This diff adds to miniooni support for using the torsf tunnel. Such a
tunnel consists of a snowflake pluggable transport in front of a custom
instance of tor and requires tor to be installed.
The usage is like:
```
./miniooni --tunnel=torsf [...]
```
The default snowflake rendezvous method is "domain_fronting". You can
select the AMP cache instead using "amp":
```
./miniooni --snowflake-rendezvous=amp --tunnel=torsf [...]
```
Part of https://github.com/ooni/probe/issues/1955
## Checklist
- [x] I have read the [contribution guidelines](https://github.com/ooni/probe-cli/blob/master/CONTRIBUTING.md)
- [x] reference issue for this pull request: https://github.com/ooni/probe/issues/1885
- [x] related ooni/spec pull request: N/A
Location of the issue tracker: https://github.com/ooni/probe
## Description
This PR contains a set of changes to move important interfaces and data types into the `./internal/model` package.
The criteria for including an interface or data type in here is roughly that the type should be important and used by several packages. We are especially interested to move more interfaces here to increase modularity.
An additional side effect is that, by reading this package, one should be able to understand more quickly how different parts of the codebase interact with each other.
This is what I want to move in `internal/model`:
- [x] most important interfaces from `internal/netxlite`
- [x] everything that was previously part of `internal/engine/model`
- [x] mocks from `internal/netxlite/mocks` should also be moved in here as a subpackage
When preparing a tutorial for netxlite, I figured it is easier
to tell people "hey, this is the package you should use for all
low-level networking stuff" rather than introducing people to
a set of packages working together where some piece of functionality
is here and some other piece is there.
Part of https://github.com/ooni/probe/issues/1591
## Description
This PR continues the refactoring of `netx` under the following principles:
1. do not break the rest of the tree and do not engage in extensive tree-wide refactoring yet
2. move under `netxlite` clearly related subpackages (e.g., `iox`, `netxmocks`)
3. move into `internal/netxlite/internal` stuff that is clearly private of `netxlite`
4. hide implementation details in `netxlite` pending new factories
5. refactor `tls` code in `netxlite` to clearly separate `crypto/tls` code from `utls` code
After each commit, I run `go test -short -race ./...` locally. Each individual commit explains what it does. I will squash, but this operation will preserve the original commit titles, so this will give further insight on each step.
## Commits
* refactor: rename netxmocks -> netxlite/mocks
Part of https://github.com/ooni/probe/issues/1591
* refactor: rename quicx -> netxlite/quicx
See https://github.com/ooni/probe/issues/1591
* refactor: rename iox -> netxlite/iox
Regenerate sources and make sure the tests pass.
See https://github.com/ooni/probe/issues/1591.
* refactor(iox): move MockableReader to netxlite/mocks
See https://github.com/ooni/probe/issues/1591
* refactor(netxlite): generator is an implementation detail
See https://github.com/ooni/probe/issues/1591
* refactor(netxlite): separate tls and utls code
See https://github.com/ooni/probe/issues/1591
* refactor(netxlite): hide most types but keep old names as legacy
With this change we avoid breaking the rest of the tree, but we start
hiding some implementation details a bit. Factories will follow.
See https://github.com/ooni/probe/issues/1591
* fix(all): introduce and use iox.ReadAllContext
This improvement over the ioutil.ReadAll utility returns early
if the context expires. This enables us to unblock stuck code in
case there's censorship confounding the TCP stack.
See https://github.com/ooni/probe/issues/1417.
Compared to the functionality postulated in the above mentioned
issue, I choose to be more generic and separate limiting the
maximum body size (not implemented here) from using the context
to return early when reading a body (or any other reader).
After implementing iox.ReadAllContext, I made sure we always
use it everywhere in the tree instead of ioutil.ReadAll.
This includes many parts of the codebase where in theory we don't
need iox.ReadAllContext. Though, changing all the places makes
checking whether we're not using ioutil.ReadAll where we should
not be using it easy: `git grep` should return no lines.
* Update internal/iox/iox_test.go
* fix(ndt7): treat context errors as non-errors
The rationale is explained by the comment documenting reduceErr.
* Update internal/engine/experiment/ndt7/download.go
* feat: introduce ptx package for pluggable transports dialers
Version 2 of the pluggable transports specification defines a function
that's like `Dial() (net.Conn, error`).
Because we use contexts as much as possible in `probe-cli`, we are
wrapping such an interface into a `DialContext` func.
The code for obfs4 is adapted from https://github.com/ooni/probe-cli/pull/341.
The code for snowflake is significantly easier than it is in
https://github.com/ooni/probe-cli/pull/341, because now Snowflake
supports the PTv2 spec (thanks @cohosh!).
The code for setting up a pluggable transport listener has also
been adapted from https://github.com/ooni/probe-cli/pull/341.
We cannot merge this code yet, because we need unit testing, yet the
newly added code already seems suitable for these use cases:
1. testing by dialing and seeing whether we can dial (which is not
very useful but still better than not doing it);
2. spawning tor+pluggable transports for circumvention (we need a
little more hammering like we did in https://github.com/ooni/probe-cli/pull/341,
which is basically https://github.com/ooni/probe/issues/1565, and then
we will be able to do that, as demonstrated by the new, simple client which
already allows us to use pluggable transports with tor);
3. testing by launching tor (when available) with a set of
pluggable transports (which depends on https://github.com/ooni/probe-engine/issues/897
and has not been assigned an issue yet).
* fix: tweaks after self code-review
* feat: write quick tests for ptx/obfs4
(They run in 0.4s, so I think it's fine for them to always run.)
* feat(ptx/snowflake): write unit and integration tests
* feat: create a fake PTDialer
The idea is that we'll use this simpler PTDialer for testing.
* feat: finish writing tests for new package
* Apply suggestions from code review
* Update internal/ptx/dependencies_test.go
Co-authored-by: Arturo Filastò <arturo@openobservatory.org>
* Update internal/ptx/dependencies_test.go
Co-authored-by: Arturo Filastò <arturo@openobservatory.org>
* chore: use as testing bridge one that's used by tor browser
The previous testing bridge used to be used by tor browser but
it was subsequently removed here:
e26e91bef8
See https://github.com/ooni/probe-cli/pull/373#discussion_r649820724
Co-authored-by: Arturo Filastò <arturo@openobservatory.org>
