This diff changes the data format to prefer "udp" to "quic" everywhere we were previously using "quic".
Previously, the code inconsistently used "quic" for operations where we knew we were using "quic" and "udp" otherwise (e.g., for generic operations like ReadFrom).
While it would be more correct to say that a specific HTTP request used "quic" rather than "udp", using "udp" consistently allows one to see how distinct events such as ReadFrom and an handshake all refer to the same address, port, and protocol triple. Therefore, this change makes it easier to programmatically unpack a single measurement and create endpoint stats.
Before implementing this change, I discussed the problem with @hellais who mentioned that ooni/data is not currently using the "quic" string anywhere. I know that ooni/pipeline also doesn't rely on this string. The only users of this feature have been research-oriented experiments such as urlgetter, for which such a change would actually be acceptable.
See https://github.com/ooni/probe/issues/2238 and https://github.com/ooni/spec/pull/262.
* feat(netxlite): support extracting the CNAME
Closes https://github.com/ooni/probe/issues/2225
* fix(netxlite): attempt to increase coverage and improve tests
1. dnsovergetaddrinfo: specify the behavior of a DNSResponse returned
by this file to make it line with normal responses and write unit tests
to make sure we adhere to expectations;
2. dnsoverudp: make sure we wait to deferred responses also w/o a
custom context and post on a private channel and test that;
3. utls: recognize that we can actually write a test for NetConn and
what needs to change when we'll use go1.19 by default will just be
a cast that at that point can be removed.
* cleanup: remove UnderlyingNetworkLibrary and TProxy
While there, replace mixture of mocking and real connections inside
quicping with pure mocking of network connections.
Closes https://github.com/ooni/probe/issues/2224
* cleanup: we don't need a SimpleResolver now
This type was only used by UnderlyingNetworkLibrary and all the
rest of the code uses Resolver. So, let's avoid complexity by zapping
the SimpleResolver type and merging it inside Resolver.
* upgrade to our go.mod enabled of psiphon-tunnel-core such that
we're now using v2.0.24 of the tunnel-core;
* upgrade to the latest lucas-clemente/quic-go release;
* upgrade to the latest ooni/oohttp release (which is based on go1.19
but the diff seems good enough to continue using go1.18.x as well);
* upgrade to the latest ooni/oocrypto release (for which we can make the
same remarks regarding using go1.18.x);
* deal with changes in lucas-clemente/quic-go API as well as changes
in what a go1.19 *tls.Conn compatible type should look like.
Unfortunately, we cannot switch to go1.19 because psiphon forks quic-go
and their fork's still not building using such a version of go.
Part of ooni/probe#2211.
## 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/2158
- [x] if you changed anything related how experiments work and you need to reflect these changes in the ooni/spec repository, please link to the related ooni/spec pull request: https://github.com/ooni/spec/pull/250
## Description
This diff refactors the codebase to reimplement tlsping and tcpping
to use the step-by-step measurements style.
See docs/design/dd-003-step-by-step.md for more information on the
step-by-step measurement style.
Acknowledge that transports MAY be used in isolation (i.e., outside
of a Resolver) and add support for wrapping.
Ensure that every factory that creates an unwrapped type is named
accordingly to hopefully ensure there are no surprises.
Implement DNSTransport wrapping and use a technique similar to the
one used by Dialer to customize the DNSTransport while constructing
more complex data types (e.g., a specific resolver).
Ensure that the stdlib resolver's own "getaddrinfo" transport (1)
is wrapped and (2) could be extended during construction.
This work is part of my ongoing effort to bring to this repository
websteps-illustrated changes relative to netxlite.
Ref issue: https://github.com/ooni/probe/issues/2096
Rather than passing functions to construct complex objects such
as Dialer and QUICDialer, pass interface implementations.
Ensure that a nil implementation does not cause harm.
Make Saver implement the correct interface either directly or
indirectly. We need to implement the correct interface indirectly
for TCP conns (or connected UDP sockets) because we have two
distinct use cases inside netx: observing just the connect event
and observing just the I/O events.
With this change, the construction of composed Dialers and
QUICDialers is greatly simplified and more obvious.
Part of https://github.com/ooni/probe/issues/2121
In https://github.com/ooni/probe/issues/2029#issuecomment-1140805266, we
explained why calling it "netgo" would be incorrect.
In other words, we can get the platform's `getaddrinfo` as long as
we're not cross compiling. We do cross compile `ooniprobe`, actually
it's not even possible to cross compile it.
For increased accuracy, we should stop cross compiling `miniooni`
as well, so it would also directly use `getaddrinfo`.
This diff fixes at the same time ooni/probe-cli and ooni/spec
and we'll open two pull requests in parallel.
After https://github.com/ooni/probe-cli/pull/764, the build for
CGO_ENABLED=0 has been broken for miniooni:
https://github.com/ooni/probe-cli/runs/6636995859?check_suite_focus=true
Likewise, it's not possible to run tests with CGO_ENABLED=0.
To make tests work with `CGO_ENABLED=0`, I needed to sacrifice some
unit tests run for the CGO case. It is not fully clear to me what was happening
here, but basically `getaddrinfo_cgo_test.go` was compiled with CGO
being disabled, even though the ``//go:build cgo` flag was specified.
Additionally, @hellais previously raised a valid point in the review
of https://github.com/ooni/probe-cli/pull/698:
> Another issue we should consider is that, if I understand how
> this works correctly, depending on whether or not we have built
> with CGO_ENABLED=0 on or not, we are going to be measuring
> things in a different way (using our cgo inspired getaddrinfo
> implementation or using netgo). This might present issues when
> analyzing or interpreting the data.
>
> Do we perhaps want to add some field to the output data format that
> gives us an indication of which DNS resolution code was used to
> generate the the metric?
This comment is relevant to the current commit because
https://github.com/ooni/probe-cli/pull/698 is the previous
iteration of https://github.com/ooni/probe-cli/pull/764.
So, while fixing the build and test issues, let us also distinguish
between the CGO_ENABLED=1 and CGO_ENABLED=0 cases.
Before this commit, OONI used "system" to indicate the case where
we were using net.DefaultResolver. This behavior dates back to the
Measurement Kit days. While it is true that ooni/probe-engine and
ooni/probe-cli could have been using netgo in the past when we
said "system" as the resolver, it also seems reasonable to continue
to use "system" top indicate getaddrinfo.
So, the choice here is basically to use "netgo" from now on to
indicate the cases in which we were built with CGO_ENABLED=0.
This change will need to be documented into ooni/spec along with
the introduction of the `android_dns_cache_no_data` error.
## 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/2029
- [x] if you changed anything related how experiments work and you need to reflect these changes in the ooni/spec repository, please link to the related ooni/spec pull request: https://github.com/ooni/spec/pull/242
This diff refactors the DNSTransport model to receive in input a DNSQuery and return in output a DNSResponse.
The design of DNSQuery and DNSResponse takes into account the use case of a transport using getaddrinfo, meaning that we don't need to serialize and deserialize messages when using getaddrinfo.
The current codebase does not use a getaddrinfo transport, but I wrote one such a transport in the Websteps Winter 2021 prototype (https://github.com/bassosimone/websteps-illustrated/).
The design conversation that lead to producing this diff is https://github.com/ooni/probe/issues/2099
Previously, the DNS decoder did not check whether it was parsing
a DNS query or a DNS response, which was wrong.
As a side note, it seems I am using "reply" in the codebase instead
of "response". The latter seems correct DNS terminology.
This diff has been extracted from 9249d14f80
See https://github.com/ooni/probe/issues/2096.
This diff has been extracted from c2f7ccab0e
See https://github.com/ooni/probe/issues/2096
While there, export DecodeReply to decode a raw reply without
interpreting the Rcode or parsing the results, which seems a
nice extra feature to have to more flexibly parse DNS replies
in other parts of the codebase.
* quic-go upgrade: replaced Session/EarlySession with Connection/EarlyConnection
* quic-go upgrade: added context to RoundTripper.Dial
* quic-go upgrade: made corresponding changes to tutorial
* quic-go upgrade: changed sess variable instances to qconn
* quic-go upgrade: made corresponding changes to tutorial
* cleanup: remove unnecessary comments
Those comments made sense in terms of illustrating the changes
but they're going to be less useful once we merge.
* fix(go.mod): apparently we needed `go1.18.1 mod tidy`
VSCode just warned me about this. It seems fine to apply this
change as part of the pull request at hand.
* cleanup(netxlite): http3dialer can be removed
We used to use http3dialer to glue a QUIC dialer, which had a
context as its first argument, to the Dial function used by the
HTTP3 transport, which did not have a context as its first
argument.
Now that HTTP3 transport has a Dial function taking a context as
its first argument, we don't need http3dialer
anymore, since we can use the QUIC dialer directly.
Cc: @DecFox
* Revert "cleanup(netxlite): http3dialer can be removed"
This reverts commit c62244c620cee5fadcc2ca89d8228c8db0b96add
to investigate the build failure mentioned at
https://github.com/ooni/probe-cli/pull/715#issuecomment-1119450484
* chore(netx): show that test was already broken
We didn't see the breakage before because we were not using
the created transport, but the issue of using a nil dialer was
already present before, we just didn't see it.
Now we understand why removing the http3transport in
c62244c620cee5fadcc2ca89d8228c8db0b96add did cause the
breakage mentioned at
https://github.com/ooni/probe-cli/pull/715#issuecomment-1119450484
* fix(netx): convert broken integration test to working unit test
There's no point in using the network here. Add a fake dialer that
breaks and ensure we're getting the expected error.
We've now improved upon the original test because the original test was
not doing anything while now we're testing whether we get back a QUIC
dialer that _can be used_.
After this commit, I can then readd the cleanup commit
c62244c620cee5fadcc2ca89d8228c8db0b96add and it won't be
broken anymore (at least, this is what I expected to happen).
* Revert "Revert "cleanup(netxlite): http3dialer can be removed""
This reverts commit 0e254bfc6ba3bfd65365ce3d8de2c8ec51b925ff
because now we should have fixed the broken test.
Co-authored-by: decfox <decfox>
Co-authored-by: Simone Basso <bassosimone@gmail.com>
This diff introduces a new package called `./internal/archival`. This package collects data from `./internal/model` network interfaces (e.g., `Dialer`, `QUICDialer`, `HTTPTransport`), saves such data into an internal tabular data format suitable for on-line processing and analysis, and allows exporting data into the OONI data format.
The code for collecting and the internal tabular data formats are adapted from `measurex`. The code for formatting and exporting OONI data-format-compliant structures is adapted from `netx/archival`.
My original objective was to _also_ (1) fully replace `netx/archival` with this package and (2) adapt `measurex` to use this package rather than its own code. Both operations seem easily feasible because: (a) this code is `measurex` code without extensions that are `measurex` related, which will need to be added back as part of the process; (b) the API provided by this code allows for trivially converting from using `netx/archival` to using this code.
Yet, both changes should not be taken lightly. After implementing them, there's need to spend some time doing QA and ensuring all nettests work as intended. However, I am planning a release in the next two weeks, and this QA task is likely going to defer the release. For this reason, I have chosen to commit the work done so far into the tree and defer the second part of this refactoring for a later moment in time. (This explains why the title mentions "1/N").
On a more high-level perspective, it would also be beneficial, I guess, to explain _why_ I am doing these changes. There are two intertwined reasons. The first reason is that `netx/archival` has shortcomings deriving from its original https://github.com/ooni/netx legacy. The most relevant shortcoming is that it saves all kind of data into the same tabular structure named `Event`. This design choice is unfortunate because it does not allow one to apply data-type specific logic when processing the results. In turn, this choice results in complex processing code. Therefore, I believe that replacing the code with event-specific data structures is clearly an improvement in terms of code maintainability and would quite likely lead us to more confidently change and evolve the codebase.
The second reason why I would like to move forward these changes is to unify the codepaths used for measuring. At this point in time, we basically have two codepaths: `./internal/engine/netx` and `./internal/measurex`. They both have pros and cons and I don't think we want to rewrite whole experiments using `netx`. Rather, what we probably want is to gradually merge these two codepaths such that `netx` is a set of abstractions on top of `measurex` (which is more low-level and has a more-easily-testable design). Because saving events and generating an archival data format out of them consists of at least 50% of the complexity of both `netx` and `measurex`, it seems reasonable to unify this archival-related part of the two codebases as the first step.
At the highest level of abstraction, these changes are part of the train of changes which will eventually lead us to bless `websteps` as a first class citizen in OONI land. Because `websteps` requires different underlying primitives, I chose to develop these primitives from scratch rather than wrestling with `netx`, which used another model. The model used by `websteps` is that we perform each operation in isolation and immediately we save the results, while `netx` creates whole data structures and collects all the events happening via tracing. We believe the model used by `websteps` to be better because it does not require your code to figure out everything that happened after the measurement, which is a source of subtle bugs in the current implementation. So, when I started implementing websteps I extracted the bits of `netx` that could also be beneficial to `websteps` into a separate library, thus `netxlite` was born.
The reference issue describing merging the archival of `netx` and `measurex` is https://github.com/ooni/probe/issues/1957. As of this writing the issue still references the original plan, which I could not complete by the end of this Sprint, so I am going to adapt the text of the issue to only refer to what was done in here next. Of course, I also need follow-up issues.
## 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