This is the 43-commit descriptor wallet PR. It was remarkably easy to merge, given
its magnitude. With this commit Elements supports importing Bitcoin descriptors
and deriving (Bitcoin) addresses, though of course it does not support blinding
yet. That is a post-rebase project.
The material changes were:
1. Changing constants in the tests (super annoying but nothing surprising)
2. Adding a missing "skip if this coin is not ours" check in src/script/sign.cpp
which was causing us to erroneously remove existing witnesses from transactions.
This wasn't a problem before this commit since we would only ask specific
scriptpubkeymans to sign, and we'd never ask any to sign inputs we didn't
own. Andy simplified the logic here to always try every scriptpubkeyman,
which means they have to play a bit more nicely with each other.
Other than that, this was a big diff with many conflicts but literally all of
them were "we both added code" and the resolution was to take both sides.
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.
Moved GetOnlinePakKey to the scriptpubkey manager; the other blinding
stuff remains in the CWallet. At some point after the rebase we should
consider whether there's a better separation to be had between the PAK
related stuff now that we have wallet boxes.
This PR associates OutputType::BECH32 to PAK online keys, where before we
were able to directly access keys from the keypool. In a future refactoring
we should give PAK keys their own output type (and own scriptpubkey manager)
so that the wallet won't accept payments "to the PAK key".
Also changes `ReserveDestination::SetBlindingPubKey` to use a visitor pattern
to apply a blinding pubkey to a destination directly, rather than using the
old hacky method of regenerating the destination by pulling its key (which
is no longer contained in the class) out and giving it to a new constructor.
This was a long-overdue refactoring and the minimal-diff way to get the code
compiling (and it's not bad, maybe 10LOC to add a new visitor class) but
nonetheless I apologize for sticking this into a merge commit.
This is the start of some nontrivial wallet refactoring by achow. See
https://github.com/bitcoin-core/bitcoin-devwiki/wiki/Wallet-Class-Structure-Changes
for a high-level design.
This PR moves some stuff out of CWallet into a dummy "box" LegacyScriptPubKeyMan
which is (currently) very tightly coulped to CWallet. Because of the coupling there
are currently null-checks that cannot fail, things which assume non-nullness which
will eventually be wrong, and a plethora of currently-equivalent ways to get from
a CWallet to a provider or back.
Our approach is basically to ignore the refactoring; leave the blinding key stuff
in CWallet and have it call into the wallet's provider when we are obtaining the
underlying keys.
Later, probably in a post-rebase PR, we should rethink how we manage blinding keys
to more closely match Core's "all keys go into providers" model.
Common errors and warnings should be translated when displayed in the
GUI, but not translated when displayed elsewhere. The wallet method
CreateWalletFromFile does not know its caller, so this commit changes it
to return a bilingual_str to the caller.
Internally, a GetSigningProvider function is introduced which allows for
some private keys to be optionally included. This can be called with a
script as the argument (i.e. a scriptPubKey from our wallet when we are
signing) or with a pubkey. In order to know what index to expand the
private keys for that pubkey, we need to also cache all of the pubkeys
involved when we expand the descriptor. So SetCache and TopUp are
updated to do this too.
Not all ScriptPubKeyMans will be able to provide private keys,
but pubkeys and scripts should be. So only provide public-only
SigningProviders, i.e. ones that can help with Solving.
Instead of fetching a SigningProvider from ScriptPubKeyMan in order
to fill and sign the keys and scripts for a PSBT, just pass that
PSBT to a new FillPSBT function that does all that for us.
CWallet::CanGetAddresses() is used to check whether the wallet has available or is able to produce keys for addresses. It uses the ScriptPubKeyMan::CanGetAddresses(), which in turn uses the const KeypoolCountExternalKeys() method, all which do counting and no modifications.
3f373659d7 Refactor: Replace SigningProvider pointers with unique_ptrs (Andrew Chow)
3afe53c403 Cleanup: Drop unused GUI learnRelatedScripts method (Andrew Chow)
e2f02aa59e Refactor: Copy CWallet signals and print function to LegacyScriptPubKeyMan (Andrew Chow)
c729afd0a3 Box the wallet: Add multiple keyman maps and loops (Andrew Chow)
4977c30d59 refactor: define a UINT256_ONE global constant (Andrew Chow)
415afcccd3 HD Split: Avoid redundant upgrades (Andrew Chow)
01b4511206 Make UpgradeKeyMetadata work only on LegacyScriptPubKeyMan (Andrew Chow)
4a7e43e846 Store p2sh scripts in AddAndGetDestinationForScript (Andrew Chow)
501acb5538 Always try to sign for all pubkeys in multisig (Andrew Chow)
81610eddbc List output types in an array in order to be iterated over (Andrew Chow)
eb81fc3ee5 Refactor: Allow LegacyScriptPubKeyMan to be null (Andrew Chow)
fadc08ad94 Locking: Lock cs_KeyStore instead of cs_wallet in legacy keyman (Andrew Chow)
f5be479694 wallet: Improve CWallet:MarkDestinationsDirty (João Barbosa)
Pull request description:
Continuation of wallet boxes project.
Actually makes ScriptPubKeyMan an interface which LegacyScriptPubkeyMan. Moves around functions and things from CWallet into LegacyScriptPubKeyMan so that they are actually separate things without circular dependencies.
***
Introducing the `ScriptPubKeyMan` (short for ScriptPubKeyManager) for managing scriptPubKeys and their associated scripts and keys. This functionality is moved over from `CWallet`. Instead, `CWallet` will have a pointer to a `ScriptPubKeyMan` for every possible address type, internal and external. It will fetch the correct `ScriptPubKeyMan` as necessary. When fetching new addresses, it chooses the `ScriptPubKeyMan` based on address type and whether it is change. For signing, it takes the script and asks each `ScriptPubKeyMan` for whether that `ScriptPubKeyMan` considers that script `IsMine`, whether it has that script, or whether it is able to produce a signature for it. If so, the `ScriptPubKeyMan` will provide a `SigningProvider` to the caller which will use that in order to sign.
There is currently one `ScriptPubKeyMan` - the `LegacyScriptPubKeyMan`. Each `CWallet` will have only one `LegacyScriptPubKeyMan` with the pointers for all of the address types and change pointing to this `LegacyScriptPubKeyMan`. It is created when the wallet is loaded and all keys and metadata are loaded into it instead of `CWallet`. The `LegacyScriptPubKeyMan` is primarily made up of all of the key and script management that used to be in `CWallet`. For convenience, `CWallet` has a `GetLegacyScriptPubKeyMan` which will return the `LegacyScriptPubKeyMan` or a `nullptr` if it does not have one (not yet implemented, but callers will check for the `nullptr`). For purposes of signing, `LegacyScriptPubKeyMan`'s `GetSigningProvider` will return itself rather than a separate `SigningProvider`. This will be different for future `ScriptPubKeyMan`s.
The `LegacyScriptPubKeyMan` will also handle the importing and exporting of keys and scripts instead of `CWallet`. As such, a number of RPCs have been limited to work only if a `LegacyScriptPubKeyMan` can be retrieved from the wallet. These RPCs are `sethdseed`, `addmultisigaddress`, `importaddress`, `importprivkey`, `importpubkey`, `importmulti`, `dumpprivkey`, and `dumpwallet`. Other RPCs which relied on the wallet for scripts and keys have been modified in order to take the `SigningProvider` retrieved from the `ScriptPubKeyMan` for a given script.
Overall, these changes should not effect how everything actually works and the user should experience no difference between having this change and not having it. As such, no functional tests were changed, and the only unit tests changed were those that were directly accessing `CWallet` functions that have been removed.
This PR is the last step in the [Wallet Structure Changes](https://github.com/bitcoin-core/bitcoin-devwiki/wiki/Wallet-Class-Structure-Changes).
ACKs for top commit:
instagibbs:
re-utACK https://github.com/bitcoin/bitcoin/pull/17261/commits/3f373659d732a5b1e5fdc692a45b2b8179f66bec
Sjors:
re-utACK 3f373659d7 (it still compiles on macOS after https://github.com/bitcoin/bitcoin/pull/17261#discussion_r370377070)
meshcollider:
Tested re-ACK 3f373659d7
Tree-SHA512: f8e2b8d9efa750b617691e8702d217ec4c33569ec2554a060141d9eb9b9a3a5323e4216938e2485c44625d7a6e0925d40dea1362b3af9857cf08860c2f344716
f41d589669 Document better -keypool as a look-ahead safety mechanism (Antoine Riard)
Pull request description:
If after a backup, an address is issued beyond the initial
keypool range and none of the addresses in this range
is seen onchain, if a wallet is restored from backup, even in
case of rescan, funds may be loss due to the look-ahead
buffer not being incremented and so restored wallet not detecting
onchain out-of-range address as derived from its seed.
This scenario is theoretically unavoidable due to the requirement
of the keypool to have a max size. However, given the default
keypool size, this is unlikely. Document better keypool size
implications to avoid user setting a too low value.
While reviewing #17681, it took me a while to figure out the safety implications of keypool, I find it would be better to document this a bit farther to avoid users shooting themselves in the foot. For further context & discussion, see https://github.com/bitcoin/bitcoin/pull/17681#issuecomment-563613452
ACKs for top commit:
ryanofsky:
Code review ACK f41d589669. Just "Warning:" prefix added since the last review
jonatack:
ACK f41d589669 code review and build/test. The added `Warning:` since last review is a good addition.
Tree-SHA512: d3d0ee88fcdfc5c8841a2bd4bada0e4eeb412a0dce5054e5fb023643c2fa57206a0f3efb06890c245528dc4431413ed2fd5645b9319d26245d044c490b7f0db0
Needed for future ScriptPubKeyMans which may need to create
SigningProviders dynamically and thus a normal pointer is not enough
This commit does not change behavior.
Add wallet logic for dealing with multiple ScriptPubKeyMan instances. This
doesn't change current behavior because there is still only a single
LegacyScriptPubKeyMan. But in the future the new logic will be used to support
descriptor wallets.
-BEGIN VERIFY SCRIPT-
# Delete outdated alias for RecursiveMutex
sed -i -e '/CCriticalSection/d' ./src/sync.h
# Replace use of outdated alias with RecursiveMutex
sed -i -e 's/CCriticalSection/RecursiveMutex/g' $(git grep -l CCriticalSection)
-END VERIFY SCRIPT-
If after a backup, an address is issued beyond the initial
keypool range and none of the addresses in this range
is seen onchain, if a wallet is restored from backup, even in
case of rescan, funds may be loss due to the look-ahead
buffer not being incremented and so restored wallet not detecting
onchain out-of-range address as derived from its seed.
This scenario is theoretically unavoidable due to the requirement
of the keypool to have a max size. However, given the default
keypool size, this is unlikely. Document better keypool size
implications to avoid user setting a too low value.
6e77a7b65c keypool: Add comment about TopUp and when to use it (Andrew Chow)
ea50e34b28 keypool: Move opportunistic TopUps from LegacyScriptPubKeyMan to CWallet and ReserveDestination (Andrew Chow)
bb2c8ce23c keypool: Remove superfluous topup from CWallet::GetNewChangeDestination (Andrew Chow)
Pull request description:
* The `TopUp()` in `CWallet::GetNewChangeDestination` is unnecessary as currently m_spk_man calls TopUp further down the call stack inside LegacyScriptPubKeyMan::ReserveKeyFromKeyPool (called by LegacyScriptPubKeyMan::GetReservedDestination). This also lets us prepare for future changes with multiple ScriptPubKeyMans in the wallet.
* An opportunistic `TopUp()` is moved from `LegacyScriptPubKeyMan::GetNewDestination` to `CWallet::GetNewDestination`.
* Another opportunistic `TopUp()` is moved from `LegacyScriptPubKeyMan::ReserveKeyFromKeyPool`
Moving opportunistic TopUps ensures that ScriptPubKeyMans will always be topped up before requesting Destinations from them as we cannot always rely on future ScriptPubKeyMan implementaions topping up internally.
See also: https://github.com/bitcoin/bitcoin/pull/17373#discussion_r348598174
ACKs for top commit:
instagibbs:
utACK https://github.com/bitcoin/bitcoin/pull/17537/commits/6e77a7b65cda1b46ce42f0c99ca91562255aeb28 only change is slight elaboration on comment
ryanofsky:
Code review ACK 6e77a7b65c. Only the comment changed since my previous review.
Tree-SHA512: bdfc8d303842c3fb7c3d40af7abfa6d9dac4ef71a24922bb92229674ee89bfe3113ebb46d3903ac48ef99f0a7d6eaac33282495844f2b31f91b8df55084c421f
Removes SetCrypted() and fUseCrypto as we don't need them anymore.
SetCrypted calls in LegacyScriptPubKeyMan are replaced with mapKeys.empty()
IsCrypted() is changed to just call HasEncryptionKeys()