350 lines
11 KiB
C
350 lines
11 KiB
C
/****************************************************************************
|
|
* net/icmpv6/icmpv6_neighbor.c
|
|
*
|
|
* 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 <unistd.h>
|
|
#include <string.h>
|
|
#include <debug.h>
|
|
|
|
#include <netinet/in.h>
|
|
#include <net/if.h>
|
|
|
|
#include <nuttx/semaphore.h>
|
|
#include <nuttx/net/net.h>
|
|
#include <nuttx/net/netdev.h>
|
|
#include <nuttx/net/ip.h>
|
|
#include <nuttx/net/icmpv6.h>
|
|
|
|
#include "netdev/netdev.h"
|
|
#include "devif/devif.h"
|
|
#include "inet/inet.h"
|
|
#include "neighbor/neighbor.h"
|
|
#include "route/route.h"
|
|
#include "icmpv6/icmpv6.h"
|
|
|
|
#ifdef CONFIG_NET_ICMPv6_NEIGHBOR
|
|
|
|
/****************************************************************************
|
|
* Private Types
|
|
****************************************************************************/
|
|
|
|
/* This structure holds the state of the send operation until it can be
|
|
* operated upon from the event handler.
|
|
*/
|
|
|
|
struct icmpv6_neighbor_s
|
|
{
|
|
FAR struct devif_callback_s *snd_cb; /* Reference to callback instance */
|
|
sem_t snd_sem; /* Used to wake up the waiting thread */
|
|
uint8_t snd_retries; /* Retry count */
|
|
volatile bool snd_sent; /* True: if request sent */
|
|
uint8_t snd_ifname[IFNAMSIZ]; /* Interface name */
|
|
net_ipv6addr_t snd_ipaddr; /* The IPv6 address to be queried */
|
|
};
|
|
|
|
/****************************************************************************
|
|
* Private Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: icmpv6_neighbor_eventhandler
|
|
****************************************************************************/
|
|
|
|
static uint16_t icmpv6_neighbor_eventhandler(FAR struct net_driver_s *dev,
|
|
FAR void *priv, uint16_t flags)
|
|
{
|
|
FAR struct icmpv6_neighbor_s *state = (FAR struct icmpv6_neighbor_s *)priv;
|
|
|
|
ninfo("flags: %04x sent: %d\n", flags, state->snd_sent);
|
|
|
|
if (state)
|
|
{
|
|
/* Is this the device that we need to route this request? */
|
|
|
|
if (strncmp((FAR const char *)dev->d_ifname,
|
|
(FAR const char *)state->snd_ifname, IFNAMSIZ) != 0)
|
|
{
|
|
/* No... pass on this one and wait for the device that we want */
|
|
|
|
return flags;
|
|
}
|
|
|
|
/* Check if the outgoing packet is available. It may have been claimed
|
|
* by a send event handler serving a different thread -OR- if the
|
|
* output buffer currently contains unprocessed incoming data. In
|
|
* these cases we will just have to wait for the next polling cycle.
|
|
*/
|
|
|
|
if (dev->d_sndlen > 0 || (flags & ICMPv6_NEWDATA) != 0)
|
|
{
|
|
/* Another thread has beat us sending data or the buffer is busy,
|
|
* Check for a timeout. If not timed out, wait for the next
|
|
* polling cycle and check again.
|
|
*/
|
|
|
|
/* REVISIT: No timeout. Just wait for the next polling cycle */
|
|
|
|
return flags;
|
|
}
|
|
|
|
/* Prepare device buffer */
|
|
|
|
if (netdev_iob_prepare(dev, false, 0) != OK)
|
|
{
|
|
return flags;
|
|
}
|
|
|
|
/* It looks like we are good to send the data.
|
|
*
|
|
* Copy the packet data into the device packet buffer and send it.
|
|
*/
|
|
|
|
icmpv6_solicit(dev, state->snd_ipaddr);
|
|
|
|
IFF_SET_IPv6(dev->d_flags);
|
|
|
|
/* Don't allow any further call backs. */
|
|
|
|
state->snd_sent = true;
|
|
state->snd_cb->flags = 0;
|
|
state->snd_cb->priv = NULL;
|
|
state->snd_cb->event = NULL;
|
|
|
|
/* Wake up the waiting thread */
|
|
|
|
nxsem_post(&state->snd_sem);
|
|
}
|
|
|
|
return flags;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Public Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: icmpv6_neighbor
|
|
*
|
|
* Description:
|
|
* The icmpv6_solicit() call may be to send an ICMPv6 Neighbor
|
|
* Solicitation to resolve an IPv6 address. This function first checks if
|
|
* the IPv6 address is already in the Neighbor Table. If so, then it
|
|
* returns success immediately.
|
|
*
|
|
* If the requested IPv6 address in not in the Neighbor Table, then this
|
|
* function will send the Neighbor Solicitation, delay, then check if the
|
|
* IP address is now in the Neighbor able. It will repeat this sequence
|
|
* until either (1) the IPv6 address mapping is now in the Neighbor table,
|
|
* or (2) a configurable number of timeouts occur without receiving the
|
|
* ICMPv6 Neighbor Advertisement.
|
|
*
|
|
* Input Parameters:
|
|
* ipaddr The IPv6 address to be queried.
|
|
*
|
|
* Returned Value:
|
|
* Zero (OK) is returned on success and the IP address mapping can now be
|
|
* found in the Neighbor Table. On error a negated errno value is
|
|
* returned:
|
|
*
|
|
* -ETIMEDOUT: The number or retry counts has been exceed.
|
|
* -EHOSTUNREACH: Could not find a route to the host
|
|
*
|
|
* Assumptions:
|
|
* This function is called from the normal tasking context.
|
|
*
|
|
****************************************************************************/
|
|
|
|
int icmpv6_neighbor(const net_ipv6addr_t ipaddr)
|
|
{
|
|
FAR struct net_driver_s *dev;
|
|
struct icmpv6_notify_s notify;
|
|
struct icmpv6_neighbor_s state;
|
|
net_ipv6addr_t lookup;
|
|
int ret;
|
|
|
|
/* First check if destination is a local broadcast or a multicast address.
|
|
*
|
|
* - IPv6 multicast addresses are have the high-order octet of the
|
|
* addresses=0xff (ff00::/8.)
|
|
*/
|
|
|
|
if (net_ipv6addr_cmp(ipaddr, g_ipv6_unspecaddr) ||
|
|
net_is_addr_mcast(ipaddr))
|
|
{
|
|
/* We don't need to send the Neighbor Solicitation. But for the case
|
|
* of the Multicast address, a routing able entry will be required.
|
|
*/
|
|
|
|
return OK;
|
|
}
|
|
|
|
/* Get the device that can route this request */
|
|
|
|
dev = netdev_findby_ripv6addr(g_ipv6_unspecaddr, ipaddr);
|
|
if (!dev)
|
|
{
|
|
nerr("ERROR: Unreachable: %08lx\n", (unsigned long)ipaddr);
|
|
ret = -EHOSTUNREACH;
|
|
goto errout;
|
|
}
|
|
|
|
/* Check if the destination address is on the local network. */
|
|
|
|
if (net_ipv6addr_maskcmp(ipaddr, dev->d_ipv6addr, dev->d_ipv6netmask))
|
|
{
|
|
/* Yes.. use the input address for the lookup */
|
|
|
|
net_ipv6addr_copy(lookup, ipaddr);
|
|
}
|
|
else
|
|
{
|
|
/* Destination address is not on the local network */
|
|
|
|
#ifdef CONFIG_NET_ROUTE
|
|
|
|
/* We have a routing table.. find the correct router to use in
|
|
* this case (or, as a fall-back, use the device's default router
|
|
* address). We will use the router IP address instead of the
|
|
* destination address when determining the MAC address.
|
|
*/
|
|
|
|
netdev_ipv6_router(dev, ipaddr, lookup);
|
|
#else
|
|
/* Use the device's default router IP address instead of the
|
|
* destination address when determining the MAC address.
|
|
*/
|
|
|
|
net_ipv6addr_copy(lookup, dev->d_ipv6draddr);
|
|
#endif
|
|
}
|
|
|
|
/* Allocate resources to receive a callback. This and the following
|
|
* initialization is performed with the network lock because we don't
|
|
* want anything to happen until we are ready.
|
|
*/
|
|
|
|
net_lock();
|
|
state.snd_cb = devif_callback_alloc((dev),
|
|
&(dev)->d_conncb,
|
|
&(dev)->d_conncb_tail);
|
|
if (!state.snd_cb)
|
|
{
|
|
nerr("ERROR: Failed to allocate a callback\n");
|
|
ret = -ENOMEM;
|
|
goto errout_with_lock;
|
|
}
|
|
|
|
nxsem_init(&state.snd_sem, 0, 0); /* Doesn't really fail */
|
|
|
|
state.snd_retries = 0; /* No retries yet */
|
|
net_ipv6addr_copy(state.snd_ipaddr, lookup); /* IP address to query */
|
|
|
|
/* Remember the routing device name */
|
|
|
|
strlcpy((FAR char *)state.snd_ifname, (FAR const char *)dev->d_ifname,
|
|
IFNAMSIZ);
|
|
|
|
/* Now loop, testing if the address mapping is in the Neighbor Table and
|
|
* re-sending the Neighbor Solicitation if it is not.
|
|
*/
|
|
|
|
ret = -ETIMEDOUT; /* Assume a timeout failure */
|
|
|
|
while (state.snd_retries < CONFIG_ICMPv6_NEIGHBOR_MAXTRIES)
|
|
{
|
|
/* Check if the address mapping is present in the Neighbor Table. This
|
|
* is only really meaningful on the first time through the loop.
|
|
*
|
|
* NOTE: If the Neighbor Table is large than this could be a
|
|
* performance issue.
|
|
*/
|
|
|
|
if (neighbor_lookup(lookup, NULL) >= 0)
|
|
{
|
|
/* We have it! Break out with success */
|
|
|
|
ret = OK;
|
|
break;
|
|
}
|
|
|
|
/* Set up the Neighbor Advertisement wait BEFORE we send the Neighbor
|
|
* Solicitation.
|
|
*/
|
|
|
|
icmpv6_wait_setup(lookup, ¬ify);
|
|
|
|
/* Arm/re-arm the callback */
|
|
|
|
state.snd_sent = false;
|
|
state.snd_cb->flags = ICMPv6_POLL;
|
|
state.snd_cb->priv = (FAR void *)&state;
|
|
state.snd_cb->event = icmpv6_neighbor_eventhandler;
|
|
|
|
/* Notify the device driver that new TX data is available. */
|
|
|
|
netdev_txnotify_dev(dev);
|
|
|
|
/* Wait for the send to complete or an error to occur.
|
|
* net_sem_wait will also terminate if a signal is received.
|
|
*/
|
|
|
|
do
|
|
{
|
|
net_sem_wait(&state.snd_sem);
|
|
}
|
|
while (!state.snd_sent);
|
|
|
|
/* Now wait for response to the Neighbor Advertisement to be
|
|
* received.
|
|
*/
|
|
|
|
ret = icmpv6_wait(¬ify, CONFIG_ICMPv6_NEIGHBOR_DELAYMSEC);
|
|
|
|
/* icmpv6_wait will return OK if and only if the matching Neighbor
|
|
* Advertisement is received. Otherwise, it will return -ETIMEDOUT.
|
|
*/
|
|
|
|
if (ret == OK)
|
|
{
|
|
break;
|
|
}
|
|
|
|
/* Increment the retry count */
|
|
|
|
state.snd_retries++;
|
|
}
|
|
|
|
nxsem_destroy(&state.snd_sem);
|
|
devif_dev_callback_free(dev, state.snd_cb);
|
|
|
|
errout_with_lock:
|
|
net_unlock();
|
|
|
|
errout:
|
|
return ret;
|
|
}
|
|
|
|
#endif /* CONFIG_NET_ICMPv6_NEIGHBOR */
|