From 03f13453856e3af15dc3af81adcf3a80d1358da0 Mon Sep 17 00:00:00 2001
From: Aldo Cortesi <aldo@nullcube.com>
Date: Wed, 9 Mar 2011 13:15:31 +1300
Subject: [PATCH] Add an --anticache option to mitmdump.

This removes all headers that might cause a server to return 304-not-modified.

For now, all the new features are going into mitmdump - everything will be
ported over to mitmproxy once I have the feature set locked down.
---
 libmproxy/dump.py  | 11 +++++++----
 libmproxy/flow.py  |  3 +++
 libmproxy/proxy.py | 13 +++++++++++++
 mitmdump           |  6 ++++++
 test/test_flow.py  |  3 +--
 test/test_proxy.py |  9 +++++++++
 6 files changed, 39 insertions(+), 6 deletions(-)

diff --git a/libmproxy/dump.py b/libmproxy/dump.py
index 73ecc54d4..5cbb73896 100644
--- a/libmproxy/dump.py
+++ b/libmproxy/dump.py
@@ -6,16 +6,17 @@ class DumpError(Exception): pass
 
 class Options(object):
     __slots__ = [
+        "anticache",
+        "client_replay",
+        "keepserving",
         "kill",
         "request_script",
         "response_script",
+        "rheaders",
         "server_replay",
-        "client_replay",
+        "stickycookie",
         "verbosity",
         "wfile",
-        "rheaders",
-        "stickycookie",
-        "keepserving",
     ]
     def __init__(self, **kwargs):
         for k, v in kwargs.items():
@@ -83,6 +84,8 @@ class DumpMaster(flow.FlowMaster):
                 not options.keepserving
             )
 
+        self.anticache = options.anticache
+
     def _readflow(self, path):
         path = os.path.expanduser(path)
         try:
diff --git a/libmproxy/flow.py b/libmproxy/flow.py
index dff58fa05..0080f1d42 100644
--- a/libmproxy/flow.py
+++ b/libmproxy/flow.py
@@ -432,6 +432,7 @@ class FlowMaster(controller.Master):
         self.scripts = {}
         self.kill_nonreplay = False
         self.stickycookie_state = False
+        self.anticache = False
 
     def _runscript(self, f, script):
         #begin nocover
@@ -521,6 +522,8 @@ class FlowMaster(controller.Master):
             self.stickycookie_state.handle_request(f)
         if "request" in self.scripts:
             self._runscript(f, self.scripts["request"])
+        if self.anticache:
+            r.anticache()
         if self.server_playback:
             pb = self.do_server_playback(f)
             if not pb:
diff --git a/libmproxy/proxy.py b/libmproxy/proxy.py
index a4dc3e69e..48884c090 100644
--- a/libmproxy/proxy.py
+++ b/libmproxy/proxy.py
@@ -139,6 +139,19 @@ class Request(controller.Msg):
         # Have this request's cookies been modified by sticky cookies?
         self.stickycookie = False
 
+    def anticache(self):
+        """
+            Modifies this request to remove headers that might produce a cached
+            response. That is, we remove ETags and If-Modified-Since headers.
+        """
+        delheaders = [
+            "if-modified-since",
+            "if-none-match",
+        ]
+        for i in delheaders:
+            if i in self.headers:
+                del self.headers[i]
+
     def set_replay(self):
         self.client_conn = None
 
diff --git a/mitmdump b/mitmdump
index 814f2af37..972c76665 100755
--- a/mitmdump
+++ b/mitmdump
@@ -56,6 +56,11 @@ if __name__ == '__main__':
         action="store_true", dest="quiet",
         help="Quiet."
     )
+    parser.add_option(
+        "--anticache",
+        action="store_true", dest="anticache", default=False,
+        help="Strip out request headers that might cause the server to return 304-not-modified."
+    )
     parser.add_option(
         "--reqscript",
         action="store", dest="request_script", default=None,
@@ -131,6 +136,7 @@ if __name__ == '__main__':
         client_replay = options.client_replay,
         keepserving = options.keepserving,
         stickycookie = stickycookie,
+        anticache = options.anticache
     )
     if args:
         filt = " ".join(args)
diff --git a/test/test_flow.py b/test/test_flow.py
index 4090d483c..d72a18946 100644
--- a/test/test_flow.py
+++ b/test/test_flow.py
@@ -167,8 +167,6 @@ class uFlow(libpry.AutoTree):
         f.load_state(f2.get_state())
         assert f == f2
 
-
-
     def test_kill(self):
         f = tutils.tflow()
         f.request = tutils.treq()
@@ -370,6 +368,7 @@ class uFlowMaster(libpry.AutoTree):
     def test_all(self):
         s = flow.State()
         fm = flow.FlowMaster(None, s)
+        fm.anticache = True
         req = tutils.treq()
 
         fm.handle_clientconnect(req.client_conn)
diff --git a/test/test_proxy.py b/test/test_proxy.py
index e5b3ed16c..3bc5bcdb8 100644
--- a/test/test_proxy.py
+++ b/test/test_proxy.py
@@ -78,6 +78,15 @@ class uRequest(libpry.AutoTree):
         assert r.url() == u
         assert r.assemble()
 
+    def test_anticache(self):
+        h = utils.Headers()
+        r = proxy.Request(None, "host", 22, "https", "GET", "/", h, "content")
+        h["if-modified-since"] = ["test"]
+        h["if-none-match"] = ["test"]
+        r.anticache()
+        assert not "if-modified-since" in r.headers
+        assert not "if-none-match" in r.headers
+
     def test_getset_state(self):
         h = utils.Headers()
         h["test"] = ["test"]