mitmproxy is a console tool that allows interactive examination and
modification of HTTP traffic. It differs from mitmdump in that all flows are
kept in memory, which means that it’s intended for taking and manipulating
small-ish samples. Use the
? shortcut key to view, context-sensitive
documentation from any mitmproxy screen.
The flow list shows an index of captured flows in chronological order.
- 1: A GET request, returning a 302 Redirect response.
- 2: A GET request, returning 16.75kb of text/html data.
- 3: A replayed request.
- 4: Intercepted flows are indicated with orange text. The user may edit
these flows, and then accept them (using the
akey) to continue. In this case, the request has been intercepted on the way to the server.
- 5: A response intercepted from the server on the way to the client.
- 6: The event log can be toggled on and off using the
eshortcut key. This pane shows events and errors that may not result in a flow that shows up in the flow pane.
- 7: Flow count.
- 8: Various information on mitmproxy’s state. In this case, we have an
interception pattern set to
- 9: Bind address indicator - mitmproxy is listening on port 8080 of all interfaces.
The Flow View lets you inspect and manipulate a single flow:
- 1: Flow summary.
- 2: The Request/Response tabs, showing you which part of the flow you are
currently viewing. In the example above, we’re viewing the Response. Hit
tabto switch between the Response and the Request.
- 3: Headers.
- 4: Body.
- 5: View Mode indicator. In this case, we’re viewing the body in hex mode. The other
available modes are pretty, which uses a number of heuristics to show you a friendly
view of various content types, and raw, which shows you exactly what’s there without any
changes. You can change modes using the
Much of the data that we’d like to interact with in mitmproxy is structured. For instance, headers, queries and form data can all be thought of as a list of key/value pairs. Mitmproxy has a built-in editor that lays this type of data out in a grid for easy manipulation.
At the moment, the Grid Editor is used in four parts of mitmproxy:
- Editing request or response headers (
efor edit, then
hfor headers in flow view)
- Editing a query string (
efor edit, then
qfor query in flow view)
- Editing a URL-encoded form (
efor edit, then
ffor form in flow view)
- Editing replacement patterns (
Ofor options, then
Rfor Replacement Patterns)
If there is is no data, an empty editor will be started to let you add some. Here is the editor showing the headers from a request:
To edit, navigate to the key or value you want to modify using the arrow or vi navigation keys, and press enter. The background color will change to show that you are in edit mode for the specified field:
Modify the field as desired, then press escape to exit edit mode when you’re
done. You can also add a row (
a key), delete a row (
d key), spawn an
external editor on a field (
e key). Be sure to consult the context-sensitive
? key) for more.
mitmproxy‘s interception functionality lets you pause an HTTP request or response, inspect and modify it, and then accept it to send it on to the server or client.
1: Set an interception pattern¶
i to set an interception pattern. In this case, the
pattern tells mitmproxy to intercept all requests. For complete filter
syntax, see the Filter expressions section of the documentation,
or the built-in help function in mitmproxy.
2: Intercepted connections are indicated with orange text:¶
3: You can now view and modify the request:¶
In this case, we viewed the request by selecting it, pressed
e for “edit”
m for “method” to change the HTTP request method.
4: Accept the intercept to continue:¶
Finally, we press
a to accept the modified request, which is then sent on to
the server. In this case, we changed the request from an HTTP GET to
OPTIONS, and Google’s server has responded with a 405 “Method not allowed”.