fix #313

libmproxy/protocol/http.py

@@ -930,9 +930,14 @@ class HTTPHandler(ProtocolHandler, TemporaryServerChangeMixin):
 
             if (http.connection_close(flow.request.httpversion, flow.request.headers) or
                     http.connection_close(flow.response.httpversion, flow.response.headers)):
-                return False
+                if flow.request.form_in == "authority" and flow.response.code == 200:
+                    # Workaround for https://github.com/mitmproxy/mitmproxy/issues/313:
+                    # Some proxies (e.g. Charles) send a CONNECT response with HTTP/1.0 and no Content-Length header
+                    pass
+                else:
+                    return False
 
-            if flow.request.form_in == "authority":
+            if flow.request.form_in == "authority" and flow.response.code == 200:
                 self.ssl_upgrade()
 
             # If the user has changed the target server on this connection,
@@ -1039,6 +1044,7 @@ class HTTPHandler(ProtocolHandler, TemporaryServerChangeMixin):
                     flow.server_conn = self.c.server_conn  # Update server_conn attribute on the flow
                     self.c.client_conn.send(
                         'HTTP/1.1 200 Connection established\r\n' +
+                        'Content-Length: 0\r\n' +
                         ('Proxy-agent: %s\r\n' % self.c.server_version) +
                         '\r\n'
                     )

test/test_protocol_http.py

@@ -54,7 +54,6 @@ class TestHTTPRequest:
         r = tutils.treq()
         tutils.raises("Invalid request form", r._assemble, "antiauthority")
 
-
     def test_set_url(self):
         r = tutils.treq_absolute()
         r.set_url("https://otheraddress:42/ORLY")
@@ -127,6 +126,21 @@ class TestProxyChainingSSL(tservers.HTTPChainProxyTest):
                                                               # request from chain[1] to proxy
         assert self.proxy.tmaster.state.flow_count() == 1  # request from chain[0] (regular proxy doesn't store CONNECTs)
 
+    def test_closing_connect_response(self):
+        """
+        https://github.com/mitmproxy/mitmproxy/issues/313
+        """
+        def handle_request(r):
+            r.httpversion = (1,0)
+            del r.headers["Content-Length"]
+            r.reply()
+        _handle_request = self.chain[0].tmaster.handle_request
+        self.chain[0].tmaster.handle_request = handle_request
+        try:
+            assert self.pathoc().request("get:/p/418").status_code == 418
+        finally:
+            self.chain[0].tmaster.handle_request = _handle_request
+
 class TestProxyChainingSSLReconnect(tservers.HTTPChainProxyTest):
     ssl = True