JJW@SU-AI.ARPA (Joe Weening) (05/21/86)
What do the ICMP redirects that are used to fool Unix contain in the field that is supposed to be the Internet header of the original datagram causing a redirect? Can you just make up some values to cause the action that you desire? It would seem that hosts should do some validity checking on redirects before believing them. This should include checking the Internet header field to see if it corresponds to a packet that was sent out. It would also be useful to see if the gateway sending a redirect is in fact the one to which the original message was sent, and ignore it if not. But this is complicated by the fact that it is apparently legal for a gateway to use any of its addresses as the IP source address of the redirect.