incubator-nuttx/net/mld/mld_group.c

318 lines
9.1 KiB
C

/****************************************************************************
* net/mld/mld_group.c
* MLD group data structure management logic
*
* 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 <nuttx/compiler.h>
#include <stdlib.h>
#include <string.h>
#include <queue.h>
#include <debug.h>
#include <arch/irq.h>
#include <nuttx/arch.h>
#include <nuttx/wdog.h>
#include <nuttx/kmalloc.h>
#include <nuttx/semaphore.h>
#include <nuttx/net/net.h>
#include <nuttx/net/netdev.h>
#include <nuttx/net/ip.h>
#include <nuttx/net/mld.h>
#include "devif/devif.h"
#include "mld/mld.h"
#ifdef CONFIG_NET_MLD
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: mld_ngroups
*
* Description:
* Return the number of groups joined by applications.
*
****************************************************************************/
static int mld_ngroups(FAR struct net_driver_s *dev)
{
FAR struct mld_group_s *group;
int ngroups = 0;
/* Count the number of groups in the group list */
for (group = (FAR struct mld_group_s *)dev->d_mld.grplist.head;
group != NULL;
group = group->next)
{
ngroups++;
}
/* REVISIT: Subtract one for the IPv6 allnodes group. Why is this here?
* what do we need it for? It was cloned from IGMP and is probably not
* needed.
*/
return ngroups > 0 ? ngroups - 1 : 0;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: mld_grpalloc
*
* Description:
* Allocate a new group from heap memory.
*
* Assumptions:
* The network is locked.
*
****************************************************************************/
FAR struct mld_group_s *mld_grpalloc(FAR struct net_driver_s *dev,
FAR const net_ipv6addr_t addr)
{
FAR struct mld_group_s *group;
mldinfo("addr: %08x dev: %p\n", *addr, dev);
group = (FAR struct mld_group_s *)kmm_zalloc(sizeof(struct mld_group_s));
mldinfo("group: %p\n", group);
/* Check if we successfully allocated a group structure */
if (group != NULL)
{
/* Initialize the non-zero elements of the group structure */
net_ipv6addr_copy(group->grpaddr, addr);
/* This semaphore is used for signaling and, hence, should not have
* priority inheritance enabled.
*/
nxsem_init(&group->sem, 0, 0);
nxsem_setprotocol(&group->sem, SEM_PRIO_NONE);
/* Initialize the group timers */
group->polldog = wd_create();
DEBUGASSERT(group->polldog != NULL);
if (group->polldog == NULL)
{
goto errout_with_sem;
}
/* Save the interface index */
group->ifindex = dev->d_ifindex;
#ifndef CONFIG_NET_MLD_ROUTER
/* Start the query timer if we are the Querier and this is the first
* group member of the group.
*/
if (mld_ngroups(dev) == 0)
{
mld_start_gentimer(dev, MSEC2TICK(MLD_QUERY_MSEC));
}
#endif
/* Add the group structure to the list in the device structure */
sq_addfirst((FAR sq_entry_t *)group, &dev->d_mld.grplist);
}
return group;
errout_with_sem:
(void)nxsem_destroy(&group->sem);
kmm_free(group);
return NULL;
}
/****************************************************************************
* Name: mld_grpfind
*
* Description:
* Find an existing group.
*
* Assumptions:
* The network is locked.
*
****************************************************************************/
FAR struct mld_group_s *mld_grpfind(FAR struct net_driver_s *dev,
FAR const net_ipv6addr_t addr)
{
FAR struct mld_group_s *group;
mldinfo("Searching for group: %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
addr[0], addr[1], addr[2], addr[3], addr[4], addr[5], addr[6],
addr[7]);
for (group = (FAR struct mld_group_s *)dev->d_mld.grplist.head;
group;
group = group->next)
{
mldinfo("Compare: %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
group->grpaddr[0], group->grpaddr[1], group->grpaddr[2],
group->grpaddr[3], group->grpaddr[4], group->grpaddr[5],
group->grpaddr[6], group->grpaddr[7]);
if (net_ipv6addr_cmp(group->grpaddr, addr))
{
mldinfo("Match!\n");
DEBUGASSERT(group->ifindex == dev->d_ifindex);
break;
}
}
return group;
}
/****************************************************************************
* Name: mld_grpallocfind
*
* Description:
* Find an existing group. If not found, create a new group for the
* address.
*
****************************************************************************/
FAR struct mld_group_s *mld_grpallocfind(FAR struct net_driver_s *dev,
FAR const net_ipv6addr_t addr)
{
FAR struct mld_group_s *group = mld_grpfind(dev, addr);
mldinfo("group: %p addr: %08x\n", group, (int)*addr);
if (!group)
{
group = mld_grpalloc(dev, addr);
}
mldinfo("group: %p\n", group);
return group;
}
/****************************************************************************
* Name: mld_grpfree
*
* Description:
* Release a previously allocated group.
*
* Assumptions:
* The network is locked.
*
****************************************************************************/
void mld_grpfree(FAR struct net_driver_s *dev, FAR struct mld_group_s *group)
{
mldinfo("Free: %p flags: %02x\n", group, group->flags);
/* Cancel the timers */
wd_cancel(group->polldog);
/* Remove the group structure from the group list in the device structure */
sq_rem((FAR sq_entry_t *)group, &dev->d_mld.grplist);
/* Destroy the wait semaphore */
(void)nxsem_destroy(&group->sem);
/* Destroy the timers */
wd_delete(group->polldog);
/* Then release the group structure resources. */
mldinfo("Call sched_kfree()\n");
kmm_free(group);
#ifndef CONFIG_NET_MLD_ROUTER
/* If there are no longer any groups, then stop the general query and v1
* compatibility timers.
*/
if (mld_ngroups(dev) == 0)
{
wd_cancel(dev->d_mld.gendog);
wd_cancel(dev->d_mld.v1dog);
}
#endif
}
/****************************************************************************
* Name: mld_new_pollcycle
*
* Description:
* Update accumulated membership at the beginning of each new poll cycle
*
****************************************************************************/
#ifdef CONFIG_NET_MLD_ROUTER
void mld_new_pollcycle(FAR struct net_driver_s *dev)
{
FAR struct mld_group_s *member;
/* Update member ship in every group */
for (member = (FAR struct mld_group_s *)dev->d_mld.grplist.head;
member;
member = member->next)
{
/* Save the number of members that reported in the previous query
* cycle; reset the number of members that have reported in the new
* query cycle.
*/
member->lstmbrs = member->members;
member->members = 0;
}
}
#endif
#endif /* CONFIG_NET_MLD */