Trying to create a simple packet analyzer in gnuradio

GNU Radio
1

Hello,

I’m trying to make a packet analyzer with gnuradio which will translate
802.15.4 messages for me. I already have a gnuradio block that would
pass
my a raw data of the message from that start of frame. Right now the
messages are saved into a text file by connecting this block to a file
sink. I’m not sure how I read each message and analyze them. I don’t
know
much about programming in gnuradio/python. Can someone suggest me what
to
do?

Thank you very much,
Rithirong Thandee

2

On Fri, 16 Dec 2011 09:48:35 -0500, Fon, Rithirong Thandee wrote:

Hello,

I’m trying to make a packet analyzer with gnuradio
which will translate 802.15.4 messages for me. I already have a gnuradio
block that would pass my a raw data of the message from that start of
frame. Right now the messages are saved into a text file by connecting
this block to a file sink. I’m not sure how I read each message and
analyze them. I don’t know much about programming in gnuradio/python.
Can someone suggest me what to do?

Thank you very much,

Rithirong Thandee

In my opinion packet analysis isn’t the proper job of
Gnu Radio itself. What you can do is have your output file be a “FIFO”
file (named pipe), and then attach an external analysis program to that
FIFO, and write it in whatever you’re comfortable with.

3

You’ll have to somehow convert and decode the raw samples into data and
dump them as perhaps a PCAP file that can be analyzed in Wireshark.

More general question – would it make sense for GNU Radio to have
decoders than can dump to PCAP files? I noticed there are already TCP
and UDP sinks, for instance, but they’re not exactly the same things of
course.

Sean

From: discuss-gnuradio-bounces+sean.nowlan=removed_email_address@domain.invalid
[mailto:discuss-gnuradio-bounces+sean.nowlan=removed_email_address@domain.invalid] On
Behalf Of [email protected]
Sent: Friday, December 16, 2011 10:13 AM
To: [email protected]
Subject: Re: [Discuss-gnuradio] trying to create a simple packet
analyzer in gnuradio

On Fri, 16 Dec 2011 09:48:35 -0500, Fon, Rithirong Thandee wrote:

Hello,
I’m trying to make a packet analyzer with gnuradio which will translate
802.15.4 messages for me. I already have a gnuradio block that would
pass my a raw data of the message from that start of frame. Right now
the messages are saved into a text file by connecting this block to a
file sink. I’m not sure how I read each message and analyze them. I
don’t know much about programming in gnuradio/python. Can someone
suggest me what to do?
Thank you very much,
Rithirong Thandee

In my opinion packet analysis isn’t the proper job of Gnu Radio itself.
What you can do is have your output file be a “FIFO” file (named pipe),
and then attach an external analysis program to that FIFO, and write it
in whatever you’re comfortable with.

4

My end goal is to be able to re-transmitting the message to other
802.15.4
devices so I cannot dump it into a file. The decoder would be a simple
one.
Translation can easily be done by hand or even looking at the raw date
itself (source, destination, short message.) Let’s say if I have a block
that receive a message “hello,” all I need it the message header and
re-transmitting with “hello world” as a message.