first steps on tcp proxying

1 files changed, 88 insertions, 0 deletions

diff --git a/libmproxy/protocol.py b/libmproxy/protocol.py
new file mode 100644
index 00000000..5999fb06
--- /dev/null
+++ b/libmproxy/protocol.py
@@ -0,0 +1,88 @@
+from libmproxy.proxy import ProxyError, ConnectionHandler
+from netlib import http
+
+def handle_messages(conntype, connection_handler):
+    handler = None
+    if conntype == "http":
+        handler = HTTPHandler(connection_handler)
+    else:
+        raise NotImplementedError
+
+    return handler.handle_messages()
+
+
+class ProtocolHandler(object):
+    def __init__(self, c):
+        self.c = c
+
+class HTTPHandler(ProtocolHandler):
+
+    def handle_messages(self):
+        while self.handle_request():
+            pass
+        self.c.close = True
+
+    def handle_request(self):
+        request = self.read_request()
+        if request is None:
+            return
+        raise NotImplementedError
+
+    def read_request(self):
+        self.c.client_conn.rfile.reset_timestamps()
+
+        request_line = self.get_line(self.c.client_conn.rfile)
+        method, path, httpversion = http.parse_init(request_line)
+        headers = self.read_headers(authenticate=True)
+
+        if self.mode == "regular":
+            if method == "CONNECT":
+                r = http.parse_init_connect(request_line)
+                if not r:
+                    raise ProxyError(400, "Bad HTTP request line: %s"%repr(request_line))
+                host, port, _ = r
+                if self.config.forward_proxy:
+                    self.server_conn.wfile.write(request_line)
+                    for key, value in headers.items():
+                        self.server_conn.wfile.write("%s: %s\r\n"%(key, value))
+                    self.server_conn.wfile.write("\r\n")
+                else:
+                    self.server_address = (host, port)
+                    self.establish_server_connection()
+
+                self.handle_ssl()
+                self.mode = "transparent"
+                return
+            else:
+                r = http.parse_init_proxy(request_line)
+                if not r:
+                    raise ProxyError(400, "Bad HTTP request line: %s"%repr(request_line))
+                method, scheme, host, port, path, httpversion = r
+                if not self.config.forward_proxy:
+                    if (not self.server_conn) or (self.server_address != (host, port)):
+                        self.server_address = (host, port)
+                        self.establish_server_connection()
+
+    def get_line(self, fp):
+        """
+            Get a line, possibly preceded by a blank.
+        """
+        line = fp.readline()
+        if line == "\r\n" or line == "\n": # Possible leftover from previous message
+            line = fp.readline()
+        return line
+
+    def read_headers(self, authenticate=False):
+        headers = http.read_headers(self.client_conn.rfile)
+        if headers is None:
+            raise ProxyError(400, "Invalid headers")
+        if authenticate and self.config.authenticator:
+            if self.config.authenticator.authenticate(headers):
+                self.config.authenticator.clean(headers)
+            else:
+                raise ProxyError(
+                            407,
+                            "Proxy Authentication Required",
+                            self.config.authenticator.auth_challenge_headers()
+                       )
+        return headers
\ No newline at end of file