Don't reply to DHCPv6 SOLICIT messages when not configured for statefull DHCPv6.

src/rfc3315.c

@@ -824,6 +824,19 @@ static int dhcp6_no_relay(struct state *state, int msg_type, void *inbuff, size_
 	  }
 	else
 	  { 
+	    /* Windows 8 always requests an address even if the Managed bit
+	       in RA is 0 and it keeps retrying if it receives a reply
+	       stating that no addresses are available. We solve this 
+	       by not replying at all if we're not configured to give any 
+	       addresses by DHCPv6. RFC 3315 17.2.1. appears to allow this. */
+	    
+	    for (c = state->context; c; c = c->current)
+	      if (!(c->flags & CONTEXT_RA_STATELESS))
+		break;
+	    
+	    if (!c)
+	      return 0;
+	    
 	    /* no address, return error */
 	    o1 = new_opt6(OPTION6_STATUS_CODE);
 	    put_opt6_short(DHCP6NOADDRS);