif
default:
{
nwarn("WARNING: Unknown ICMPv6 type: %d\n", icmpv6->type);
goto icmpv6_type_error;
}
}
#ifdef CONFIG_NET_STATISTICS
if (dev->d_len > 0)
{
ninfo("Outgoing ICMPv6 packet length: %d (%d)\n",
dev->d_len, (ipv6->len[0] << 8) | ipv6->len[1]);
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
icmpv6_send_nothing:
dev->d_len = 0;
}
#endif /* CONFIG_NET_ICMPv6 */