These helpers haven't been used in production code since segwit was
merged more than eight years ago (see commit 605e8473, PR #8149),
so it seems appropriate to move them to the test utils module.
Can be reviewed via `--color-moved=dimmed-zebra`.
These outputs are called anchors, and allow
key-less anchor spends which are vsize-minimized
versus keyed anchors which require larger outputs
when creating and inputs when spending.
`ProduceSignature` already calls `VerifyScript` internally as last step in
order to check whether the signature data is complete. If and only if that is
the case, the `complete` field of the `SignatureData` is set accordingly and
there is no need then to verify the script after again, as we already know that
it would succeed.
This leads to a rough ~20% speed-up for `SignTransaction` for single-input
ECDSA or Taproot inputs, according to the `SignTransaction{ECDSA,Taproot}`
benchmarks.
The script provided for signature might be externally provided, for
instance by way of 'finalizepsbt'. Therefore the script might be
ill-crafted, so don't assume pubkeys are always 32 bytes.
Thanks to Niklas for finding this.
We make the Satisfier a base in which to store the common methods
between the Tapscript and P2WSH satisfier, and from which they both
inherit.
A field is added to SignatureData to be able to satisfy pkh() under
Tapscript context (to get the pubkey hash preimage) without wallet data.
For instance in `finalizepsbt` RPC. See also the next commits for a
functional test that exercises this.
We are going to introduce Tapscript support in Miniscript, for which
some of Miniscript rules and properties change (new or modified
fragments, different typing rules, different resources consumption, ..).
6c7a17a8e0 psbt: support externally provided preimages for Miniscript satisfaction (Antoine Poinsot)
840a396029 qa: add a "smart" Miniscript fuzz target (Antoine Poinsot)
17e3547241 qa: add a fuzz target generating random nodes from a binary encoding (Antoine Poinsot)
611e12502a qa: functional test Miniscript signing with key and timelocks (Antoine Poinsot)
d57b7f2021 refactor: make descriptors in Miniscript functional test more readable (Antoine Poinsot)
0a8fc9e200 wallet: check solvability using descriptor in AvailableCoins (Antoine Poinsot)
560e62b1e2 script/sign: signing support for Miniscripts with hash preimage challenges (Antoine Poinsot)
a2f81b6a8f script/sign: signing support for Miniscript with timelocks (Antoine Poinsot)
61c6d1a844 script/sign: basic signing support for Miniscript descriptors (Antoine Poinsot)
4242c1c521 Align 'e' property of or_d and andor with website spec (Pieter Wuille)
f5deb41780 Various additional explanations of the satisfaction logic from Pieter (Pieter Wuille)
22c5b00345 miniscript: satisfaction support (Antoine Poinsot)
Pull request description:
This makes the Miniscript descriptors solvable.
Note this introduces signing support for much more complex scripts than the wallet was previously able to solve, and the whole tooling isn't provided for a complete Miniscript integration in the wallet. Particularly, the PSBT<->Miniscript integration isn't entirely covered in this PR.
ACKs for top commit:
achow101:
ACK 6c7a17a8e0
sipa:
utACK 6c7a17a8e0 (to the extent that it's not my own code).
Tree-SHA512: a71ec002aaf66bd429012caa338fc58384067bcd2f453a46e21d381ed1bacc8e57afb9db57c0fb4bf40de43b30808815e9ebc0ae1fbd9e61df0e7b91a17771cc
Try to solve a script using the Miniscript satisfier if the legacy
solver fails under P2WSH context. Only solve public key and public key
hash challenges for now.
We don't entirely replace the raw solver and especially rule out trying to
solve CHECKMULTISIG-based multisigs with the Miniscript satisfier since
some features, such as the transaction input combiner, rely on the
specific behaviour of the former.
