85664f1e31
This diff contains significant improvements over the previous implementation of the torsf experiment. We add support for configuring different rendezvous methods after the convo at https://github.com/ooni/probe/issues/2004. In doing that, I've tried to use a terminology that is consistent with the names being actually used by tor developers. In terms of what to do next, this diff basically instruments torsf to always rendezvous using domain fronting. Yet, it's also possible to change the rendezvous method from the command line, when using miniooni, which allows to experiment a bit more. In the same vein, by default we use a persistent tor datadir, but it's also possible to use a temporary datadir using the cmdline. Here's how a generic invocation of `torsf` looks like: ```bash ./miniooni -O DisablePersistentDatadir=true \ -O RendezvousMethod=amp \ -O DisableProgress=true \ torsf ``` (The default is `DisablePersistentDatadir=false` and `RendezvousMethod=domain_fronting`.) With this implementation, we can start measuring whether snowflake and tor together can boostrap, which seems the most important thing to focus on at the beginning. Understanding why the bootstrap most often does not converge with a temporary datadir on Android devices remains instead an open problem for now. (I'll also update the relevant issues or create new issues after commit this.) We also address some methodology improvements that were proposed in https://github.com/ooni/probe/issues/1686. Namely: 1. we record the tor version; 2. we include the bootstrap percentage by reading the logs; 3. we set the anomaly key correctly; 4. we measure the bytes send and received (by `tor` not by `snowflake`, since doing it for snowflake seems more complex at this stage). What remains to be done is the possibility of including Snowflake events into the measurement, which is not possible until the new improvements at common/event in snowflake.git are included into a tagged version of snowflake itself. (I'll make sure to mention this aspect to @cohosh in https://github.com/ooni/probe/issues/2004.) |
||
|---|---|---|
| .. | ||
| chapter01 | ||
| chapter02 | ||
| chapter03 | ||
| chapter04 | ||
| README.md | ||
Tutorial: rewriting the torsf experiment
This tutorial teaches you how to write a minimal implementation of the torsf experiment. We will do that in four steps.
In the first step we will write a main.go
function that runs the existing torsf implementation.
In the second step we will modify the existing code to launch an empty experiment instead.
In the third step we will start to fill in
the empty experiment to more closely simulate a real implementation
of the torsf experiment.
In the fourth step we will replace the code
simulating a real torsf experiment with a minimal implementation
of such an experiment that uses other code in ooni/probe-cli to
attempt to bootstrap tor over Snowflake.