PATCH for Multicast bug in RAW IP sockets 2.4.0

2001-03-02 Thread Mark Clayton


In ipv4 a call to the setsockopt() function with the optname set to 
IP_ADD_MEMBERSHIP and a raw ip socket adds the socket to the multicast 
group specified by the user. As a result the tcpip stack code does the 
following:
...
ip_setsockopt(_,_,IP_ADD_MEMBERSHIP,_,_) calls ip_mc_join_group(sock,_) 
function, which adds a multicast entry to the sock->protinfo.af_inet.mc_list 
and then adds a multicast entry to the bound device (if any) with a call 
to the ip_mc_inc_group() function.

When remote multicast packets that belong to the multicast group we just 
joined are received, the routing code recognizes the packets as multicast 
packet going to a local receiver, but the __raw_v4_lookup() function only 
examines the main sock address (sock->rcv_saddr) and totally forgets that 
this raw sock can a member of multiple multicast groups.

The following patch fixes the problem:

---[ PATCH STARTS ]

--- linux-2.4.2/net/ipv4/raw.c  Fri Feb  9 14:29:44 2001
+++ linux/net/ipv4/raw.cWed Feb 28 17:43:59 2001
@@ -54,6 +54,7 @@
 #include 
 #include 
 #include 
+#include 
 #include 
 #include 
 #include 
@@ -107,6 +108,18 @@
   !(s->rcv_saddr && s->rcv_saddr != laddr) &&
   !(s->bound_dev_if && s->bound_dev_if != dif))
break; /* gotcha */
+   if (LOCAL_MCAST(laddr)) {
+
+   struct ip_mc_socklist *iml;
+   struct ip_mreqn *imr;
+
+   for (iml=sk->protinfo.af_inet.mc_list; iml; iml=iml->next) {
+ imr = &(iml->multi);
+ if ((imr->imr_multiaddr.s_addr == laddr) && !(imr->imr_ifindex 
+&& imr->imr_ifindex != dif))
+   return s;
+   }
+
+   }
}
return s;
 }

---[ PATCH ENDS ]---

Note: the same problem exists for UDP sockets also.


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PATCH for Multicast bug in RAW IP sockets 2.4.0

2001-03-02 Thread Mark Clayton


In ipv4 a call to the setsockopt() function with the optname set to 
IP_ADD_MEMBERSHIP and a raw ip socket adds the socket to the multicast 
group specified by the user. As a result the tcpip stack code does the 
following:
...
ip_setsockopt(_,_,IP_ADD_MEMBERSHIP,_,_) calls ip_mc_join_group(sock,_) 
function, which adds a multicast entry to the sock-protinfo.af_inet.mc_list 
and then adds a multicast entry to the bound device (if any) with a call 
to the ip_mc_inc_group() function.

When remote multicast packets that belong to the multicast group we just 
joined are received, the routing code recognizes the packets as multicast 
packet going to a local receiver, but the __raw_v4_lookup() function only 
examines the main sock address (sock-rcv_saddr) and totally forgets that 
this raw sock can a member of multiple multicast groups.

The following patch fixes the problem:

---[ PATCH STARTS ]

--- linux-2.4.2/net/ipv4/raw.c  Fri Feb  9 14:29:44 2001
+++ linux/net/ipv4/raw.cWed Feb 28 17:43:59 2001
@@ -54,6 +54,7 @@
 #include linux/inet.h
 #include linux/netdevice.h
 #include linux/mroute.h
+#include linux/igmp.h
 #include net/ip.h
 #include net/protocol.h
 #include linux/skbuff.h
@@ -107,6 +108,18 @@
   !(s-rcv_saddr  s-rcv_saddr != laddr) 
   !(s-bound_dev_if  s-bound_dev_if != dif))
break; /* gotcha */
+   if (LOCAL_MCAST(laddr)) {
+
+   struct ip_mc_socklist *iml;
+   struct ip_mreqn *imr;
+
+   for (iml=sk-protinfo.af_inet.mc_list; iml; iml=iml-next) {
+ imr = (iml-multi);
+ if ((imr-imr_multiaddr.s_addr == laddr)  !(imr-imr_ifindex 
+ imr-imr_ifindex != dif))
+   return s;
+   }
+
+   }
}
return s;
 }

---[ PATCH ENDS ]---

Note: the same problem exists for UDP sockets also.


-
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the body of a message to [EMAIL PROTECTED]
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Please read the FAQ at  http://www.tux.org/lkml/