BIP-0174 defines the derivation path being encoded as
"<32-bit uint> <32-bit uint>*"
with the asterisk meaning 0 to n times. Which in turn means that an
empty path is valid, only the key fingerprint is mandatory.
In this commit, we update the top level module to use the newly tagged
sub-modules. Once we remove the circular dependant in these sub-modules,
then we'll no longer have to do things like this.
In this commit, we add a new function `RawTxInTapscriptSignature` that
will be used to generate signatures in the _tapscript_ context. Note
that this differs from top-level taproot as a distinct sighash is used,
and we _always_ accept a root hash to perform the proper tweak.
This was the version tagged that created the new `ecdsa` and `schnorr`
packages. Updating these pinned version lets importers properly use
these packages and build. Things build as is since we use replace
directive to point to the latest version _in the repo_ when we build.
In this commit, we add an initial implementation of BIP-340. Mirroring
the recently added `ecsda` package, we create a new `schnorr` package
with a unique `Signature` type and `ParsePubkey` function. The new
`Signature` type implements the fixed-sized 64-byte signatures, and the
`ParsePubkey` method only accepts pubkeys that are 32-bytes in length,
with an implicit sign byte.
The signing implementation by default, deviates from BIP-340 as it opts
to use rfc6979 deterministic signatures by default, which means callers
don't need to always pass in their own `auxNonce` randomness. A set of
functional arguments allows callers to pass in their own value, which is
the way all the included test vectors function.
The other optional functional argument added is the `FastSign` option
that allows callers to skip the final step of verifying each signature
they generate.
In this commit, we create a new package to house the ECDSA-specific
logic in the new `btcec/v2` pacakge. Thsi c hange is meant to mirror the
structure of the `dcrec` package, as we'll soon slot in our own custom
BIP-340 implementation.
Now that the new `btcutil/v1.0.0` tag has been pushed, we update the new
internal modules to point to the top-level `btcd` repo via replace
directives.
In this commit, we update all the btcutil imports to point to the new
sub-module.
In the same commit, we also modify the recently added `btcutil/go.mod`
file as we need to continue pointing to the _old_ version of btcd, until
we merge this PR and push a new tag.
