Ticket #11919: 0001-Fix-and-enable-ipv4-multicast.patch

src/add-ons/kernel/network/protocols/ipv4/ipv4.cpp

@@ -689 +689 @@
     if (module->deliver_data == NULL)
         return false;
 
-    // TODO: fix multicast!
-    return false;
     MutexLocker _(sMulticastGroupsLock);
 
+    if (buffer->interface_address == NULL) {
+        dprintf("%s: buffer->interface_address is NULL\n", __FUNCTION__);
+        return false;
+    }
+
     sockaddr_in* multicastAddr = (sockaddr_in*)buffer->destination;
 
     MulticastState::ValueIterator it = sMulticastState->Lookup(std::make_pair(
@@ -714 +717 @@
                 // as multicast filters are installed with an IPv4 protocol
                 // reference, we need to go and find the appropriate instance
                 // related to the 'receiving protocol' with module 'module'.
-                net_protocol* protocol = ipProtocol->socket->first_protocol;
+                protocol = ipProtocol->socket->first_protocol;
 
                 while (protocol != NULL && protocol->module != module)
                     protocol = protocol->next;
@@ -1612 +1615 @@
             notForUs = !wasMulticast;
     } else if (IN_MULTICAST(ntohl(header.destination))) {
         buffer->flags |= MSG_MCAST;
+
+        // Multicast MAC address is different from normal MAC
+        // Use sdl_index of Link level sockaddr structure to accquire
+        // reference
+        if (!sDatalinkModule->is_local_link_address(sDomain, false,
+                buffer->destination, &buffer->interface_address))
+            notForUs = true;
     } else {
         uint32 matchedAddressType = 0;
 

src/add-ons/kernel/network/stack/interfaces.cpp

@@ -1555 +1555 @@
 
             return interface->FirstForFamily(domain->family);
         }
+
+        // Multicast frame has different MAC address
+        // Just compare the index and name
+        if (linkAddress.sdl_index == interface->device->index
+            && memcmp(linkAddress.sdl_data, interface->device->name,
+                IF_NAMESIZE > linkAddress.sdl_nlen
+                ? linkAddress.sdl_nlen : IF_NAMESIZE) == 0) {
+            TRACE("  %s matches\n", interface->device->name);
+            // link address matches
+            if (unconfiguredOnly)
+                return interface->FirstUnconfiguredForFamily(domain->family);
+
+            return interface->FirstForFamily(domain->family);
+        }
     }
 
     return NULL;