24d6f62603 Use explicit u8 when assigning a byte slice (junderw)
Pull request description:
Is there a way to tell the compiler to not allow `[0; 64]` and require that either the type is explicitly given to the variable, or that each member uses explicit `0u8` notation?
I noticed the usage was a mix of explicit and implicit, so I changed all to explicit.
ACKs for top commit:
apoelstra:
ACK 24d6f62603
Tree-SHA512: f7796dcc3ae240983257bef0f25bd0df741943f75d86e9bca7c45076af179d96ce213bd9c339a01f721f7dc9b96a0a4a56ef2cf44339f4c91d208103b7659d9f
This reduces the usage of real cryptography in --cfg=fuzzing,
specifically replacing the secret->public key derivation with a
simple copy and ECDH with XOR of the public and private parts
(plus a stream of 1s to make a test pass that expected non-0
output).
It leaves secret tweak addition/multiplication as-is.
It also changes the context creation to over-allocate and store
the context flags at the end of the context buffer, allowing us
to easily test context flags in each function.
While it would be nice to have something fancier (eg XOR-based),
its not immediately obvious how to accomplish this, and better to
fix the issues I have than spend too much time on it.
Fixes#271.
This partially reverts b811ec133a
In the next commit the secret->public key derivation in fuzzing cfg
is changed to be simpler, as well as the validity rules of public
keys relaxed.
This adds a new test to ensure random keys can be added, not just
the hard-coded keys test that exists today.
Currently we are misusing `map` on an iterator to loop `n` times,
additionally the assertion is pointless. Use a for loop and assert
against the length of the set.
Instead of repeating ourselves in defining one big test for the wasm
target, we can override the `test` attribute with the `wasm-bindgen-test`
one and therefore automatically run all (supported) tests in wasm.
Unfortunately, wasm doesn't support catching panics yet which means we
have to disable the `test_panic_raw_ctx` test.
The interfaces for negate should always returns 1 as mentioned secp256k1.h L574, L563.
But in the future it might return 0 if the seckey or pubkey is invalid, but our type system doesn't allow that to ever happen.
Turns out you cannot initialize constant SecretKeys in any way; these
two constants should cover most sane use cases (other good choices
are the SECG generator and the Alpha CT generator, but these will
wait for a major CT-supporting upgrade, unless demand for them appears.)
This should be a major version number since I changed public constants
in the ffi module. I'm not doing so as the invariant "will the constants
be meaningful to the underlying library" has not changed.
In general this library's version numbers do not map well to the
underlying library, which is as-yet not versioned at all, so users
need to always be running "the lastest" rust-secp256k1 anyway, and
semantic versioning can't really be used meaninfully. So this is a
bit of a judgement call.
If you try to call PublicKey::from_secret() key with an incapable context it will
now return an error. Before it would pass through to the underlying library which
would terminate the process, something we strive to never expose.
Also change the from_ffi functions on various types to impl's of From to be more
Rustic. We cannot change the from_slice functions because they have error returns.
Also add a Secp256k1::without_caps() function which creates a capability-less
context. I find myself using this in so many places downstream that it seems
appropriate.
There are a lot of cases in rust-bitcoin where we need a `Secp256k1`
which doesn't need any signing or verification capabilities, only
checking the validity of various objects. We can get away with a bare
context (i.e. no precomputation) which can be cheaply created on demand,
avoiding the need to pass around references to Secp256k1 objects everywhere.
API break because the following functions can now fail (given an insufficiently
capable context) and therefore now return a Result:
Secp256k1::generate_keypair
Secp256k1::sign
Secp256k1::sign_compact
The Rng was only used for key generation, and for BIP32 users not even then;
thus hauling around a Rng is a waste of space in addition to causing a
massive amount of syntactic noise. For example rust-bitcoin almost always
uses `()` as the Rng; having `Secp256k1` default to a `Secp256k1<Fortuna>`
then means even more syntactic noise, rather than less.
Now key generation functions take a Rng as a parameter, and the rest can
forget about having a Rng. This also means that the Secp256k1 context
never needs a mutable reference and can be easily put into an Arc if so
desired.
This comes with a couple bugfixes and the following API changes:
- Secp256k1::sign and ::sign_compact no longer return Result;
it is impossible to trigger their failure modes with safe
code since the `Message` and `SecretKey` types validate when
they are created.
- constants::MAX_COMPACT_SIGNATURE_SIZE loses the MAX_; signatures
are always constant size
- the Debug output for everything is now hex-encoded rather than
being a list of base-10 ints. It's just easier to read this way.
kcov v26 now reports 100% test coverage; however, this does not
guarantee that test coverage is actually complete. Patches are
always welcome for improved unit tests.
Dr Maxim Orlovsky
Thomas Eizinger
Andrew Poelstra
junderw
Tibo-lg
Matt Corallo
sanket1729
Elichai Turkel
Tobin Harding
Justin Moon
Kohei Taniguchi
Rodolfo Araujo
Steven Roose
Jonas Nick
Tim Ruffing
Aleksei Sidorov
François Garillot
Pierre Krieger
Tim Ruffing
Peter Todd
Christian Nyumbayire
Dawid Ciężarkiewicz