incubator-nuttx/net/mld/mld_join.c

255 lines
7.9 KiB
C

/****************************************************************************
* net/mld/mld_join.c
*
* Copyright (C) 2018 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 of CITEL Technologies Ltd 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 CITEL TECHNOLOGIES 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 CITEL TECHNOLOGIES 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 <assert.h>
#include <debug.h>
#include <netinet/in.h>
#include <nuttx/net/netconfig.h>
#include <nuttx/net/netstats.h>
#include <nuttx/net/ip.h>
#include <nuttx/net/mld.h>
#include "netdev/netdev.h"
#include "mld/mld.h"
#ifdef CONFIG_NET_MLD
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: mld_group_startup
*
* Description:
* Set up the startup actions when the first member from this host joins
* the group.
*
* Assumptions:
* The network is locked.
*
****************************************************************************/
static int mld_group_startup(FAR const struct ipv6_mreq *mrec,
FAR struct net_driver_s *dev,
FAR struct mld_group_s *group)
{
int ret;
/* Send the Version 2 Multicast Listener Report (Assumes MLDv2 mode
* initially).
*/
MLD_STATINCR(g_netstats.mld.report_sched);
ret = mld_waitmsg(group, MLD_SEND_V2REPORT);
if (ret < 0)
{
mlderr("ERROR: Failed to schedule Report: %d\n", ret);
return ret;
}
/* And start the timer at 1 second */
SET_MLD_STARTUP(group->flags);
group->count = MLD_UNSOLREPORT_COUNT - 1;
mld_start_polltimer(group, MSEC2TICK(MLD_UNSOLREPORT_MSEC));
/* Add the group (MAC) address to the Ethernet drivers MAC filter list */
mld_addmcastmac(dev, mrec->ipv6mr_multiaddr.s6_addr16);
return OK;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: mld_joingroup
*
* Description:
* Add the specified group address to the group. This function
* implements the logic for the IPV6_JOIN_GROUP socket option.
*
* The IPV6_JOIN_GROUP socket option is used to join a multicast group.
* This is accomplished by using the setsockopt() API and specifying the
* address of the ipv6_mreq structure containing the IPv6 multicast address
* and the local IPv6 multicast interface index. The stack chooses a
* default multicast interface if an interface index of 0 is passed. The
* values specified in the IPV6_MREQ structure used by IPV6_JOIN_GROUP
* and IPV6_LEAVE_GROUP must be symmetrical. The format of the ipv6_mreq
* structure can be found in include/netinet/in.h
*
* Assumptions:
* The network is locked.
*
****************************************************************************/
int mld_joingroup(FAR const struct ipv6_mreq *mrec)
{
FAR struct net_driver_s *dev;
FAR struct mld_group_s *group;
int ret;
DEBUGASSERT(mrec != NULL);
/* Assure that the group address is an IPv6 multicast address */
if (!net_is_addr_mcast(mrec->ipv6mr_multiaddr.s6_addr16))
{
return -EINVAL;
}
/* Get the device from the interface index. Use the default network device
* if an interface index of 0 is provided.
*/
if (mrec->ipv6mr_interface == 0)
{
dev = netdev_default();
}
else
{
dev = netdev_findbyindex(mrec->ipv6mr_interface);
}
if (dev == NULL)
{
mlderr("ERROR: No device for this interface index: %u\n",
mrec->ipv6mr_interface);
return -ENODEV;
}
mldinfo("Join group: %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
mrec->ipv6mr_multiaddr.s6_addr16[0],
mrec->ipv6mr_multiaddr.s6_addr16[1],
mrec->ipv6mr_multiaddr.s6_addr16[2],
mrec->ipv6mr_multiaddr.s6_addr16[3],
mrec->ipv6mr_multiaddr.s6_addr16[4],
mrec->ipv6mr_multiaddr.s6_addr16[5],
mrec->ipv6mr_multiaddr.s6_addr16[5],
mrec->ipv6mr_multiaddr.s6_addr16[7]);
/* Check if a this address is already in the group */
group = mld_grpfind(dev, mrec->ipv6mr_multiaddr.s6_addr16);
if (group == NULL)
{
/* No... allocate a new entry */
mldinfo("Allocate new group entry\n");
group = mld_grpalloc(dev, mrec->ipv6mr_multiaddr.s6_addr16);
if (group == NULL)
{
return -ENOMEM;
}
/* Indicate one request to join the group from this this host */
group->njoins = 1;
/* Set up the group startup operations */
ret = mld_group_startup(mrec, dev, group);
if (ret < 0)
{
mlderr("ERROR: Failed to start group: %d\n", ret);
mld_grpfree(dev, group);
return ret;
}
MLD_STATINCR(g_netstats.mld.njoins);
/* REVISIT: It is expected that higher level logic will set up
* the routing table entry for the new multicast address. That
* is not done here.
*/
}
else
{
/* The group already exists; a task from this host is joining an
* existing group.
*/
mldinfo("Join existing group\n");
#ifdef CONFIG_NET_MLD_ROUTER
/* In the Router case this could still be the first join from this
* host. If this is the first join from this host, then we need to
* perform the group startup operations.
*/
if (group->join == 0)
{
/* This is the for join from this host. Perform out start up
* operations.
*/
ret = mld_group_startup(mrec, dev, group);
if (ret < 0)
{
mlderr("ERROR: Failed to start group: %d\n", ret);
mld_grpfree(dev, group);
return ret;
}
}
#else
/* Not a router? Then there must be another join from this host or
* how could the group have been created?
*/
DEBUGASSERT(group->njoins > 0);
#endif
/* Indicate one more request to join the group from this this host */
DEBUGASSERT(group->njoins < UINT8_MAX);
group->njoins++;
MLD_STATINCR(g_netstats.mld.njoins);
}
return OK;
}
#endif /* CONFIG_NET_MLD */