Files
mitmproxy/mitmproxy/proxy/root_context.py
2016-10-20 11:27:05 +13:00

123 lines
4.6 KiB
Python

from mitmproxy import log
from mitmproxy import exceptions
from mitmproxy.proxy import protocol
from mitmproxy.proxy import modes
class RootContext:
"""
The outermost context provided to the root layer.
As a consequence, every layer has access to methods and attributes defined here.
Attributes:
client_conn:
The :py:class:`client connection <mitmproxy.connections.ClientConnection>`.
channel:
A :py:class:`~mitmproxy.controller.Channel` to communicate with the FlowMaster.
Provides :py:meth:`.ask() <mitmproxy.controller.Channel.ask>` and
:py:meth:`.tell() <mitmproxy.controller.Channel.tell>` methods.
config:
The :py:class:`proxy server's configuration <mitmproxy.proxy.ProxyConfig>`
"""
def __init__(self, client_conn, config, channel):
self.client_conn = client_conn
self.channel = channel
self.config = config
def next_layer(self, top_layer):
"""
This function determines the next layer in the protocol stack.
Arguments:
top_layer: the current innermost layer.
Returns:
The next layer
"""
layer = self._next_layer(top_layer)
return self.channel.ask("next_layer", layer)
def _next_layer(self, top_layer):
try:
d = top_layer.client_conn.rfile.peek(3)
except exceptions.TcpException as e:
raise exceptions.ProtocolException(str(e))
client_tls = protocol.is_tls_record_magic(d)
# 1. check for --ignore
if self.config.check_ignore:
ignore = self.config.check_ignore(top_layer.server_conn.address)
if not ignore and client_tls:
try:
client_hello = protocol.TlsClientHello.from_client_conn(self.client_conn)
except exceptions.TlsProtocolException as e:
self.log("Cannot parse Client Hello: %s" % repr(e), "error")
else:
ignore = self.config.check_ignore((client_hello.sni, 443))
if ignore:
return protocol.RawTCPLayer(top_layer, ignore=True)
# 2. Always insert a TLS layer, even if there's neither client nor server tls.
# An inline script may upgrade from http to https,
# in which case we need some form of TLS layer.
if isinstance(top_layer, modes.ReverseProxy):
return protocol.TlsLayer(top_layer, client_tls, top_layer.server_tls, top_layer.server_conn.address.host)
if isinstance(top_layer, protocol.ServerConnectionMixin) or isinstance(top_layer, protocol.UpstreamConnectLayer):
return protocol.TlsLayer(top_layer, client_tls, client_tls)
# 3. In Http Proxy mode and Upstream Proxy mode, the next layer is fixed.
if isinstance(top_layer, protocol.TlsLayer):
if isinstance(top_layer.ctx, modes.HttpProxy):
return protocol.Http1Layer(top_layer, "regular")
if isinstance(top_layer.ctx, modes.HttpUpstreamProxy):
return protocol.Http1Layer(top_layer, "upstream")
# 4. Check for other TLS cases (e.g. after CONNECT).
if client_tls:
return protocol.TlsLayer(top_layer, True, True)
# 4. Check for --tcp
if self.config.check_tcp(top_layer.server_conn.address):
return protocol.RawTCPLayer(top_layer)
# 5. Check for TLS ALPN (HTTP1/HTTP2)
if isinstance(top_layer, protocol.TlsLayer):
alpn = top_layer.client_conn.get_alpn_proto_negotiated()
if alpn == b'h2':
return protocol.Http2Layer(top_layer, 'transparent')
if alpn == b'http/1.1':
return protocol.Http1Layer(top_layer, 'transparent')
# 6. Check for raw tcp mode
is_ascii = (
len(d) == 3 and
# expect A-Za-z
all(65 <= x <= 90 or 97 <= x <= 122 for x in d)
)
if self.config.options.rawtcp and not is_ascii:
return protocol.RawTCPLayer(top_layer)
# 7. Assume HTTP1 by default
return protocol.Http1Layer(top_layer, 'transparent')
def log(self, msg, level, subs=()):
"""
Send a log message to the master.
"""
full_msg = [
"{}: {}".format(repr(self.client_conn.address), msg)
]
for i in subs:
full_msg.append(" -> " + i)
full_msg = "\n".join(full_msg)
self.channel.tell("log", log.LogEntry(full_msg, level))
@property
def layers(self):
return []
def __repr__(self):
return "RootContext"