python - How to create HTTP GET request Scapy?

Question

I need to create HTTP GET request and save the data response. I tried to use this:

    syn = IP(dst=URL) / TCP(dport=80, flags='S')
    syn_ack = sr1(syn)
    getStr = 'GET / HTTP/1.1
Host: www.google.com

'
    request = IP(dst='www.google.com') / TCP(dport=80, sport=syn_ack[TCP].dport,
            seq=syn_ack[TCP].ack, ack=syn_ack[TCP].seq + 1, flags='A') / getStr
    reply = sr1(request)
    print reply.show()

But when I print reply I don't see any data response. In addition, when I checked in 'Wireshark' I got SYN, SYN/ACK but I didn't get an ACK.

Image:

Edit:

I try to do that now:

# Import scapy
from scapy.all import *

# Print info header
print "[*] ACK-GET example -- Thijs 'Thice' Bosschert, 06-06-2011"

# Prepare GET statement
get='GET / HTTP/1.0

'

# Set up target IP
ip=IP(dst="www.google.com")

# Generate random source port number
port=RandNum(1024,65535)

# Create SYN packet
SYN=ip/TCP(sport=port, dport=80, flags="S", seq=42)

# Send SYN and receive SYN,ACK
print "
[*] Sending SYN packet"
SYNACK=sr1(SYN)

# Create ACK with GET request
ACK=ip/TCP(sport=SYNACK.dport, dport=80, flags="A", seq=SYNACK.ack, ack=SYNACK.seq + 1) / get

# SEND our ACK-GET request
print "
[*] Sending ACK-GET packet"
reply,error=sr(ACK)

# print reply from server
print "
[*] Reply from server:"
print reply.show()

print '
[*] Done!'

but its print me in reply from server;

0000 IP / TCP 192.168.44.130:23181 > 216.58.208.164:http A / Raw ==> IP / TCP 216.58.208.164:http > 192.168.44.130:23181 A / Padding None

And I need Line-based text data: text/html.

Answer 1

You are sending a RST segment in response to the SYN-ACK because your kernel has no knowledge of the SYN you sent via Scapy (see here). This could be solved with an iptable rule:

iptables -A OUTPUT -p tcp --tcp-flags RST RST -s <your ip> -j DROP

Because you are ending the connection with that RST segment, when you send your HTTP request, the endpoint answers with a RST too because connection is not established and so you are using show() on a RST segment with no data, that is why you do not see anything.