/**************************************************************************** * net/mld/mld_leave.c * * Copyright (C) 2018 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * 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 #include #include #include #include #include #include #include #include #include #include "netdev/netdev.h" #include "mld/mld.h" #ifdef CONFIG_NET_MLD /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: mld_leavegroup * * Description: * Remove the specified group address to the group. This function * implements the logic for the IPV6_LEAVE_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 * * State transition diagram for a router in Querier state (RFC 2710): * ________________ * | | * | |timer expired * timer expired| |(notify routing -, * (notify routing -)| No Listeners |clear rxmt tmr) * ------->| Present |<--------- * | | | | * | | | | * | |________________| | --------------- * | | | | rexmt timer | * | report received| | | expired | * | (notify routing +,| | | (send m-a-s | * | start timer)| | | query, | * __________|______ | ________|_|______ st rxmt | * | |<------------ | | tmr) | * | | | |<------- * | | report received | | * | | (start timer, | | * | | clear rxmt tmr) | | * | Listeners |<-------------------| Checking | * | Present | done received | Listeners | * | | (start timer*, | | * | | start rxmt timer, | | * | | send m-a-s query) | | * --->| |------------------->| | * | |_________________| |_________________| * | report received | * | (start timer) | * ----------------- * * State transition diagram for a router in Non-Querier state is * similar, but non-Queriers do not send any messages and are only * driven by message reception (See RFC 2710/3810 or net/mld.h). * ****************************************************************************/ int mld_leavegroup(FAR const struct ipv6_mreq *mrec) { FAR struct net_driver_s *dev; struct mld_group_s *group; DEBUGASSERT(dev != NULL && mrec != NULL); /* 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) { return -ENODEV; } ninfo("Leave 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); /* Find the entry corresponding to the address leaving the group */ group = mld_grpfind(dev, mrec->ipv6mr_multiaddr.s6_addr16); if (group != NULL) { ninfo("Leaving group: %p\n", group); /* Cancel the timer and discard any queued Reports. Canceling the * timer will prevent any new Reports from being sent; clearing the * flags will discard any pending Reports that could interfere with * leaving the group. */ net_lock(); wd_cancel(group->wdog); CLR_MLD_SCHEDMSG(group->flags); CLR_MLD_WAITMSG(group->flags); net_unlock(); MLD_STATINCR(g_netstats.mld.leaves); /* Send a leave if the flag is set according to the state diagram */ if (IS_MLD_LASTREPORT(group->flags)) { ninfo("Schedule Leave Group message\n"); MLD_STATINCR(g_netstats.mld.done_sched); mld_waitmsg(group, ICMPV6_MCAST_LISTEN_DONE_V1); } /* Free the group structure */ mld_grpfree(dev, group); /* And remove the group address from the Ethernet drivers MAC filter set */ mld_removemcastmac(dev, mrec->ipv6mr_multiaddr.s6_addr16); return OK; } /* Return ENOENT if the address is not a member of the group */ ninfo("Return -ENOENT\n"); return -ENOENT; } #endif /* CONFIG_NET_MLD */