Previous changes enabled passing the string used as a tag into
`sha256t_hash_newtype!` macro rather than hard-coding midstate. This
commit takes advantage of it and replaces the hard-coded values with
compile-time executed (`const`) hashing.
The Rust API guidelines state that macros should be evocative of the
output, which is a sensible recommendation. We already had this for
`hash_newtype!` macro but didn't for sha256t version.
This changes the macro to have this syntax:
```rust
sha256t_hash_newtype! {
// Order of these structs is fixed.
/// Optional documentation details here. Summary is auto-generated.
/*pub*/ struct Tag = raw(MIDSTATE_BYTES, LEN);
/// Documentation here
#[hash_newtype(forward)] // optional, default is backward
/*pub*/ struct HashType(/* attributes allowed here */ _);
}
```
Closes#1427
If we use `#![cfg_attr(docsrs, feature(doc_auto_cfg))]` instead of
`#![cfg_attr(docsrs, feature(doc_cfg))]` we no longer need to manually
mark types with `#[cfg_attr(docsrs, doc(cfg(feature = "std")))]`.
Sweeeeeet.
Currently we have an associated type on hash types `Inner` with
accompanying methods `into_inner`, `from_inner`, `as_inner`. Also, we
provide a way to create new wrapped hash types. The use of 'inner'
becomes ambiguous with the addition of wrapped types because the inner
could be the inner hash type or the `Inner` byte array of the inner
wrapped hash type.
In an effort to make the API more clear and uniform do the following:
- Rename `Inner` -> `Bytes`
- Rename `*_inner` -> `*_byte_array`
- Rename the inner hash to/from methods to `*_raw_hash`
Correct method prefix `into_` -> `to_` because theses methods convert
owned `Copy` types.
Add the trait Bound `Copy` to the `Bytes` type because we rely on this
trait bound for the conversion methods to be correctly named according
to convention.
Because of the dependency hole created by `secp256k1` this patch changes
the secp dependency to a git tag dependency that includes changes to the
hashes calls required so that we can get green lights on CI in this
repo.
The API guidelines say macro input should be evocative of the output.
`hash_newtype` didn't have this property.
This change makes it look exactly like the resulting struct, `$len`
parameter was removed since it's not needed, reversing is controlled
using an attribute. The macro is also better documented and ready to be
extended in the future.
The tagged SHA256 newtype is not yet modified because it has a more
complicated input parameters.
Closes#1648
"schnorr" is a dirty word; the current `schnorr` module defines a
`Signature` that includes a sighash type, this sighash type is a bitcoin
specific construct related to taproot. Therefore the `Signature` is
better named `taproot::Signature`. Note also that the usage of `schnorr`
in `secp256k1` is probably justified because the
`secp256::schnorr::Signature` is just doing the crypto.
While we are at it, update docs and error messages to use "taproot"
instead of "schnorr". Also change function names and identifiers that
use "schnorr".
Currently we have `TapSighash` that is used for taproot sighashes but
for non-taproot sighashes we use `hash_types::Sighash`. We can improve
the API by creating a `LegacySighash`, and `SegwitV0Sighash`.
Copy the original `Sighash` macro calls to create the two new types in
the `sighash` module.
While we are at it, put the `TapSighash` and `TapSighashTag` into the
`sighash` module also.
There is never any use for the `sighash` module unless one is signing,
which requires the `crypto` module. The `sighash` module should
therefore live in the `crypto` module. This is not an API breaking
change because we reexport it at the crate root.
yancy
Martin Habovstiak
Tobin C. Harding