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Receive and Print a Twilio SMS with Python

For clarification, I don't want to reply to the SMS. Every tutorial or document I've looked at is about setting up a port to listen on.
What I'm trying to do is just get the SMS and print it. I can send them fine and without problems.
Here is my sending function, and it works.
def send():
message = client.messages \
.create(
body=sendMSG,
from_='MY_TWILIO_NUMBER',
to='MY_PERSONAL_NUMBER'
)
print(message.sid)
How would you receive an SMS without Flask? Is there a way to do something similar to this method below just for receiving?
def receive():
message = client.messages \
.recieve(
from_='MY_PERSONAL_NUMBER',
to='MY_TWILIO_NUMBER'
)
print(message.sid)

I have not personally tried to get SMS messages from the logs before, always getting it directly through a webhook, but from what I see, it appears the command you might be looking for is list(). You can add filters, as shown in the API docs, and there are three filtering options. You can filter by DateSent, To, or From.
I have not tried this, but it would seem that the way to use this would be the following (adjusted from the code they supply):
# Download the helper library from https://www.twilio.com/docs/python/install
from twilio.rest import Client
# Your Account Sid and Auth Token from twilio.com/console
account_sid = 'ACXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX'
auth_token = 'your_auth_token'
client = Client(account_sid, auth_token)
messages = client.messages.list(from='MY_PERSONAL_NUMBER', to='MY_TWILIO_NUMBER')
for record in messages:
print(record.sid)
If that doesn't work, the variables they use are actually capitalized "To" and "From", so you might try that.
After looking at that a bit, you might be looking more for this:
received = client.messages.list(to='MY_TWILIO_NUMBER')
sent = client.messages.list(from='MY_PERSONAL_NUMBER')
That will separate out those sent to you, and those sent from you

Scapy: How to manipulate Host in http header?

I wrote this piece of code to get http header and set Host:
http_layer = packet.getlayer(http.HTTPRequest).fields
http_layer['Host'] = "newHostName"
return packet
After running the afforementioned code,the new host name has been set correctly, but the problem is that when I write the packet in pcap file, I still see the previous host in http fields,
Is there an absolute way to manipulate http_layer['Host'] ?
Any help would be appreciated.
Regards.

After all, found the answer.
The key is that scapy firstly parses HTTP Request and shows the dict of its fields. So when we try to assign a new field like Host, it changes the Host which it has already parsed and does not change the original field value.
So, this is the way to modify Host or any other respective fields:
str_headers = pkt['HTTP']['HTTP Request'].fields['Headers']
str_headers = str_headers.replace('Host: ' + pkt['HTTP']['HTTP Request'].fields['Host'], 'Host: ' + new_val)
pkt['HTTP']['HTTP Request'].fields['Headers'] = str_headers
return pkt

Telnet send command and then read response

This shouldn't be that complicated, but it seems that both the Ruby and Python Telnet libs have awkward APIs. Can anyone show me how to write a command to a Telnet host and then read the response into a string for some processing?
In my case "SEND" with a newline retrieves some temperature data on a device.
With Python I tried:
tn.write(b"SEND" + b"\r")
str = tn.read_eager()
which returns nothing.
In Ruby I tried:
tn.puts("SEND")
which should return something as well, the only thing I've gotten to work is:
tn.cmd("SEND") { |c| print c }
which you can't do much with c.
Am I missing something here? I was expecting something like the Socket library in Ruby with some code like:
s = TCPSocket.new 'localhost', 2000
while line = s.gets # Read lines from socket
puts line # and print them
end

I found out that if you don't supply a block to the cmd method, it will give you back the response (assuming the telnet is not asking you for anything else). You can send the commands all at once (but get all of the responses bundled together) or do multiple calls, but you would have to do nested block callbacks (I was not able to do it otherwise).
require 'net/telnet'
class Client
# Fetch weather forecast for NYC.
#
# #return [String]
def response
fetch_all_in_one_response
# fetch_multiple_responses
ensure
disconnect
end
private
# Do all the commands at once and return everything on one go.
#
# #return [String]
def fetch_all_in_one_response
client.cmd("\nNYC\nX\n")
end
# Do multiple calls to retrieve the final forecast.
#
# #return [String]
def fetch_multiple_responses
client.cmd("\r") do
client.cmd("NYC\r") do
client.cmd("X\r") do |forecast|
return forecast
end
end
end
end
# Connect to remote server.
#
# #return [Net::Telnet]
def client
#client ||= Net::Telnet.new(
'Host' => 'rainmaker.wunderground.com',
'Timeout' => false,
'Output_log' => File.open('output.log', 'w')
)
end
# Close connection to the remote server.
def disconnect
client.close
end
end
forecast = Client.new.response
puts forecast

Decode HTTP packet content in python as seen in wireshark

Ok, so bascially what I want to do is intercept some packets that I know contains some JSON data. But HTTP packets aren't human-readable, so that's my problem, I need to make the entire packet (not just the header, which is already plain text), human-readable. I have no experience with networking at all.
import pcap
from impacket import ImpactDecoder, ImpactPacket
def print_packet(pktlen, data, timestamp):
if not data:
return
decoder = ImpactDecoder.EthDecoder()
ether = decoder.decode(data)
iphdr = ether.child()
tcphdr = iphdr.child()
if iphdr.get_ip_src() == '*******':
print tcphdr
p = pcap.pcapObject()
dev = 'wlan0'
p.open_live(dev, 1600, 0, 100)
try:
p.setfilter('tcp', 0, 0)
while 1:
p.loop(1, print_packet)
except KeyboardInterrupt:
print 'shutting down'
I've found tools like libpcap-python, scapy, Impacket pcapy and so on. They all seem good, but I can't figure out how to decode the packets properly with them.
Wireshark has this thing called "Line-based text data: text/html" which basically displays the information I'm after, so I thought it would be trivial to get the same info with python, it turns out it was not.

Both HTTP and JSON are human readable. On Wireshark, select a packet that relates to your HTTP transaction and right-click, select Follow TCP Stream, which should display the transaction in a Human readable form.

Using python sockets to receive large http requests

I am using python sockets to receive web style and soap requests. The code I have is
import socket
svrsocket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
host = socket.gethostname();
svrsocket.bind((host,8091))
svrsocket.listen(1)
clientSocket, clientAddress = svrsocket.accept()
message = clientSocket.recv(4096)
Some of the soap requests I receive, however, are huge. 650k huge, and this could become several Mb. Instead of the single recv I tried
message = ''
while True:
data = clientSocket.recv(4096)
if len(data) == 0:
break;
message = message + data
but I never receive a 0 byte data chunk with firefox or safari, although the python socket how to says I should.
What can I do to get round this?

Unfortunately you can't solve this on the TCP level - HTTP defines its own connection management, see RFC 2616. This basically means you need to parse the stream (at least the headers) to figure out when a connection could be closed.
See related questions here - https://stackoverflow.com/search?q=http+connection

Hiya
Firstly I want to reinforce what the previous answer said
Unfortunately you can't solve this on the TCP level
Which is true, you can't. However you can implement an http parser on top of your tcp sockets. And that's what I want to explore here.
Let's get started
Problem and Desired Outcome
Right now we are struggling to find the end to a datastream. We expected our stream to end with a fixed ending but now we know that HTTP does not define any message suffix
And yet, we move forward.
There is one question we can now ask, "Can we ever know the length of the message in advance?" and the answer to that is YES! Sometimes...
You see HTTP/1.1 defines a header called Content-Length and as you'd expect it has exactly what we want, the content length; but there is something else in the shadows: Transfer-Encoding: chunked. unless you really want to learn about it, we'll stay away from it for now.
Solution
Here is a solution. You're not gonna know what some of these functions are at first, but if you stick with me, I'll explain. Alright... Take a deep breath.
Assuming conn is a socket connection to the desired HTTP server
...
rawheaders = recvheaders(conn,end=CRLF)
headers = dict_headers(io.StringIO(rawheaders))
l_content = headers['Content-Length']
#okay. we've got content length by magic
buffersize = 4096
while True:
if l_content <= 0: break
data = clientSocket.recv(buffersize)
message += data
l_content -= len(data)
...
As you can see, we enter the loop already knowing the Content-Length as l_content
While we iterate we keep track of the remaining content by subtracting the length of clientSocket.recv(buff) from l_content.
When we've read at least as much data as l_content, we are done
if l_content <= 0: break
Frustration
Note: For some these next bits I'm gonna give psuedo code because the code can be a bit dense
So now you're asking, what is rawheaders = recvheaders(conn), what is headers = dict_headers(io.StringIO(rawheaders)),
and HOW did we get headers['Content-Length']?!
For starters, recvheaders. The HTTP/1.1 spec doesn't define a message suffix, but it does define something useful: a suffix for the http headers! And that suffix is CRLF aka \r\n.That means we know when we've recieved the headers when we read CRLF. So we can write a function like
def recvheaders(sock):
rawheaders = ''
until we read crlf:
rawheaders = sock.recv()
return rawheaders
Next, parsing the headers.
def dict_header(ioheaders:io.StringIO):
"""
parses an http response into the status-line and headers
"""
#here I expect ioheaders to be io.StringIO
#the status line is always the first line
status = ioheaders.readline().strip()
headers = {}
for line in ioheaders:
item = line.strip()
if not item:
break
//headers look like this
//'Header-Name' : 'Value'
item = item.split(':', 1)
if len(item) == 2:
key, value = item
headers[key] = value
return status, headers
Here we read the status line then we continue to iterate over every remaining line
and build [key,value] pairs from Header: Value with
item = line.strip()
item = item.split(':', 1)
# We do split(':',1) to avoid cases like
# 'Header' : 'foo:bar' -> ['Header','foo','bar']
# when we want ---------> ['Header','foo:bar']
then we take that list and add it to the headers dict
#unpacking
#key = item[0], value = item[1]
key, value = item
header[key] = value
BAM, we've created a map of headers
From there headers['Content-Length'] falls right out.
So,
This structure will work as long as you can guarantee that you will always recieve Content-Length
If you've made it this far WOW, thanks for taking the time and I hope this helped you out!
TLDR; if you want to know the length of an http message with sockets, write an http parser