mitmproxy/libmproxy/proxy.py

585 lines
21 KiB
Python

import os, socket, time, threading, copy
from OpenSSL import SSL
from netlib import tcp, http, certutils, http_auth
import utils, version, platform, controller, stateobject
TRANSPARENT_SSL_PORTS = [443, 8443]
class AddressPriority(object):
"""
Enum that signifies the priority of the given address when choosing the destination host.
Higher is better (None < i)
"""
FORCE = 5
"""forward mode"""
MANUALLY_CHANGED = 4
"""user changed the target address in the ui"""
FROM_SETTINGS = 3
"""reverse proxy mode"""
FROM_CONNECTION = 2
"""derived from transparent resolver"""
FROM_PROTOCOL = 1
"""derived from protocol (e.g. absolute-form http requests)"""
class ProxyError(Exception):
def __init__(self, code, msg, headers=None):
self.code, self.msg, self.headers = code, msg, headers
def __str__(self):
return "ProxyError(%s, %s)" % (self.code, self.msg)
class Log:
def __init__(self, msg):
self.msg = msg
class ProxyConfig:
def __init__(self, certfile=None, cacert=None, clientcerts=None, no_upstream_cert=False, body_size_limit=None,
reverse_proxy=None, forward_proxy=None, transparent_proxy=None, authenticator=None):
self.certfile = certfile
self.cacert = cacert
self.clientcerts = clientcerts
self.no_upstream_cert = no_upstream_cert
self.body_size_limit = body_size_limit
self.reverse_proxy = reverse_proxy
self.forward_proxy = forward_proxy
self.transparent_proxy = transparent_proxy
self.authenticator = authenticator
self.certstore = certutils.CertStore()
class ClientConnection(tcp.BaseHandler, stateobject.SimpleStateObject):
def __init__(self, client_connection, address, server):
if client_connection: # Eventually, this object is restored from state. We don't have a connection then.
tcp.BaseHandler.__init__(self, client_connection, address, server)
else:
self.connection = None
self.server = None
self.wfile = None
self.rfile = None
self.address = None
self.clientcert = None
self.timestamp_start = utils.timestamp()
self.timestamp_end = None
self.timestamp_ssl_setup = None
_stateobject_attributes = dict(
timestamp_start=float,
timestamp_end=float,
timestamp_ssl_setup=float
)
def _get_state(self):
d = super(ClientConnection, self)._get_state()
d.update(
address={"address": self.address(), "use_ipv6": self.address.use_ipv6},
clientcert=self.cert.to_pem() if self.clientcert else None
)
return d
def _load_state(self, state):
super(ClientConnection, self)._load_state(state)
self.address = tcp.Address(**state["address"]) if state["address"] else None
self.clientcert = certutils.SSLCert.from_pem(state["clientcert"]) if state["clientcert"] else None
def copy(self):
return copy.copy(self)
@classmethod
def _from_state(cls, state):
f = cls(None, tuple(), None)
f._load_state(state)
return f
def convert_to_ssl(self, *args, **kwargs):
tcp.BaseHandler.convert_to_ssl(self, *args, **kwargs)
self.timestamp_ssl_setup = utils.timestamp()
def finish(self):
tcp.BaseHandler.finish(self)
self.timestamp_end = utils.timestamp()
class ServerConnection(tcp.TCPClient, stateobject.SimpleStateObject):
def __init__(self, address, priority):
tcp.TCPClient.__init__(self, address)
self.priority = priority
self.peername = None
self.timestamp_start = None
self.timestamp_end = None
self.timestamp_tcp_setup = None
self.timestamp_ssl_setup = None
_stateobject_attributes = dict(
peername=tuple,
timestamp_start=float,
timestamp_end=float,
timestamp_tcp_setup=float,
timestamp_ssl_setup=float,
address=tcp.Address,
source_address=tcp.Address,
cert=certutils.SSLCert,
ssl_established=bool,
sni=str
)
def _get_state(self):
d = super(ServerConnection, self)._get_state()
d.update(
address={"address": self.address(), "use_ipv6": self.address.use_ipv6},
source_address= {"address": self.source_address(),
"use_ipv6": self.source_address.use_ipv6} if self.source_address else None,
cert=self.cert.to_pem() if self.cert else None
)
return d
def _load_state(self, state):
super(ServerConnection, self)._load_state(state)
self.address = tcp.Address(**state["address"]) if state["address"] else None
self.source_address = tcp.Address(**state["source_address"]) if state["source_address"] else None
self.cert = certutils.SSLCert.from_pem(state["cert"]) if state["cert"] else None
@classmethod
def _from_state(cls, state):
f = cls(tuple(), None)
f._load_state(state)
return f
def copy(self):
return copy.copy(self)
def connect(self):
self.timestamp_start = utils.timestamp()
tcp.TCPClient.connect(self)
self.peername = self.connection.getpeername()
self.timestamp_tcp_setup = utils.timestamp()
def send(self, message):
self.wfile.write(message)
self.wfile.flush()
def establish_ssl(self, clientcerts, sni):
clientcert = None
if clientcerts:
path = os.path.join(clientcerts, self.address.host.encode("idna")) + ".pem"
if os.path.exists(path):
clientcert = path
try:
self.convert_to_ssl(cert=clientcert, sni=sni)
self.timestamp_ssl_setup = utils.timestamp()
except tcp.NetLibError, v:
raise ProxyError(400, str(v))
def finish(self):
tcp.TCPClient.finish(self)
self.timestamp_end = utils.timestamp()
from . import protocol
from .protocol.http import HTTPResponse
class RequestReplayThread(threading.Thread):
def __init__(self, config, flow, masterq):
self.config, self.flow, self.channel = config, flow, controller.Channel(masterq)
threading.Thread.__init__(self)
def run(self):
try:
r = self.flow.request
server = ServerConnection(self.flow.server_conn.address(), None)
server.connect()
if self.flow.server_conn.ssl_established:
server.establish_ssl(self.config.clientcerts,
self.flow.server_conn.sni)
server.send(r._assemble())
self.flow.response = HTTPResponse.from_stream(server.rfile, r.method, body_size_limit=self.config.body_size_limit)
self.channel.ask("response", self.flow.response)
except (ProxyError, http.HttpError, tcp.NetLibError), v:
self.flow.error = protocol.primitives.Error(str(v))
self.channel.ask("error", self.flow.error)
class ConnectionHandler:
def __init__(self, config, client_connection, client_address, server, channel, server_version):
self.config = config
self.client_conn = ClientConnection(client_connection, client_address, server)
self.server_conn = None
self.channel, self.server_version = channel, server_version
self.close = False
self.conntype = None
self.sni = None
self.server_address_priority = None
self.mode = "regular"
if self.config.reverse_proxy:
self.mode = "reverse"
if self.config.transparent_proxy:
self.mode = "transparent"
def handle(self):
self.log("clientconnect")
self.channel.ask("clientconnect", self)
self.determine_conntype()
try:
try:
# Can we already identify the target server and connect to it?
server_address = None
address_priority = None
if self.config.forward_proxy:
server_address = self.config.forward_proxy[1:]
address_priority = AddressPriority.FORCE
elif self.config.reverse_proxy:
server_address = self.config.reverse_proxy[1:]
address_priority = AddressPriority.FROM_SETTINGS
elif self.config.transparent_proxy:
server_address = self.config.transparent_proxy["resolver"].original_addr(
self.client_conn.connection)
if not server_address:
raise ProxyError(502, "Transparent mode failure: could not resolve original destination.")
address_priority = AddressPriority.FROM_CONNECTION
self.log("transparent to %s:%s" % server_address)
if server_address:
self.set_server_address(server_address, address_priority)
self._handle_ssl()
while not self.close:
try:
protocol.handle_messages(self.conntype, self)
except protocol.ConnectionTypeChange:
self.log("Connection Type Changed: %s" % self.conntype)
continue
# FIXME: Do we want to persist errors?
except (ProxyError, tcp.NetLibError), e:
protocol.handle_error(self.conntype, self, e)
except Exception, e:
self.log(e.__class__)
import traceback
self.log(traceback.format_exc())
self.log(str(e))
self.del_server_connection()
self.log("clientdisconnect")
self.channel.tell("clientdisconnect", self)
def _handle_ssl(self):
"""
Helper function of .handle()
Check if we can already identify SSL connections.
If so, connect to the server and establish an SSL connection
"""
client_ssl = False
server_ssl = False
if self.config.transparent_proxy:
client_ssl = server_ssl = (self.server_conn.address.port in self.config.transparent_proxy["sslports"])
elif self.config.reverse_proxy:
client_ssl = server_ssl = (self.config.reverse_proxy[0] == "https")
# TODO: Make protocol generic (as with transparent proxies)
# TODO: Add SSL-terminating capatbility (SSL -> mitmproxy -> plain and vice versa)
if client_ssl or server_ssl:
self.establish_server_connection()
self.establish_ssl(client=client_ssl, server=server_ssl)
def del_server_connection(self):
"""
Deletes an existing server connection.
"""
if self.server_conn and self.server_conn.connection:
self.server_conn.finish()
self.log("serverdisconnect", ["%s:%s" % (self.server_conn.address.host, self.server_conn.address.port)])
self.channel.tell("serverdisconnect", self)
self.server_conn = None
self.server_address_priority = None
self.sni = None
def determine_conntype(self):
#TODO: Add ruleset to select correct protocol depending on mode/target port etc.
self.conntype = "http"
def set_server_address(self, address, priority):
"""
Sets a new server address with the given priority
@type priority: AddressPriority
"""
address = tcp.Address.wrap(address)
self.log("Try to set server address: %s:%s" % (address.host, address.port))
if self.server_conn and (self.server_conn.priority > priority):
self.log("Server address priority too low (is: %s, got: %s)" % (self.server_address_priority, priority))
return
if self.server_conn and (self.server_conn.address == address):
self.server_conn.priority = priority # Possibly increase priority
self.log("Addresses match, skip.")
return
server_conn = ServerConnection(address, priority)
if self.server_conn and self.server_conn.connection:
self.del_server_connection()
self.server_conn = server_conn
self.establish_server_connection()
else:
self.server_conn = server_conn
def establish_server_connection(self):
"""
Establishes a new server connection.
If there is already an existing server connection, the function returns immediately.
"""
if self.server_conn.connection:
return
self.log("serverconnect", ["%s:%s" % self.server_conn.address()[:2]])
self.channel.tell("serverconnect", self)
try:
self.server_conn.connect()
except tcp.NetLibError, v:
raise ProxyError(502, v)
def establish_ssl(self, client=False, server=False):
"""
Establishes SSL on the existing connection(s) to the server or the client,
as specified by the parameters. If the target server is on the pass-through list,
the conntype attribute will be changed and the SSL connection won't be wrapped.
A protocol handler must raise a ConnTypeChanged exception if it detects that this is happening
"""
# TODO: Implement SSL pass-through handling and change conntype
passthrough = [
"echo.websocket.org",
"174.129.224.73" # echo.websocket.org, transparent mode
]
if self.server_conn.address.host in passthrough or self.sni in passthrough:
self.conntype = "tcp"
return
# Logging
if client or server:
subs = []
if client:
subs.append("with client")
if server:
subs.append("with server (sni: %s)" % self.sni)
self.log("Establish SSL", subs)
if server:
if self.server_conn.ssl_established:
raise ProxyError(502, "SSL to Server already established.")
self.server_conn.establish_ssl(self.config.clientcerts, self.sni)
if client:
if self.client_conn.ssl_established:
raise ProxyError(502, "SSL to Client already established.")
dummycert = self.find_cert()
self.client_conn.convert_to_ssl(dummycert, self.config.certfile or self.config.cacert,
handle_sni=self.handle_sni)
def server_reconnect(self, no_ssl=False):
address = self.server_conn.address
had_ssl = self.server_conn.ssl_established
priority = self.server_address_priority
sni = self.sni
self.log("(server reconnect follows)")
self.del_server_connection()
self.set_server_address(address, priority)
self.establish_server_connection()
if had_ssl and not no_ssl:
self.sni = sni
self.establish_ssl(server=True)
def finish(self):
self.client_conn.finish()
def log(self, msg, subs=()):
msg = [
"%s:%s: %s" % (self.client_conn.address.host, self.client_conn.address.port, msg)
]
for i in subs:
msg.append(" -> " + i)
msg = "\n".join(msg)
self.channel.tell("log", Log(msg))
def find_cert(self):
if self.config.certfile:
with open(self.config.certfile, "rb") as f:
return certutils.SSLCert.from_pem(f.read())
else:
host = self.server_conn.address.host
sans = []
if not self.config.no_upstream_cert or not self.server_conn.ssl_established:
upstream_cert = self.server_conn.cert
if upstream_cert.cn:
host = upstream_cert.cn.decode("utf8").encode("idna")
sans = upstream_cert.altnames
ret = self.config.certstore.get_cert(host, sans, self.config.cacert)
if not ret:
raise ProxyError(502, "Unable to generate dummy cert.")
return ret
def handle_sni(self, connection):
"""
This callback gets called during the SSL handshake with the client.
The client has just sent the Sever Name Indication (SNI). We now connect upstream to
figure out which certificate needs to be served.
"""
try:
sn = connection.get_servername()
if sn and sn != self.sni:
self.sni = sn.decode("utf8").encode("idna")
self.log("SNI received: %s" % self.sni)
self.server_reconnect() # reconnect to upstream server with SNI
# Now, change client context to reflect changed certificate:
new_context = SSL.Context(SSL.TLSv1_METHOD)
new_context.use_privatekey_file(self.config.certfile or self.config.cacert)
dummycert = self.find_cert()
new_context.use_certificate(dummycert.x509)
connection.set_context(new_context)
# An unhandled exception in this method will core dump PyOpenSSL, so
# make dang sure it doesn't happen.
except Exception, e: # pragma: no cover
pass
class ProxyServerError(Exception):
pass
class ProxyServer(tcp.TCPServer):
allow_reuse_address = True
bound = True
def __init__(self, config, port, host='', server_version=version.NAMEVERSION):
"""
Raises ProxyServerError if there's a startup problem.
"""
self.config = config
self.server_version = server_version
try:
tcp.TCPServer.__init__(self, (host, port))
except socket.error, v:
raise ProxyServerError('Error starting proxy server: ' + v.strerror)
self.channel = None
def start_slave(self, klass, channel):
slave = klass(channel, self)
slave.start()
def set_channel(self, channel):
self.channel = channel
def handle_client_connection(self, conn, client_address):
h = ConnectionHandler(self.config, conn, client_address, self, self.channel, self.server_version)
h.handle()
h.finish()
class DummyServer:
bound = False
def __init__(self, config):
self.config = config
def start_slave(self, *args):
pass
def shutdown(self):
pass
# Command-line utils
def certificate_option_group(parser):
group = parser.add_argument_group("SSL")
group.add_argument(
"--cert", action="store",
type=str, dest="cert", default=None,
help="User-created SSL certificate file."
)
group.add_argument(
"--client-certs", action="store",
type=str, dest="clientcerts", default=None,
help="Client certificate directory."
)
def process_proxy_options(parser, options):
if options.cert:
options.cert = os.path.expanduser(options.cert)
if not os.path.exists(options.cert):
return parser.error("Manually created certificate does not exist: %s" % options.cert)
cacert = os.path.join(options.confdir, "mitmproxy-ca.pem")
cacert = os.path.expanduser(cacert)
if not os.path.exists(cacert):
certutils.dummy_ca(cacert)
body_size_limit = utils.parse_size(options.body_size_limit)
if options.reverse_proxy and options.transparent_proxy:
return parser.error("Can't set both reverse proxy and transparent proxy.")
if options.transparent_proxy:
if not platform.resolver:
return parser.error("Transparent mode not supported on this platform.")
trans = dict(
resolver=platform.resolver(),
sslports=TRANSPARENT_SSL_PORTS
)
else:
trans = None
if options.reverse_proxy:
rp = utils.parse_proxy_spec(options.reverse_proxy)
if not rp:
return parser.error("Invalid reverse proxy specification: %s" % options.reverse_proxy)
else:
rp = None
if options.forward_proxy:
fp = utils.parse_proxy_spec(options.forward_proxy)
if not fp:
return parser.error("Invalid forward proxy specification: %s" % options.forward_proxy)
else:
fp = None
if options.clientcerts:
options.clientcerts = os.path.expanduser(options.clientcerts)
if not os.path.exists(options.clientcerts) or not os.path.isdir(options.clientcerts):
return parser.error(
"Client certificate directory does not exist or is not a directory: %s" % options.clientcerts
)
if (options.auth_nonanonymous or options.auth_singleuser or options.auth_htpasswd):
if options.auth_singleuser:
if len(options.auth_singleuser.split(':')) != 2:
return parser.error("Invalid single-user specification. Please use the format username:password")
username, password = options.auth_singleuser.split(':')
password_manager = http_auth.PassManSingleUser(username, password)
elif options.auth_nonanonymous:
password_manager = http_auth.PassManNonAnon()
elif options.auth_htpasswd:
try:
password_manager = http_auth.PassManHtpasswd(options.auth_htpasswd)
except ValueError, v:
return parser.error(v.message)
authenticator = http_auth.BasicProxyAuth(password_manager, "mitmproxy")
else:
authenticator = http_auth.NullProxyAuth(None)
return ProxyConfig(
certfile=options.cert,
cacert=cacert,
clientcerts=options.clientcerts,
body_size_limit=body_size_limit,
no_upstream_cert=options.no_upstream_cert,
reverse_proxy=rp,
forward_proxy=fp,
transparent_proxy=trans,
authenticator=authenticator
)