Take the 2-minute tour ×
Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Using the minimal Fedora 14 distribution provided in PlanetLab, I'm forging packets through Scapy and sending them with tcpreplay.

I thought I had installed all the necessary packages to run scapy and tcpreplay, but for some reason scapy can't access the mac address of the machine.

For instance, if I send a packet through Scapy, I always get:

"WARNING: Mac address to reach destination not found. Using broadcast."

Also, if I add an Ethernet layer to an existing IP packet, the resulting destination is always ff:ff:ff:ff:ff:ff.

What am I missing here?

share|improve this question

migrated from stackoverflow.com Mar 27 '13 at 13:35

This question came from our site for professional and enthusiast programmers.

1 Answer 1

up vote 1 down vote accepted

Ok, so I figured out what was happening:

  • On PlanetLab you can't make any ARP requests, even if you are root. You can only read the ARP table that is provided to you
  • When Scapy builds an Ethernet layer with no input destination address, it makes an ARP request to fill out that field of the Ethernet header.

=> Solution: I had to lookup the ARP table myself and specify the gateway's MAC address in each packet.

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.