2451a217dd test: addmultisigaddress, coverage for script size limits (furszy)
53302a0981 bugfix: addmultisigaddress, add unsupported operation for redeem scripts over 520 bytes (furszy)
9be6065cc0 test: coverage for 16-20 segwit multisig scripts (furszy)
9d9a91c4ea rpc: bugfix, incorrect segwit redeem script size used in signrawtransactionwithkey (furszy)
0c9fedfc45 fix incorrect multisig redeem script size limit for segwit (furszy)
f7a173b578 test: rpc_createmultisig, decouple 'test_sortedmulti_descriptors_bip67' (furszy)
4f33dbd8f8 test: rpc_createmultisig, decouple 'test_mixing_uncompressed_and_compressed_keys' (furszy)
25a81705d3 test: rpc_createmultisig, remove unnecessary checkbalances() (furszy)
b5a3289433 test: refactor, multiple cleanups in rpc_createmultisig.py (furszy)
3635d43268 test: rpc_createmultisig, remove manual wallet initialization (furszy)
Pull request description:
Fixing https://github.com/bitcoin/bitcoin/issues/28250#issuecomment-1674830104 and more.
Currently, redeem scripts longer than 520 bytes, which are technically valid under segwit rules, have flaws in the following processes:
1) The multisig creation process fails to deduce the output descriptor, resulting in the generation of an incorrect descriptor. Additionally, the accompanying user warning is also inaccurate.
2) The `signrawtransactionwithkey` RPC command fail to sign them.
3) The legacy wallet `addmultisigaddress` wrongly discards them.
The issue arises because most of these flows are utilizing the legacy spkm keystore, which imposes
the [p2sh max redeem script size rule](ded6873340/src/script/signingprovider.cpp (L160)) on all scripts. Which blocks segwit redeem scripts longer than
the max element size in all the previously mentioned processes (`createmultisig`, `addmultisigaddress`, and
`signrawtransactionwithkey`).
This PR fixes the problem, enabling the creation of multisig output descriptors involving more than 15 keys and
allowing the signing of these scripts, along with other post-segwit redeem scripts that surpass the 520-byte
p2sh limit.
Important note:
Instead of adding support for these longer redeem scripts in the legacy wallet, an "unsupported operation"
error has been added. The reasons behind this decision are:
1) The introduction of this feature brings about a compatibility-breaking change that requires downgrade
protection; older wallets would be unable to interact with these "new" legacy wallets.
2) Considering the ongoing deprecation of the legacy spkm, this issue provides another compelling
reason to transition towards descriptors.
Testing notes:
To easily verify each of the fixes, I decoupled the tests into standalone commits. So they can be
cherry-picked on top of master. Where `rpc_createmultisig.py` (with and without the `--legacy-wallet`
arg) will fail without the bugs fixes commits.
Extra note:
The initial commits improves the `rpc_createmultisig.py` test in many ways. I found this test very
antiquated, screaming for an update and cleanup.
ACKs for top commit:
pinheadmz:
ACK 2451a217dd
theStack:
Code-review ACK 2451a217dd
achow101:
ACK 2451a217dd
Tree-SHA512: 71794533cbd46b3a1079fb4e9d190d3ea3b615de0cbfa443466e14f05e4616ca90e12ce2bf07113515ea8113e64a560ad572bb9ea9d4835b6fb67b6ae596167f
The process currently fails to sign redeem scripts that are longer than
520 bytes. Even when it shouldn't. The 520 bytes redeem scripts limit
is a legacy p2sh rule, and not a segwit limitation.
Segwit redeem scripts are not restricted by the script item size limit.
The reason why this occurs, is the usage of the same keystore used by
the legacy spkm. Which contains blockage for any redeem scripts longer
than the script item size limit.
Move the parsing and validation out of `AddOutputs` into its own function,
`ParseOutputs`. This allows us to re-use this logic in `ParseRecipients` in a
later commit, where the code is currently duplicated.
The new `ParseOutputs` function returns a CTxDestination,CAmount tuples.
This allows the caller to then translate the validated outputs into
either CRecipients or CTxOuts.
Move the univalue formatting logic out of AddOutputs and into its own function,
`NormalizeOutputs`. This allows us to re-use this logic in later commits.
Currently, if -validatepegin is given, and block validation can't proceed
because the parent chain is not synced, we mark the block invalid and put
it in a queue to be "revalidated" later. Unfortunately, marking a block
invalid has downstream consequences, in particular causing descendant blocks
to be marked invalid, which are not currently fixed by the queue.
Instead, we'll use a different strategy: if the mainchain daemon isn't
sufficiently synced to validate a block, we will "stall" connecting that
block to the chain, and have ActivateBestChain simply keep the tip at the
previous block until we're ready.
We can still download and validate (partly) blocks past this point while
we're waiting. They will be connected once the parent chain daemon catches
up.
This forward-ports the new Taproot sighash but does not fix a couple
22-blocked TODOs related to the MissingDataBehavior enum. Should be fixed
in a followup commit.
One nontrivial change I had to make was feeding the genesis hash to SignTransaction
(the "global" one in script/sign.cpp) so that it could correctly compute
the sighash at signing time.
Surprisingly easy to do. Almost all of the diff resolution was mechanically
* replacing boost::variant with std::variant
* replacing Optional with std::optional
* then replacing `nullopt` with `std::nullopt`
* updating the RPC functions for the new RPCArg::Default type
* update the tests/ directory to make new (since 22) tests use arrays for
createrawtransaction outputs
* other ad-hoc changes to function parameters etc (not too many of these)
I had to "really" change the code in PrecomputePSBTData, which was introduced
in 22.0 and affected by PSET, but this function was like 8 lines long so it
was easy.
Reviewing the diff may be a bit difficult because of the mix of mechanical
changes and ad-hoc things. Probably the most straightforward thing to do
is to redo the merge, `sed -i` to fix the boost::variant and Optional stuff,
then diff the remaining conflicts against this commit.
TODO: grep for `blindpsbt` and you will see that this RPC is still referenced
in documentation and help text even though it was deleted. Need to fix this
in 0.21 in a separate PR.
Instead of having an output_assets argument to createpsbt,
createrawtransaction, and walletcreatefundedpsbt, move the asset
specification into the outputs array itself. This also removes the
backwards compatibility of using a dict for outputs in createrawtransaction.