Essayer de construire un proxy avec aiohttp

Question

J'essaye d'écrire un proxy HTTP de transfert avec aiohttp, je l'ai actuellement travaillé avec http mais je veux qu'il fonctionne avec https (sans déchiffrement).

import asyncio 
from aiohttp import web, ClientSession 

loop = asyncio.get_event_loop() 


async def handler(server_request): 
    if server_request.method == "CONNECT": 
     print(await server_request.read()) 
    else: 
     async with ClientSession() as session: 
      async with session.request(server_request.method, server_request.raw_path) as request: 
       response = web.StreamResponse(status=200, 
               reason='OK', 
               headers={'Content-Type': 'text/html'}) 
       await response.prepare(server_request) 
       while True: 
        chunk = await request.content.read() 
        if not chunk: 
         break 
        response.write(chunk) 
       return response 


server = web.Server(handler) 
loop.run_until_complete(loop.create_server(server, "0.0.0.0", 8080)) 
try: 

    loop.run_forever() 
except KeyboardInterrupt: 
    loop.close() 
    pass 

Je suis arrivé au point où je dois obtenir le corps raw pour envoyer le tunnel vers la destination mais ne peut pas sembler il

accès Si je tente de lire, je reçois un exception:

b'' 
Unhandled exception 
Traceback (most recent call last): 
    File "/usr/local/lib/python3.6/dist-packages/aiohttp/web_protocol.py", line 434, in start 
    yield from resp.prepare(request) 
AttributeError: 'NoneType' object has no attribute 'prepare' 

Answer 1

L'idée de base dans un proxy HTTPS est d'agir comme un proxy de flux, où l'on peut lire des données brutes et de mettre les données brutes à destination. Malheureusement, après avoir parcouru aiohttp je ne pouvais pas trouver quelque chose qui pourrait aider à atteindre la même chose, de sorte que vous avez besoin de nous Asyncio de base.

Ci-dessous des extraits de code montre la logique principale derrière la partie https

if head[0] == 'CONNECT': # https proxy 
    try: 
     logger.info('%sBYPASSING <%s %s> (SSL connection)' % 
      ('[%s] ' % ident if verbose >= 1 else '', head[0], head[1])) 
     m = REGEX_HOST.search(head[1]) 
     host = m.group(1) 
     port = int(m.group(2)) 
     req_reader, req_writer = yield from asyncio.open_connection(host, port, ssl=False, loop=loop) 
     client_writer.write(b'HTTP/1.1 200 Connection established\r\n\r\n') 
     @asyncio.coroutine 
     def relay_stream(reader, writer): 
      try: 
       while True: 
        line = yield from reader.read(1024) 
        if len(line) == 0: 
         break 
        writer.write(line) 
      except: 
       print_exc() 
     tasks = [ 
      asyncio.async(relay_stream(client_reader, req_writer), loop=loop), 
      asyncio.async(relay_stream(req_reader, client_writer), loop=loop), 
     ] 
     yield from asyncio.wait(tasks, loop=loop) 
    except: 
     print_exc() 
    finally: 
     return 

Le code complet PROXY est comme ci-dessous

#!/usr/bin/env python3 

VERSION = "v0.2.0" 

""" 
Copyright (c) 2013 devunt 

Permission is hereby granted, free of charge, to any person 
obtaining a copy of this software and associated documentation 
files (the "Software"), to deal in the Software without 
restriction, including without limitation the rights to use, 
copy, modify, merge, publish, distribute, sublicense, and/or sell 
copies of the Software, and to permit persons to whom the 
Software is furnished to do so, subject to the following 
conditions: 

The above copyright notice and this permission notice shall be 
included in all copies or substantial portions of the Software. 

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES 
OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT 
HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, 
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 
OTHER DEALINGS IN THE SOFTWARE. 
""" 

import sys 
if sys.version_info < (3, 4): 
    print('Error: You need python 3.4.0 or above.') 
    exit(1) 

from argparse import ArgumentParser 
from socket import TCP_NODELAY 
from time import time 
from traceback import print_exc 
import asyncio 
import logging 
import random 
import functools 
import re 


REGEX_HOST   = re.compile(r'(.+?):([0-9]{1,5})') 
REGEX_CONTENT_LENGTH = re.compile(r'\r\nContent-Length: ([0-9]+)\r\n', re.IGNORECASE) 
REGEX_CONNECTION  = re.compile(r'\r\nConnection: (.+)\r\n', re.IGNORECASE) 

clients = {} 

logging.basicConfig(level=logging.INFO, format='[%(asctime)s] {%(levelname)s} %(message)s') 
logging.getLogger('asyncio').setLevel(logging.CRITICAL) 
logger = logging.getLogger('warp') 
verbose = 0 


def accept_client(client_reader, client_writer, *, loop=None): 
    ident = hex(id(client_reader))[-6:] 
    task = asyncio.async(process_warp(client_reader, client_writer, loop=loop), loop=loop) 
    clients[task] = (client_reader, client_writer) 
    started_time = time() 

    def client_done(task): 
     del clients[task] 
     client_writer.close() 
     logger.debug('[%s] Connection closed (took %.5f seconds)' % (ident, time() - started_time)) 

    logger.debug('[%s] Connection started' % ident) 
    task.add_done_callback(client_done) 


@asyncio.coroutine 
def process_warp(client_reader, client_writer, *, loop=None): 
    ident = str(hex(id(client_reader)))[-6:] 
    header = '' 
    payload = b'' 
    try: 
     RECV_MAX_RETRY = 3 
     recvRetry = 0 
     while True: 
      line = yield from client_reader.readline() 
      if not line: 
       if len(header) == 0 and recvRetry < RECV_MAX_RETRY: 
        # handle the case when the client make connection but sending data is delayed for some reasons 
        recvRetry += 1 
        yield from asyncio.sleep(0.2, loop=loop) 
        continue 
       else: 
        break 
      if line == b'\r\n': 
       break 
      if line != b'': 
       header += line.decode() 

     m = REGEX_CONTENT_LENGTH.search(header) 
     if m: 
      cl = int(m.group(1)) 
      while (len(payload) < cl): 
       payload += yield from client_reader.read(1024) 
    except: 
     print_exc() 

    if len(header) == 0: 
     logger.debug('[%s] !!! Task reject (empty request)' % ident) 
     return 

    req = header.split('\r\n')[:-1] 
    if len(req) < 4: 
     logger.debug('[%s] !!! Task reject (invalid request)' % ident) 
     return 
    head = req[0].split(' ') 
    if head[0] == 'CONNECT': # https proxy 
     try: 
      logger.info('%sBYPASSING <%s %s> (SSL connection)' % 
       ('[%s] ' % ident if verbose >= 1 else '', head[0], head[1])) 
      m = REGEX_HOST.search(head[1]) 
      host = m.group(1) 
      port = int(m.group(2)) 
      req_reader, req_writer = yield from asyncio.open_connection(host, port, ssl=False, loop=loop) 
      client_writer.write(b'HTTP/1.1 200 Connection established\r\n\r\n') 
      @asyncio.coroutine 
      def relay_stream(reader, writer): 
       try: 
        while True: 
         line = yield from reader.read(1024) 
         if len(line) == 0: 
          break 
         writer.write(line) 
       except: 
        print_exc() 
      tasks = [ 
       asyncio.async(relay_stream(client_reader, req_writer), loop=loop), 
       asyncio.async(relay_stream(req_reader, client_writer), loop=loop), 
      ] 
      yield from asyncio.wait(tasks, loop=loop) 
     except: 
      print_exc() 
     finally: 
      return 
    phost = False 
    sreq = [] 
    sreqHeaderEndIndex = 0 
    for line in req[1:]: 
     headerNameAndValue = line.split(': ', 1) 
     if len(headerNameAndValue) == 2: 
      headerName, headerValue = headerNameAndValue 
     else: 
      headerName, headerValue = headerNameAndValue[0], None 

     if headerName.lower() == "host": 
      phost = headerValue 
     elif headerName.lower() == "connection": 
      if headerValue.lower() in ('keep-alive', 'persist'): 
       # current version of this program does not support the HTTP keep-alive feature 
       sreq.append("Connection: close") 
      else: 
       sreq.append(line) 
     elif headerName.lower() != 'proxy-connection': 
      sreq.append(line) 
      if len(line) == 0 and sreqHeaderEndIndex == 0: 
       sreqHeaderEndIndex = len(sreq) - 1 
    if sreqHeaderEndIndex == 0: 
     sreqHeaderEndIndex = len(sreq) 

    m = REGEX_CONNECTION.search(header) 
    if not m: 
     sreq.insert(sreqHeaderEndIndex, "Connection: close") 

    if not phost: 
     phost = '127.0.0.1' 
    path = head[1][len(phost)+7:] 

    logger.info('%sWARPING <%s %s>' % ('[%s] ' % ident if verbose >= 1 else '', head[0], head[1])) 

    new_head = ' '.join([head[0], path, head[2]]) 

    m = REGEX_HOST.search(phost) 
    if m: 
     host = m.group(1) 
     port = int(m.group(2)) 
    else: 
     host = phost 
     port = 80 

    try: 
     req_reader, req_writer = yield from asyncio.open_connection(host, port, flags=TCP_NODELAY, loop=loop) 
     req_writer.write(('%s\r\n' % new_head).encode()) 
     yield from req_writer.drain() 
     yield from asyncio.sleep(0.2, loop=loop) 

     def generate_dummyheaders(): 
      def generate_rndstrs(strings, length): 
       return ''.join(random.choice(strings) for _ in range(length)) 
      import string 
      return ['X-%s: %s\r\n' % (generate_rndstrs(string.ascii_uppercase, 16), 
       generate_rndstrs(string.ascii_letters + string.digits, 128)) for _ in range(32)] 

     req_writer.writelines(list(map(lambda x: x.encode(), generate_dummyheaders()))) 
     yield from req_writer.drain() 

     req_writer.write(b'Host: ') 
     yield from req_writer.drain() 
     def feed_phost(phost): 
      i = 1 
      while phost: 
       yield random.randrange(2, 4), phost[:i] 
       phost = phost[i:] 
       i = random.randrange(2, 5) 
     for delay, c in feed_phost(phost): 
      yield from asyncio.sleep(delay/10.0, loop=loop) 
      req_writer.write(c.encode()) 
      yield from req_writer.drain() 
     req_writer.write(b'\r\n') 
     req_writer.writelines(list(map(lambda x: (x + '\r\n').encode(), sreq))) 
     req_writer.write(b'\r\n') 
     if payload != b'': 
      req_writer.write(payload) 
      req_writer.write(b'\r\n') 
     yield from req_writer.drain() 

     try: 
      while True: 
       buf = yield from req_reader.read(1024) 
       if len(buf) == 0: 
        break 
       client_writer.write(buf) 
     except: 
      print_exc() 

    except: 
     print_exc() 

    client_writer.close() 


@asyncio.coroutine 
def start_warp_server(host, port, *, loop = None): 
    try: 
     accept = functools.partial(accept_client, loop=loop) 
     server = yield from asyncio.start_server(accept, host=host, port=port, loop=loop) 
    except OSError as ex: 
     logger.critical('!!! Failed to bind server at [%s:%d]: %s' % (host, port, ex.args[1])) 
     raise 
    else: 
     logger.info('Server bound at [%s:%d].' % (host, port)) 
     return server 


def main(): 
    """CLI frontend function. It takes command line options e.g. host, 
    port and provides `--help` message. 

    """ 
    parser = ArgumentParser(description='Simple HTTP transparent proxy') 
    parser.add_argument('-H', '--host', default='127.0.0.1', 
         help='Host to listen [default: %(default)s]') 
    parser.add_argument('-p', '--port', type=int, default=8800, 
         help='Port to listen [default: %(default)d]') 
    parser.add_argument('-v', '--verbose', action='count', default=0, 
         help='Print verbose') 
    args = parser.parse_args() 
    if not (1 <= args.port <= 65535): 
     parser.error('port must be 1-65535') 
    if args.verbose >= 3: 
     parser.error('verbose level must be 1-2') 
    if args.verbose >= 1: 
     logger.setLevel(logging.DEBUG) 
    if args.verbose >= 2: 
     logging.getLogger('warp').setLevel(logging.DEBUG) 
     logging.getLogger('asyncio').setLevel(logging.DEBUG) 
    global verbose 
    verbose = args.verbose 
    loop = asyncio.get_event_loop() 
    try: 
     loop.run_until_complete(start_warp_server(args.host, args.port)) 
     loop.run_forever() 
    except OSError: 
     pass 
    except KeyboardInterrupt: 
     print('bye') 
    finally: 
     loop.close() 


if __name__ == '__main__': 
    exit(main()) 

PS: Le code a été pris de https://github.com/devunt/warp. Le code complet est posté ici afin que si le lien devient invalide à l'avenir, la réponse est toujours valide.