Currently we have a few things mixed up in the feature gating of
`hashes`.
Observe that:
- `io::Write` is not related to allocation.
- "std" should be able to enable "alloc".
Improve feature gating by doing:
- Enable "alloc" from "std" and simplify `cfg` codebase wide.
- Enable "internals/alloc" from "alloc".
- Fix feature gating to use the minimal requirement i.e., "alloc".
Remove `FromHex` from hash and script types
- Remove the `FromHex` implementation from hash types and `ScriptBuf`
- Remove the `FromStr` implementation from `ScriptBuf` because it does not
roundtrip with `Display`.
- Implement a method `from_hex` on `ScriptBuf`.
- Implement `FromStr` on hash types using a fixed size array.
This leaves `FromHex` implementations only on `Vec` and fixed size arrays.
It is easier to maintain code if macros use the fully qualified path to
types and functions instead of relying on code that uses the macro to
import said type or function.
We have old Rust 1.29 error handling code still in `hashes`. Implement
`std::error::Error` for the `hex::Error` and `error::Error` types in
line with "modern" Rust 1.41.1 error handling.
Implement `AsRef<[u8; X]>` for hash types including wrapped hash types.
Doing so means at times the compiler can no longer infer the type because we have
`AsRef<[u8]` implemented also but we can use `into_inner` and `as_inner`
to get the inner array if needed.
The `HexWriter` is not used any more since we added the new hex code in
internals for fast hex encoding.
While we are removing the benches for `HexWriter` also remove the last
remaining bench for writing using `Display` because this is not the
correct place for that code - its trivial to re add later in the correct
module.
The `ToHex` trait was replaced by either simple `Display`/`LowerHex`
where appropriate or `DisplayHex` from `bitcoin_internals` which is
faster.
This change replaces the usages and removes the trait.
411174c391 Add fuzz target for sha512_256 (Calvin Kim)
31fc1f8638 Add support for sha512/256 (Calvin Kim)
15b5af1117 Export sha512::HashEngine fields/function within the crate (Calvin Kim)
Pull request description:
Adds a new file named `sha512_256.rs` that implements the `sha512/256` hash. This was needed as a part of https://github.com/rust-bitcoin/rust-bitcoin/discussions/1318 to drop the `sha2` dependency.
All the actual hashing code is exactly the same as `sha512.rs`, minus the initial constants and the use of `hash_type!` macro. Some unit tests were added from wikipedia (for the "" input) and the rest were from the Go standard library's tests for sha512_256.
Benchmarks on my Ryzen 3600 machine show that it is faster than sha256.
```
test sha256::benches::sha256_10 ... bench: 37 ns/iter (+/- 0) = 270 MB/s
test sha256::benches::sha256_1k ... bench: 3,338 ns/iter (+/- 24) = 306 MB/s
test sha256::benches::sha256_64k ... bench: 213,605 ns/iter (+/- 1,806) = 306 MB/s
test sha512_256::benches::sha512_256_10 ... bench: 27 ns/iter (+/- 1) = 370 MB/s
test sha512_256::benches::sha512_256_1k ... bench: 2,196 ns/iter (+/- 12) = 466 MB/s
test sha512_256::benches::sha512_256_64k ... bench: 140,552 ns/iter (+/- 777) = 466 MB/s
```
One caveat is that I could not get hongfuzz to build locally so I couldn't test the fuzz on my machine. I ended up only testing through the CI for the fuzz tests.
I thought adding a completely separate file was the easiest and the most straightforward way of implementing it. I'm very much open to changing the implementation if you guys don't think this is the right direction.
ACKs for top commit:
sanket1729:
ACK 411174c391. Reviwed range diff from 43feb9ea7b282d9119708a27fa7a1c7412d1386a that I had ACked
apoelstra:
ACK 411174c391
Tree-SHA512: 98298a7c177cbb616bfbc02cec5c5860f10204df8275cc9f1e4ea07333b901095e574fbc3fe0a03375e0d321a1579e2c2023a5c14addd863e10cc927f155710c
3e520f9094 Use hex from internals rather than hashes (Martin Habovstiak)
Pull request description:
`bitcoin-internals` contains a more performant implementation of hex encoding than what `bitcoin_hashes` uses internally. This switches the implementations for formatting trait implementations as a step towards moving over completely.
The public macros are also changed to delegate to inner type which is technically a breaking change but we will break the API anyway and the consuers should only call the macro on the actual hash newtypes where the inner types already have the appropriate implementations.
Apart from removing reliance on internal hex from public API this reduces duplicated code generated and compiled. E.g. if you created 10 hash newtypes of SHA256 the formatting implementation would be instantiated 11 times despite being the same.
To do all this some other changes were required to the hex infrastructure. Mainly modifying `put_bytes` to accept iterator (so that `iter().rev()` can be used) and adding a new `DisplayArray` type. The iterator idea was invented by Tobin C. Harding, this commit just adds a bound check and generalizes over `u8` and `&u8` returning iterators.
While it may seem that `DisplayByteSlice` would suffice it'd create and initialize a large array even for small arrays wasting performance. Knowing the exact length `DisplayArray` fixes this.
Another part of refactoring is changing from returning `impl Display` to return `impl LowerHex + UpperHex`. This makes selecting casing less annoying since the consumer no longer needs to import `Case` without cluttering the API with convenience methods.
ACKs for top commit:
tcharding:
ACK 3e520f9094
apoelstra:
ACK 3e520f9094
Tree-SHA512: 62988cec17550ed35990386e572c0d32dc7107e1c36b7c9099080747e15167e6d66497fb300178afbd22481c0360a6b7a1228fd09402d4ce5d295a8594c02aa6
5a2a37d4be Allow dead_code/unused_imports when fuzzing (Tobin C. Harding)
Pull request description:
Littering the codebase with `#[cfg(not(fuzzing))]` is a bit messy just to quieten the linter during fuzzing. Instead just globally allow.
Done while debugging #1409
ACKs for top commit:
sanket1729:
ACK 5a2a37d4be
apoelstra:
ACK 5a2a37d4be
Tree-SHA512: fb84215a2b00ad6d3321b2781ba285af513ff8fd413c0997045a41c4f23028d2ef0fdf083839289d0c5108c990aa66bdae4430ad3ef32881eac5324b2e881b3b
`bitcoin-internals` contains a more performant implementation of hex
encoding than what `bitcoin_hashes` uses internally. This switches the
implementations for formatting trait implementations as a step towards
moving over completely.
The public macros are also changed to delegate to inner type which is
technically a breaking change but we will break the API anyway and the
consuers should only call the macro on the actual hash newtypes where
the inner types already have the appropriate implementations.
Apart from removing reliance on internal hex from public API this
reduces duplicated code generated and compiled. E.g. if you created 10
hash newtypes of SHA256 the formatting implementation would be
instantiated 11 times despite being the same.
To do all this some other changes were required to the hex
infrastructure. Mainly modifying `put_bytes` to accept iterator (so that
`iter().rev()` can be used) and adding a new `DisplayArray` type. The
iterator idea was invented by Tobin C. Harding, this commit just adds a
bound check and generalizes over `u8` and `&u8` returning iterators.
While it may seem that `DisplayByteSlice` would suffice it'd create and
initialize a large array even for small arrays wasting performance.
Knowing the exact length `DisplayArray` fixes this.
Another part of refactoring is changing from returning `impl Display` to
return `impl LowerHex + UpperHex`. This makes selecting casing less
annoying since the consumer no longer needs to import `Case` without
cluttering the API with convenience methods.
Currently we implement `Deref` for hashes. From the docs [0]
> Deref should only be implemented for smart pointers to avoid confusion
Furthermore because we implement `Deref` as well as implement
`internals::hex::display::DisplayHex` for slices hashes get coerced into
slices and `to_lower_hex_string` can be called on them, this is
incorrect because `DisplayHex` does not account for hashes that display
backwards so we end up with the wrong string.
[0] https://doc.rust-lang.org/std/ops/trait.Deref.html
Recently clippy was updated and now new warnings are generated for the
`hashes` crate.
Clippy emits 3 warnings of form:
warning: this expression borrows a value the compiler would automatically borrow
As suggested, remove the explicit borrow.
We would like to bring the `bitcoin_hashes` crate into the
`rust-bitcoin` repository.
Import `bitcoin_hashes` into `rust-bitocin/hashes`, doing so looses all
the commit history from the original crate but if we archive the
original repository then the history will be preserved. We maintain the
same version number obviously and in the changelog we note the change of
repository.
Commit hash that was tip of `bitcoin_hashes` at time of import:
commit 54c16249e06cc6b7870c7fc07d90f489d82647c7
Includes making `embedded` and `fuzzing` per-crate i.e., move them into
`bitcoin` as hashes includes these also.
NOTE: Does _not_ enable fuzzing for `hashes` in CI.
Notes on CI:
Attempts to merge in the github actions from the hashes crate however reduces
coverage by not running hashes tests for beta toolchain. Some additional
work could be done to improve the CI to increase efficiency without
reducing coverage. Leaving for another day.
Harshil Jani
Tobin C. Harding
Martin Habovstiak
Andrew Poelstra
Calvin Kim
sanket1729