nuttx/net/arp/arp_send.c

417 lines
13 KiB
C

/****************************************************************************
* net/arp/arp_send.c
*
* Copyright (C) 2014-2016 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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 <nuttx/config.h>
#include <unistd.h>
#include <string.h>
#include <semaphore.h>
#include <time.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/arp.h>
#include "netdev/netdev.h"
#include "devif/devif.h"
#include "route/route.h"
#include "arp/arp.h"
#ifdef CONFIG_NET_ARP_SEND
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#define CONFIG_ARP_SEND_DELAYSEC \
(CONFIG_ARP_SEND_DELAYMSEC / 1000)
#define CONFIG_ARP_SEND_DELAYNSEC \
((CONFIG_ARP_SEND_DELAYMSEC - 1000*CONFIG_ARP_SEND_DELAYSEC) * 1000000)
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: arp_send_terminate
****************************************************************************/
static void arp_send_terminate(FAR struct arp_send_s *state, int result)
{
/* Don't allow any further call backs. */
state->snd_sent = true;
state->snd_result = (int16_t)result;
state->snd_cb->flags = 0;
state->snd_cb->priv = NULL;
state->snd_cb->event = NULL;
/* Wake up the waiting thread */
sem_post(&state->snd_sem);
}
/****************************************************************************
* Name: arp_send_interrupt
****************************************************************************/
static uint16_t arp_send_interrupt(FAR struct net_driver_s *dev,
FAR void *pvconn,
FAR void *priv, uint16_t flags)
{
FAR struct arp_send_s *state = (FAR struct arp_send_s *)priv;
ninfo("flags: %04x sent: %d\n", flags, state->snd_sent);
if (state)
{
/* Check if the network is still up */
if ((flags & NETDEV_DOWN) != 0)
{
nerr("ERROR: Interface is down\n");
arp_send_terminate(state, -ENETUNREACH);
return flags;
}
/* Check if the outgoing packet is available. It may have been claimed
* by a send interrupt 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 & PKT_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;
}
/* It looks like we are good to send the data */
/* Copy the packet data into the device packet buffer and send it */
arp_format(dev, state->snd_ipaddr);
/* Make sure no ARP request overwrites this ARP request. This
* flag will be cleared in arp_out().
*/
IFF_SET_NOARP(dev->d_flags);
/* Don't allow any further call backs. */
arp_send_terminate(state, OK);
}
return flags;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: arp_send
*
* Description:
* The arp_send() call may be to send an ARP request to resolve an IP
* address. This function first checks if the IP address is already in
* ARP table. If so, then it returns success immediately.
*
* If the requested IP address in not in the ARP table, then this function
* will send an ARP request, delay, then check if the IP address is now in
* the ARP table. It will repeat this sequence until either (1) the IP
* address mapping is now in the ARP table, or (2) a configurable number
* of timeouts occur without receiving the ARP replay.
*
* Parameters:
* ipaddr The IP address to be queried (in network order).
*
* Returned Value:
* Zero (OK) is returned on success and the IP address mapping can now be
* found in the ARP 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 arp_send(in_addr_t ipaddr)
{
FAR struct net_driver_s *dev;
struct arp_notify_s notify;
struct timespec delay;
struct arp_send_s state;
int ret;
/* First check if destination is a local broadcast. */
if (ipaddr == INADDR_BROADCAST)
{
/* We don't need to send the ARP request */
return OK;
}
#ifdef CONFIG_NET_IGMP
/* Check if the destination address is a multicast address
*
* - IPv4: multicast addresses lie in the class D group -- The address range
* 224.0.0.0 to 239.255.255.255 (224.0.0.0/4)
*
* - IPv6 multicast addresses are have the high-order octet of the
* addresses=0xff (ff00::/8.)
*/
if (NTOHL(ipaddr) >= 0xe0000000 && NTOHL(ipaddr) <= 0xefffffff)
{
/* We don't need to send the ARP request */
return OK;
}
#endif
/* Get the device that can route this request */
#ifdef CONFIG_NETDEV_MULTINIC
dev = netdev_findby_ipv4addr(INADDR_ANY, ipaddr);
#else
dev = netdev_findby_ipv4addr(ipaddr);
#endif
if (!dev)
{
nerr("ERROR: Unreachable: %08lx\n", (unsigned long)ipaddr);
ret = -EHOSTUNREACH;
goto errout;
}
#ifdef CONFIG_NET_MULTILINK
/* ARP support is only built if the Ethernet data link is supported.
* However, if we are supporting multiple network devices and using
* different link level protocols then we can get here for other
* link protocols as well. Continue and send the ARP request only
* if this device uses the Ethernet data link protocol.
*/
if (dev->d_lltype != NET_LL_ETHERNET)
{
return OK;
}
#endif
/* Check if the destination address is on the local network. */
if (!net_ipv4addr_maskcmp(ipaddr, dev->d_ipaddr, dev->d_netmask))
{
in_addr_t dripaddr;
/* 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_ipv4_router(dev, ipaddr, &dripaddr);
#else
/* Use the device's default router IP address instead of the
* destination address when determining the MAC address.
*/
net_ipv4addr_copy(dripaddr, dev->d_draddr);
#endif
ipaddr = dripaddr;
}
/* 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 = arp_callback_alloc(dev);
if (!state.snd_cb)
{
nerr("ERROR: Failed to allocate a callback\n");
ret = -ENOMEM;
goto errout_with_lock;
}
/* Initialize the state structure. This is done with interrupts
* disabled
*/
/* This semaphore is used for signaling and, hence, should not have
* priority inheritance enabled.
*/
(void)sem_init(&state.snd_sem, 0, 0); /* Doesn't really fail */
sem_setprotocol(&state.snd_sem, SEM_PRIO_NONE);
state.snd_retries = 0; /* No retries yet */
state.snd_ipaddr = ipaddr; /* IP address to query */
#ifdef CONFIG_NETDEV_MULTINIC
/* Remember the routing device name */
strncpy((FAR char *)state.snd_ifname, (FAR const char *)dev->d_ifname, IFNAMSIZ);
#endif
/* Now loop, testing if the address mapping is in the ARP table and re-sending the ARP request if it is not.
*/
ret = -ETIMEDOUT; /* Assume a timeout failure */
while (state.snd_retries < CONFIG_ARP_SEND_MAXTRIES)
{
/* Check if the address mapping is present in the ARP table. This
* is only really meaningful on the first time through the loop.
*
* NOTE: If the ARP table is large than this could be a performance
* issue.
*/
if (arp_find(ipaddr))
{
/* We have it! Break out with success */
ret = OK;
break;
}
/* Set up the ARP response wait BEFORE we send the ARP request */
arp_wait_setup(ipaddr, &notify);
/* Arm/re-arm the callback */
state.snd_sent = false;
state.snd_result = -EBUSY;
state.snd_cb->flags = (ARP_POLL | NETDEV_DOWN);
state.snd_cb->priv = (FAR void *)&state;
state.snd_cb->event = arp_send_interrupt;
/* Notify the device driver that new TX data is available.
* NOTES: This is in essence what netdev_ipv4_txnotify() does, which
* is not possible to call since it expects a in_addr_t as
* its single argument to lookup the network interface.
*/
if (dev->d_txavail)
{
dev->d_txavail(dev);
}
/* Wait for the send to complete or an error to occur: NOTES: (1)
* net_lockedwait will also terminate if a signal is received, (2)
* interrupts may be disabled! They will be re-enabled while the
* task sleeps and automatically re-enabled when the task restarts.
*/
do
{
(void)net_lockedwait(&state.snd_sem);
}
while (!state.snd_sent);
/* Check the result of the send operation */
ret = state.snd_result;
if (ret < 0)
{
/* Break out on a send failure */
nerr("ERROR: Send failed: %d\n", ret);
break;
}
/* Now wait for response to the ARP response to be received. The
* optimal delay would be the work case round trip time.
* NOTE: The network is locked.
*/
delay.tv_sec = CONFIG_ARP_SEND_DELAYSEC;
delay.tv_nsec = CONFIG_ARP_SEND_DELAYNSEC;
ret = arp_wait(&notify, &delay);
/* arp_wait will return OK if and only if the matching ARP response
* is received. Otherwise, it will return -ETIMEDOUT.
*/
if (ret >= OK)
{
/* Break out if arp_wait() fails */
break;
}
/* Increment the retry count */
state.snd_retries++;
nerr("ERROR: arp_wait failed: %d\n", ret);
}
sem_destroy(&state.snd_sem);
arp_callback_free(dev, state.snd_cb);
errout_with_lock:
net_unlock();
errout:
return ret;
}
#endif /* CONFIG_NET_ARP_SEND */