mitmproxy/libmproxy/proxy.py
2010-02-16 17:09:07 +13:00

375 lines
12 KiB
Python

"""
A simple proxy server implementation, which always reads all of a server
response into memory, performs some transformation, and then writes it back
to the client.
Development started from Neil Schemenauer's munchy.py
"""
import sys, os, time, string, socket, urlparse, re, select, copy
import SocketServer, ssl
import utils, controller
NAME = "mitmproxy"
config = None
class ProxyError(Exception):
def __init__(self, code, msg):
self.code, self.msg = code, msg
def __str__(self):
return "ProxyError(%s, %s)"%(self.code, self.msg)
class Config:
def __init__(self, pemfile):
self.pemfile = pemfile
def try_del(dict, key):
try:
del dict[key]
except KeyError:
pass
def parse_url(url):
"""
Returns a (scheme, host, port, path) tuple, or None on error.
"""
scheme, netloc, path, params, query, fragment = urlparse.urlparse(url)
if not scheme:
return None
if ':' in netloc:
host, port = string.split(netloc, ':')
port = int(port)
else:
host = netloc
port = 80
path = urlparse.urlunparse(('', '', path, params, query, fragment))
if not path:
path = "/"
return scheme, host, port, path
def parse_proxy_request(request):
"""
Parse a proxy request line. Return (method, scheme, host, port, path).
Raise ProxyError on error.
"""
try:
method, url, protocol = string.split(request)
except ValueError:
raise ProxyError(400, "Can't parse request")
if method in ['GET', 'HEAD', 'POST']:
if url.startswith("/"):
scheme, port, host, path = None, None, None, url
else:
parts = parse_url(url)
if not parts:
raise ProxyError(400, "Invalid url: %s"%url)
scheme, host, port, path = parts
elif method == 'CONNECT':
scheme = None
path = None
host, port = url.split(":")
port = int(port)
else:
raise ProxyError(501, "Unknown request method: %s" % method)
return method, scheme, host, port, path
class Request(controller.Msg):
FMT = '%s %s HTTP/1.0\r\n%s\r\n%s'
def __init__(self, connection, host, port, scheme, method, path, headers, content):
self.connection = connection
self.host, self.port, self.scheme = host, port, scheme
self.method, self.path, self.headers, self.content = method, path, headers, content
self.kill = False
controller.Msg.__init__(self)
def copy(self):
c = copy.copy(self)
c.headers = self.headers.copy()
return c
def url(self):
if (self.port, self.scheme) in [(80, "http"), (443, "https")]:
host = self.host
else:
host = "%s:%s"%(self.host, self.port)
return "%s://%s%s"%(self.scheme, host, self.path)
def set_url(self, url):
parts = parse_url(url)
if not parts:
return False
self.scheme, self.host, self.port, self.path = parts
return True
def is_response(self):
return False
def short(self):
return "%s %s"%(self.method, self.url())
def assemble(self):
"""
Assembles the request for transmission to the server. We make some
modifications to make sure interception works properly.
"""
headers = self.headers.copy()
try_del(headers, 'accept-encoding')
try_del(headers, 'proxy-connection')
try_del(headers, 'keep-alive')
try_del(headers, 'connection')
headers["connection"] = ["close"]
data = (self.method, self.path, str(headers), self.content)
return self.FMT%data
class Response(controller.Msg):
FMT = '%s\r\n%s\r\n%s'
def __init__(self, request, code, proto, msg, headers, content):
self.request = request
self.code, self.proto, self.msg = code, proto, msg
self.headers, self.content = headers, content
self.kill = False
controller.Msg.__init__(self)
def copy(self):
c = copy.copy(self)
c.headers = self.headers.copy()
return c
def is_response(self):
return True
def short(self):
return "%s %s"%(self.code, self.proto)
def assemble(self):
"""
Assembles the response for transmission to the client. We make some
modifications to make sure interception works properly.
"""
headers = self.headers.copy()
try_del(headers, 'accept-encoding')
try_del(headers, 'proxy-connection')
try_del(headers, 'connection')
try_del(headers, 'keep-alive')
headers["connection"] = ["close"]
proto = "%s %s %s"%(self.proto, self.code, self.msg)
data = (proto, str(headers), self.content)
return self.FMT%data
class BrowserConnection(controller.Msg):
def __init__(self, address, port):
self.address, self.port = address, port
controller.Msg.__init__(self)
def copy(self):
return copy.copy(self)
class Error(controller.Msg):
def __init__(self, connection, msg):
self.connection, self.msg = connection, msg
controller.Msg.__init__(self)
def copy(self):
return copy.copy(self)
class FileLike:
def __init__(self, o):
self.o = o
def __getattr__(self, attr):
return getattr(self.o, attr)
def flush(self):
pass
def readline(self):
result = ''
while True:
ch = self.read(1)
if not ch:
break
else:
result += ch
if ch == '\n':
break
return result
class ServerConnection:
def __init__(self, request):
self.request = request
self.server, self.rfile, self.wfile = None, None, None
self.connect()
self.send_request()
def connect(self):
try:
addr = socket.gethostbyname(self.request.host)
server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
if self.request.scheme == "https":
server = ssl.wrap_socket(server)
server.connect((addr, self.request.port))
except socket.error, err:
raise ProxyError(200, 'Error connecting to "%s": %s' % (self.request.host, err))
self.server = server
self.rfile, self.wfile = server.makefile('rb'), server.makefile('wb')
def send_request(self):
try:
self.wfile.write(self.request.assemble())
self.wfile.flush()
except socket.error, err:
raise ProxyError(500, 'Error sending data to "%s": %s' % (request.host, err))
def read_response(self):
proto = self.rfile.readline()
parts = proto.strip().split(" ", 2)
if not len(parts) == 3:
raise ProxyError(200, "Invalid server response.")
proto, code, msg = parts
code = int(code)
headers = utils.Headers()
headers.read(self.rfile)
if headers.has_key("content-length"):
content = self.rfile.read(int(headers["content-length"][0]))
else:
content = self.rfile.read()
return Response(self.request, code, proto, msg, headers, content)
def terminate(self):
try:
if not self.wfile.closed:
self.wfile.flush()
self.server.close()
except IOError:
pass
class ProxyHandler(SocketServer.StreamRequestHandler):
def __init__(self, request, client_address, server, q):
self.mqueue = q
SocketServer.StreamRequestHandler.__init__(self, request, client_address, server)
def handle(self):
server = None
bc = BrowserConnection(*self.client_address)
bc.send(self.mqueue)
try:
request = self.read_request(bc)
request = request.send(self.mqueue)
if request.kill:
self.finish()
return
server = ServerConnection(request)
response = server.read_response()
response = response.send(self.mqueue)
if response.kill:
server.terminate()
self.finish()
return
self.send_response(response)
except IOError:
pass
except ProxyError, e:
err = Error(bc, e.msg)
err.send(self.mqueue)
self.send_error(e.code, e.msg)
if server:
server.terminate()
self.finish()
def read_request(self, connection):
request = self.rfile.readline()
method, scheme, host, port, path = parse_proxy_request(request)
if not host:
raise ProxyError(200, 'Invalid request: %s'%request)
if method == "CONNECT":
# Discard additional headers sent to the proxy. Should I expose
# these to users?
while 1:
d = self.rfile.readline()
if not d.strip():
break
self.wfile.write('HTTP/1.1 200 Connection established\r\n')
self.wfile.write('Proxy-agent: %s\r\n'%NAME)
self.wfile.write('\r\n')
self.wfile.flush()
self.connection = ssl.wrap_socket(
self.connection,
certfile = config.pemfile,
keyfile = config.pemfile,
server_side = True,
ssl_version = ssl.PROTOCOL_SSLv23,
do_handshake_on_connect = False
)
self.rfile = FileLike(self.connection)
self.wfile = FileLike(self.connection)
method, _, _, _, path = parse_proxy_request(self.rfile.readline())
scheme = "https"
headers = utils.Headers()
headers.read(self.rfile)
if method == 'POST' and not headers.has_key('content-length'):
raise ProxyError(400, "Missing Content-Length for POST method")
if headers.has_key("content-length"):
content = self.rfile.read(int(headers["content-length"][0]))
else:
content = ""
return Request(connection, host, port, scheme, method, path, headers, content)
def send_response(self, response):
self.wfile.write(response.assemble())
self.wfile.flush()
def terminate(self, connection, wfile, rfile):
try:
if not getattr(wfile, "closed", False):
wfile.flush()
connection.close()
except IOError:
pass
def finish(self):
self.terminate(self.connection, self.wfile, self.rfile)
def send_error(self, code, body):
import BaseHTTPServer
response = BaseHTTPServer.BaseHTTPRequestHandler.responses[code][0]
self.wfile.write("HTTP/1.0 %s %s\r\n" % (code, response))
self.wfile.write("Server: %s\r\n"%NAME)
self.wfile.write("Content-type: text/html\r\n")
self.wfile.write("\r\n")
self.wfile.write('<html><head>\n<title>%d %s</title>\n</head>\n'
'<body>\n%s\n</body>\n</html>' % (code, response, body))
self.wfile.flush()
self.wfile.close()
self.rfile.close()
ServerBase = SocketServer.ThreadingTCPServer
class ProxyServer(ServerBase):
allow_reuse_address = True
def __init__(self, port):
self.port = port
ServerBase.__init__(self, ('', port), ProxyHandler)
self.masterq = None
def set_mqueue(self, q):
self.masterq = q
def process_request(self, request, client_address):
return ServerBase.process_request(self, request, client_address)
def finish_request(self, request, client_address):
self.RequestHandlerClass(request, client_address, self, self.masterq)