The DoS potential is slightly higher in C now due to some differences to the
Rust code, see the C_RUST_DIFFERS tags in src/rust/protover/tests/protover.rs.
Also, the comment about "failing at the splitting stage" in Rust wasn't true,
since when we split, we ignore empty chunks (e.g. "1--1" parses into
"(1,None),(None,1)" and "None" can't be parsed into an integer).
Finally, the comment about "Rust seems to experience an internal error" is only
true in debug mode, where u32s are bounds-checked at runtime. In release mode,
code expressing the equivalent of this test will error with
`Err(ProtoverError::Unparseable)` because 4294967295 is too large.
Previously, if "Link=1-5" was supported, and you asked protover_all_supported()
(or protover::all_supported() in Rust) if it supported "Link=3-999", the C
version would return "Link=3-999" and the Rust would return "Link=6-999". These
both behave the same now, i.e. both return "Link=6-999".
These were meant to demonstrate old behavior, or old rust behavior.
One of them _should_ work in Rust, but won't because of
implementation details. We'll fix that up later.
The C code and the rust code had different separate integer overflow
bugs here. That suggests that we're better off just forbidding this
pathological case.
Also, add tests for expected behavior on receiving a bad protocol
list in a consensus.
Fixes another part of 25249.
I've refactored these to be a separate function, to avoid tricky
merge conflicts.
Some of these are disabled with "XXXX" comments; they should get
fixed moving forward.
[This is a brute-force method that potentially uses way too much
RAM. Need to rethink this a little. Right now you can DOS an
authority by saying "Foo=1-4294967295".]
