This adds a new `SigVersion::TAPSCRIPT`, makes the necessary interpreter
changes to make it implement BIP342, and uses them for leaf version 0xc0
in Taproot script path spends.
This includes key path spending and script path spending, but not the
Tapscript execution implementation (leaf 0xc0 remains unemcumbered in
this commit).
Includes constants for various aspects of the consensus rules suggested
by Jeremy Rubin.
This enables the schnorrsig module in libsecp256k1, adds the relevant types
and functions to src/pubkey, as well as in higher-level `SignatureChecker`
classes. The (verification side of the) BIP340 test vectors is also added.
Error messages in cleanstack is misleading as
it lets the user believe that there are extra
elements on stack which is incorrect if the
stack is empty.
This disables OP_CODESEPARATOR in non-segwit scripts (even in an unexecuted branch), and makes a positive FindAndDelete result invalid. This ensures that the scriptCode serialized in SignatureHash() is always the same as the script passing to the EvalScript.
<nLockTime> CHECKLOCKTIMEVERIFY -> <nLockTime>
Fails if tx.nLockTime < nLockTime, allowing the funds in a txout to be
locked until some block height or block time in the future is reached.
Only the logic and unittests are implemented; this commit does not have
any actual soft-fork logic in it.
Thanks to Pieter Wuille for rebase.
Credit goes to Gregory Maxwell for the suggestion of comparing the
argument against the transaction nLockTime rather than the current
time/blockheight directly.
This turns STRICTENC turn into a softforking-safe change (even though it
is not intended as a consensus rule), and as a result guarantee that using
it for mempool validation only results in consensus-valid transactions in
the mempool.
NOP1 to NOP10 are reserved for future soft-fork upgrades. In the event
of an upgrade such NOPs have *VERIFY behavior, meaning that if their
arguments are not correct the script fails. Discouraging these NOPs by
rejecting transactions containing them from the mempool ensures that
we'll never accept transactions, nor mine blocks, with scripts that are
now invalid according to the majority of hashing power even if we're not
yet upgraded. Previously this wasn't an issue as the IsStandard() rules
didn't allow upgradable NOPs anyway, but 7f3b4e95 relaxed the
IsStandard() rules for P2SH redemptions allowing any redeemScript to be
spent.
We *do* allow upgradable NOPs in scripts so long as they are not
executed. This is harmless as there is no opportunity for the script to
be invalid post-upgrade.
Attempt to codify the possible error statuses associated with script
validation. script/types.h has been created with the expectation that it will
be part of the public lib interface. The other flag enums will be moved here in
a future commit.
Logging has also been removed in order to drop the dependency on core.h. It can
be re-added to bitcoind as-needed. This makes script verification finally free
of application state and boost!
