I would like to know if there is any possibility to live capture network packets and save it to a variable for example in python. I need some information to get from it and not to save it to a file.
I need to capture http packets and get source addres and its content, which should be a html code, to extract only text from it and then do the rest of the job on that information. There is no reason to save every packet to a file because whole process would be more slower. I was looking for quite a long time for any tool to do this but no success. Please, if you know any tool that could help me to do this, write about it.
I'm sure you have seen this link about a library to process PCAP files. Now the question is how to acquire in real time without storing in a file.
Probably easiest is to use a fifo
$ mkfifo /tmp/tcpdump.fifo
Now you can capture and feed data into the named fifo
$ sudo tcpdump -s0 -i eth0 -f /tmp/tcpdump.fifo tcp port 80
And in your python program you can open '/tmp/tcpdump.fifo' as the input file as per the instructions in the link.
Alternatively you can try opening '/dev/stdin' in your program and reading the data from there; you could then pipe the PCAP data straight into stdin using the shell and skipping the intermediate named fifo.
$ sudo tcpdump -s0 -i eth0 -f - tcp port 80 | ./youprogram.py