This should make it easier for the fuzz engine to explore multisig code
paths. See discussion in https://github.com/bitcoin/bitcoin/issues/23105
The downside is that all fuzz inputs that use ConsumeScript are now
invalidated and need to be re-generated.
Another downside may be that most multisig scripts from ConsumeScript are
using likely not fully valid pubkeys.
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.
In preparation for adding Schnorr versions of `CheckSig`, `VerifySignature`, and
`ComputeEntry`, give them an ECDSA specific name.
-BEGIN VERIFY SCRIPT-
sed -i 's/CheckSig(/CheckECDSASignature(/g' $(git grep -l CheckSig ./src)
sed -i 's/VerifySignature(/VerifyECDSASignature(/g' $(git grep -l VerifySignature ./src)
sed -i 's/ComputeEntry(/ComputeEntryECDSA(/g' $(git grep -l ComputeEntry ./src)
-END VERIFY SCRIPT-
and also
- add missing parentheses in fuzz/scriptnum_ops.cpp
- remove useless unsigned int conditional in fuzz/script.cpp
These changes fix 5 compile warnings in gcc 10.
