Parsing html path from packet using Scapy

Question

I am making a application that resends the http packets using scapy.
When a packet is sniffed by scapy, it will check the source ip and destination path from header.
Then resend to place where it should go.

here is a example of header:

Url: 192.168.50.X:XXX/thePathInUrl

GET /thePathInUrl HTTP/1.1
Host: 192.168.50.250:448
Content-Type: text/plain
Content-Length: 12

this is body

I want to get the part of "/thePathInUrl"

I have researched a lot of solution about scapy.
Many of them are outdated and not work for the latest scapy or python3. Or mayby I just misunderstood the answers.

Here is some solutions I’ve tried before:

HTTP GET packet sniffer in Scapy

def http_header(packet):
        http_packet=str(packet)
        if http_packet.find('GET'):
                print GET_print(packet)

This one returned an empty [] to me.

SCAPY HTTP Request URL PCAP

http_layer= packet.getlayer('HTTPRequest').fields
ip_layer = packet.getlayer('IP').fields
print('n{0[src]} just  requested a {1[Method]} {1[Host]}{1[Path}]}'.format(ip_layer,http_layer))

This one said HTTPRequest is not existed in my packet

Also tried some answers using lambda expression. But several errors returned.

        print("catch packets")
        pkts=sniff(filter="port 448",count=1,)
    
        for xx in pkts:
            
            print(type(xx))

I also tried print what I sniffed

<class ‘scapy.layers.l2.Ether’>

This what It printed. It seems wrong? I was expecting a packet variable in side of list.
Or if there is other method is fit to such scenario?

Asked By: SODAIS

||

Source

Answer 1

Before picking scapy as solution. I used socket as parser.
But seems it did some job more than just receives packet for me.
So I decided to turn to scapy.
The critical mistake I’d made is that I forgot I have to start the connection myself.
When I finally used the wireshark diagnose the traffic, It looks like It’s just still at the phase of initiation on Three-way Handshake. There is no doubt why scapy returned nothing but empty.

I’ve not tried implementing Handshake code yet. I’ll update as I tested.
*edit: work well after tried.

Answered By: SODAIS

Parsing html path from packet using Scapy

Question:

Answers: