Ethernet Trailers

[a***@charter.net]

When I build an igmp message with

libnet_build_igmp
libnet_build_ipv4
libnet_build_ethernet

The packet is really smaller than the minimum ethernet frame (46 data bytes). If I try to add the trailer at the ethernet layer (so it is 64 bytes) it wipes out the packet, is it possible to have an offset in build_ethernet so the trailer is added after the IP datagram ?

[Mike Schiffman]

If required, the trailer should be added by your ethernet driver.

Post by a***@charter.net
When I build an igmp message with
libnet_build_igmp
libnet_build_ipv4
libnet_build_ethernet
The packet is really smaller than the minimum ethernet frame (46 data
bytes). If I try to add the trailer at the ethernet layer (so it is 64
bytes) it wipes out the packet, is it possible to have an offset in
build_ethernet so the trailer is added after the IP datagram ?

--
Mike Schiffman, CISSP
http://www.packetfactory.net/schiffman
Doveryay No Proveryay