This patch has no effect on the C tor build.

Adds a function hashx_rng_callback() to the hashx API, defined only
when HASHX_RNG_CALLBACK is defined. This is then used in the Rust
wrapper to implement a similar rng_callback().

Included some minimal test cases. This code is intented for
use in cross-compatibility fuzzing tests which drive multiple
implementations of hashx with the same custom Rng stream.

Signed-off-by: Micah Elizabeth Scott <beth@torproject.org>

Include a basic Rust wrapper for Equi-X and HashX

See merge request tpo/core/tor!733

The idea behind this is that we may want to start exporting more pieces
of c-tor as Rust crates so that Arti can perform cross compatibility and
comparison testing using Rust tooling.

This turns the 'tor' repo into a Cargo workspace, and adds one crate to
start with: "tor-c-equix", rooted in src/ext/equix. This actually
includes both Equi-X itself and HashX, since there's less overall
duplication if we package these together instead of packaging HashX
separately.

This patch adds a basic safe Rust interface, but doesn't expose any
additional internals for testing purposes.

No changes to the C code here or the normal Tor build system.

Signed-off-by: Micah Elizabeth Scott <beth@torproject.org>

Signed-off-by: David Goulet <dgoulet@torproject.org>

Signed-off-by: David Goulet <dgoulet@torproject.org>

Close #40824

Signed-off-by: David Goulet <dgoulet@torproject.org>

Warn when operating as bridge and exit

Closes #40819

See merge request tpo/core/tor!730

fix non-fatal assertion when rotate_onion_key fails

Closes #40554

See merge request tpo/core/tor!729

gitlab-ci: fix apt conf syntax for Acquire::Retries

See merge request tpo/core/tor!705

Clarify where geoip-db-tool is.

See merge request tpo/core/tor!728

Somebody emailed me to ask where to find the tool that generated our
geoip file. I was about to suggest that they search for "geoip-db-tool",
when I found that you can't actually search for that and find our code.

Therefore, I'm adding a link.

trivial typo fix in comment

See merge request tpo/core/tor!726

Rotate to a new L2 vanguard whenever an existing one loses the
Stable or Fast flag. Previously, we would leave these relays in the
L2 vanguard list but never use them, and if all of our vanguards
end up like this we wouldn't have any middle nodes left to choose
from so we would fail to make onion-related circuits.

Fixes bug 40805; bugfix on 0.4.7.1-alpha.

Remove unused congestion control and BDP algs

See merge request tpo/core/tor!725

Update congestion control params and add test vectors

See merge request tpo/core/tor!724