198 lines
7.6 KiB
C
198 lines
7.6 KiB
C
/****************************************************************************
|
|
* net/igmp/igmp_leave.c
|
|
*
|
|
* SPDX-License-Identifier: BSD-3-Clause
|
|
*
|
|
* Copyright (C) 2010-2011, 2014, 2018 Gregory Nutt. All rights reserved.
|
|
* Author: Gregory Nutt <gnutt@nuttx.org>
|
|
*
|
|
* The NuttX implementation of IGMP was inspired by the IGMP add-on for the
|
|
* lwIP TCP/IP stack by Steve Reynolds:
|
|
*
|
|
* Copyright (c) 2002 CITEL Technologies Ltd.
|
|
* 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. 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/wdog.h>
|
|
#include <nuttx/net/netconfig.h>
|
|
#include <nuttx/net/net.h>
|
|
#include <nuttx/net/netstats.h>
|
|
#include <nuttx/net/ip.h>
|
|
#include <nuttx/net/igmp.h>
|
|
|
|
#include "devif/devif.h"
|
|
#include "igmp/igmp.h"
|
|
|
|
#ifdef CONFIG_NET_IGMP
|
|
|
|
/****************************************************************************
|
|
* Public Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: igmp_leavegroup
|
|
*
|
|
* Description:
|
|
* Remove the specified group address to the group.
|
|
*
|
|
* RFC 2236, 3. Protocol Description:
|
|
*
|
|
* "When a host leaves a multicast group, if it was the last host to
|
|
* reply to a Query with a Membership Report for that group, it SHOULD
|
|
* send a Leave Group message to the all-routers multicast group
|
|
* (224.0.0.2). If it was not the last host to reply to a Query, it MAY
|
|
* send nothing as there must be another member on the subnet. This is
|
|
* an optimization to reduce traffic; a host without sufficient storage
|
|
* to remember whether or not it was the last host to reply MAY always
|
|
* send a Leave Group message when it leaves a group. Routers SHOULD
|
|
* accept a Leave Group message addressed to the group being left, in
|
|
* order to accommodate implementations of an earlier version of this
|
|
* standard. Leave Group messages are addressed to the all-routers
|
|
* group because other group members have no need to know that a host
|
|
* has left the group, but it does no harm to address the message to the
|
|
* group."
|
|
*
|
|
* ________________
|
|
* | |
|
|
* | |
|
|
* | |
|
|
* | |
|
|
* +--------->| Non-Member |<---------+
|
|
* | | | |
|
|
* | | | |
|
|
* | | | |
|
|
* | |________________| |
|
|
* | | |
|
|
* | leave group | join group | leave group
|
|
* | (stop timer, |(send report, | (send leave
|
|
* | send leave if | set flag, | if flag set)
|
|
* | flag set) | start timer) |
|
|
* ________|________ | ________|________
|
|
* | |<---------+ | |
|
|
* | | | |
|
|
* | |<-------------------| |
|
|
* | | query received | |
|
|
* | Delaying Member | (start timer) | Idle Member |
|
|
* +---->| |------------------->| |
|
|
* | | | report received | |
|
|
* | | | (stop timer, | |
|
|
* | | | clear flag) | |
|
|
* | |_________________|------------------->|_________________|
|
|
* | query received | timer expired
|
|
* | (reset timer if | (send report,
|
|
* | Max Resp Time | set flag)
|
|
* | < current timer) |
|
|
* +-------------------+
|
|
*
|
|
* Assumptions:
|
|
* The network is locked.
|
|
*
|
|
****************************************************************************/
|
|
|
|
int igmp_leavegroup(struct net_driver_s *dev,
|
|
FAR const struct in_addr *grpaddr)
|
|
{
|
|
struct igmp_group_s *group;
|
|
int ret;
|
|
|
|
DEBUGASSERT(dev && grpaddr);
|
|
|
|
/* Find the entry corresponding to the address leaving the group */
|
|
|
|
group = igmp_grpfind(dev, &grpaddr->s_addr);
|
|
ninfo("Leaving group: %p\n", group);
|
|
if (group)
|
|
{
|
|
DEBUGASSERT(group->njoins > 0);
|
|
group->njoins--;
|
|
|
|
/* Take no further actions if there are other members of this group
|
|
* on this host.
|
|
*/
|
|
|
|
if (group->njoins > 0)
|
|
{
|
|
return OK;
|
|
}
|
|
|
|
/* Cancel the timer and discard any queued Membership Reports.
|
|
* Canceling the timer will prevent any new Membership Reports from
|
|
* being sent; clearing the flags will discard any pending Membership
|
|
* Reports that could interfere with the Leave Group.
|
|
*/
|
|
|
|
wd_cancel(&group->wdog);
|
|
CLR_SCHEDMSG(group->flags);
|
|
CLR_WAITMSG(group->flags);
|
|
|
|
IGMP_STATINCR(g_netstats.igmp.leaves);
|
|
|
|
/* Send a leave if the flag is set according to the state diagram */
|
|
|
|
if (IFF_IS_UP(dev->d_flags) && IS_LASTREPORT(group->flags))
|
|
{
|
|
ninfo("Schedule Leave Group message\n");
|
|
IGMP_STATINCR(g_netstats.igmp.leave_sched);
|
|
|
|
ret = igmp_waitmsg(group, IGMP_LEAVE_GROUP);
|
|
if (ret < 0)
|
|
{
|
|
nerr("ERROR: Failed to schedule message: %d\n", ret);
|
|
}
|
|
}
|
|
|
|
/* Free the group structure (state is now Non-Member */
|
|
|
|
igmp_grpfree(dev, group);
|
|
|
|
/* And remove the group address from the drivers MAC filter set */
|
|
|
|
igmp_removemcastmac(dev, (FAR in_addr_t *)&grpaddr->s_addr);
|
|
return OK;
|
|
}
|
|
|
|
/* Return ENOENT if the address is not a member of the group */
|
|
|
|
ninfo("Return -ENOENT\n");
|
|
return -ENOENT;
|
|
}
|
|
|
|
#endif /* CONFIG_NET_IGMP */
|