Also re-`static`'d a method in src/script/standard.cpp which we had made globally
visible for some historical reason, but which I noticed diffing that file against
upstream.
I really like this PR, but it wound up being pretty nontrivial to merge.
The crux is that it pulls PSBT signing logic into scriptpubkey manager,
which is where it belongs, but for us this means reasoning about pegins
inside script/sign.cpp.
However, sign.cpp is part of libbitcoin_common, which does not include
anything for reasoning about PoW or RPC (lol) or anything heavy about
that. This means that some pegin validation had to remain split between
the wallet/rpc layer and sign.cpp. I added a new file script/pegins.cpp
which has the (one) method we actually need in sign.cpp.
Aside from that, this diff is very large but is mostly just moving our
code changes to wallet/psbtwallet.* into wallet/wallet.* where those
functions now live. As far as review, it's probably not worthwhile to
spend too much too much time on this since it's going to be change
again in #16528 and others. The test coverage is pretty extensive.
This fixes a segfault I introduced in 981df590811 (#17371) a couple hundred PRs
ago, where we might out-of-bounds access the vout arrray of a non_witness_utxo
transaction in a PSBT.
This logic should probably be refactored after the rebase -- we sift through
the non_witness_utxos to find a scriptpubkey, which we use to get a wallet
provider, so we can pass this to SignPSBTInput, which then repeats the same
logic (for its own reasons, and without the segfault bug)....and we aren't
even calling SignPSBTInput for signing reasons! It has something to do with
blinding.
To resolve the `ConstructTransaction` conflict I reverted to the existing code
then manually applied the diff (it adds a parameter then adds a giant pile of
code to the input loop).
FIXME: we disable standardness checks for the non-PAK node in the PAK tests.
This is because of a bug in Elements which causes non-PAK nodes to reject
pegouts for standardness reasons. Need to fix it after the rebase.
Also uncommented a bunch of PSBT functional tests (had to add a fee output
to one transaction, update `find_output` to skip CT outputs, and change two
constant checks at the end of the commented-out section).
