From owner-freebsd-net  Fri Sep 21  2:25:14 2001
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Date: Fri, 21 Sep 2001 02:25:10 -0700 (PDT)
From: deepika kakrania <deepika_77@yahoo.com>
Subject: Re: IP multicasting...
To: freebsd-net@FreeBSD.ORG
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 Hi,

> 
> It's this line:
> 
> if (igmp->igmp_group.s_addr != 0 &&
>     !IN_MULTICAST(ntohl(igmp->igmp_group.s_addr))) {
>     ++igmpstat.igps_rcv_badqueries;
>     m_freem(m);
>     return;
> }
> 
> This test gets executed when it's a v2 query (mtu !=
> 0). The test stops
> further processing if the group address is NOT
> "0.0.0.0" or NOT a valid
> multicast address.
>

 I understand that above code gets excuted only if
query is Version 2 type. But above test is only for
Group-Specific query where igmp_group.s_addr != 0(it 
^^^^^^^^^^^^^^
contains the group address being reported to). In this
case we need to check whether given address is a valid
multicast addredd is or not.

 But where is the validity check being done when query
is Version 2 General query in which case
igmp_group.s_addr SHOULD BE Zero and ip_dst.s_addr
SHOULD be igmp_all_hosts_group.

 i.e., we need a validity check something like

  if (igmp->igmp_group.s_addr == 0 && 
      ip->ip_dst.s_addr != igmp_all_hosts_group)   {
                                                      
        ++igmpstat.igps_rcv_badqueries;
       m_freem(m);
       return;
  }

 Don't we need this for V2 GENERAL query?

Regards,
Deepika

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