rust-bitcoin

Update the API text files

hashes: Add drain_to_engine function

Add a function that pairs with `encode_to_engine`. This is similar to
the APIs `encode_to_writer`/`drain_to_writer` in other crates.

Note, use one level of path on the `Encoder` to be uniform with the
code in `encode_to_engine`.

ci: Change encodable coverage to check for Encode trait

The Encodable trait was recently renamed to Encode, but this script
was not similarly updated. As such, the CI now fails due to an
incorrect docs file path.

Change Encodable to Encode in encodable coverage check to track new
trait name.

ci: clean up github disk bloat

fuzz: add max_total_time option to fuzz.sh

bitcoin: cut down on exact_features test matrixes

The Github CI runner is timing out when running all the feature sets
on the older MSRV compiler. The current list of exact_features in the
bitcoin crate was a conserative "include everything" when we switched
over to cargo-rbmt. This cuts it down ~50% and focuses on core
interactions we want to always cover. This puts more responsibilites on
cargo-rbmt's random feature subsets it runs on every commit.

ci: revert to local action for setup-rbmt

Github Actions doesn't allow the uses key to be set by a runtime value,
which means a separate rbmt version needs to be managed just for the
shared action. Given how little this action does, easier to just copy
paste it and avoid the confusion.

ci: do not run tests on the nightly toolchain

Discussed elsewhere, but these are relatively expensive, requiring a bunch
of artifacts to be built for the specific nightly toolchain, and don't
provide much more signal than the lint run.

Introduce CI action to enforce encodable fuzzing

With the introduction of the Encodable differential fuzz target, it's
important to ensure that all new implementations of Encodable types
are compared against existing implementations from bitcoin 0.32.

Add Encodable-coverage action to check compare_consensus_encoding
target for inclusion of all Encodable types on branch and bitcoin 0.32.

Assisted-by: Claude Opus 4.5

Add fuzz target comparing consensus encoding to bitcoin 0.32

Since bitcoin 0.32, consensus encoding has been rebuilt from the ground
up with the consensus_encoding crate. In order to confirm that it
functions identically to the original encoding implementations, the
two should be differentially fuzzed.

Introduce a fuzz target that compares encodings using serialize from
bitcoin 0.32 against encode_to_vec from consensus_encoding.

crypto: Remove unused test from ecdsa

In ecdsa, the write_serialized_signature test was used to test the
serialize_to_writer method on the ecdsa::Signature. Since this was
removed as part of the bitcoin-io dep removal, the test should also
be removed.

Remove write_serialized_signature test case from ecdsa tests module.

Re-name consensus_encoding main traits

When we did the first implementation of the `consensus_encoding` crate
we used the same names for the public traits as the old encoding code.

In hindsight we should have used the more Rusty terms `Encode` and
`Decode` instead of `Encodable` and `Decodable`.

Bonus points the new names are easier to spell.

Do trivial-ish rename. Leave the `EncodableBytesIter` as is because
the fix to it is non-trivial. Leave the old encoding traits as they
are because they are destined for the grave very soon anyways.

Update the API text files

Enable multiple tests in single macro call

Instead of calling the macro to define each test in a single call add
support for multiple tests in one call. Makes the code more terse at
the cost of macro complexity. Also we want to exclude these from the
formatter so a single macro call is way better.

Requires splitting one macro into three and removing the flag at
the front (display, lower, upper).

crypto: Bump version to 0.2.0

Bump the `crypto` version. Update the dep in `bitcoin` and add an
explicit version number in `taproot-primitives`.

In preparation add a changelog entry, bump the version number, and
update the lock files.

Delete psbt module

In #6055 we deprecated the `psbt` module on the `0.32.x` branch. Now
we can delete it from master.

### Context

Development of the PSBT has moved to a separate crate. Hosted on the
new Forgejo instance at:

https://git.rust-bitcoin.org/rust-bitcoin/rust-psbt

Crate name is `psbt-v2` because it has initial support for PSBTv2. The
crate also includes all code from the `0.32.x` branch (as well as
miniscript code). In other words the crate is a drop in replacement
for the `Psbt` type and its functionality.

During release of `psbt-v2 v0.3.0` we attempted to ensure feature
parity with `0.32.x` since the actual migration was done a while back.

The road map for dev of `psbt-v2` is loosely:

- Improve PSBTv2 stuff
- Continue work on supporting Silent Payments
- Use crate as a test bed for the process of upgrade of `bitcoin 0.32.x`


Exact strategy of the last point is being worked on. We are
investigating creating a bunch of step-by-step releases to help the
process. To prove (and develop) the process we plan on using:

- miniscript
- psbt-v2
- corepc

fuzz: Migrate p2p fuzz targets to new encoding

p2p: remove deprecated encoders in V1NetworkMessage constructor

`payload.consensus_encode()` is deprecated. Replace with
newer sans/IO `hashes::encode_to_engine()`.

Also, updated the doc comment now that encode no longer has a panic
path.

p2p: return count of bytes hashed sha2_checksum()

When computing the message body from the header, its required to know
the number of bytes. In order to do so, keep track of the number of
bytes hashed.

Implement P2WPKH & P2WSH output spend script

`p2sh_p2wpkh` implements the scriptSig required to spend a P2SH-P2WPKH
output, for the spend address, by appending witness version and the
witness program to the output script, for the P2SH input script to unlock.

`p2sh_p2wsh` implements the scriptSig required to spend P2SH-P2WSH
output, for the spend address, appending the witness version and the
32-byte SHA256 hash of the witness script, to be executed alongside
the P2SH input script.

Implement p2wsh Witness constructor

`p2wsh` constructs a witness inpust script required by a P2WSH output
script, the constructor appends all conditions that should be satisfied
by the output script to redeem the input witness script.

Introduce check to re-exports CI for error types

With the move to error submodules, we should move towards a policy for
error access. Specifically, for any foo::error::FooError, there should
also exist a foo::FooError. This has already been implemented in units
and primitives, but should also be enforced by CI in the case of new
errors.

Add check error reexport script and add to check re-exports CI action.

Assisted by Claude Opus 4.6.

hashes: Add x86 AVX2 8-way dispatch

add dispatcher that handles 8-way

hashes: fold 8-way AVX2 SHA256d into round! macro

use a round! macro to cut ~1060 lines from the unrolled version.
each round becomes a single round!(...) call that almost matches
Core's Transform_8way line-by-line, so it's easy to compare and
review against sha256_avx2.cpp.

refactor, no behavior change.

hashes: Add 8-way AVX2 SHA256d for 64-byte input

add the three transforms for sha256(sha256(64_bytes)) using AVX2
SIMD.

AVX2 uses 256-bit registers, so we can pack eight 32-bit words into
each register and compute 8 independent hashes in parallel with a
single SIMD op.

- Transforms 1 & 2 compute the inner `sha256(64_bytes)`.
- Transform 3 computes sha256(output_of_T1_and_T2).

rounds are fully unrolled (we will use a round! macro to fold them
in the next patch).