Support for Schnorr signatures and integration in SignatureCheckers (BIP 340)

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.

1 files changed, 2 insertions, 0 deletions

diff --git a/src/script/sigcache.h b/src/script/sigcache.h
index 49c6b192e9..00534f9758 100644
--- a/src/script/sigcache.h
+++ b/src/script/sigcache.h
@@ -7,6 +7,7 @@
 #define BITCOIN_SCRIPT_SIGCACHE_H
 
 #include <script/interpreter.h>
+#include <span.h>
 
 #include <vector>
 
@@ -49,6 +50,7 @@ public:
     CachingTransactionSignatureChecker(const CTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn, bool storeIn, PrecomputedTransactionData& txdataIn) : TransactionSignatureChecker(txToIn, nInIn, amountIn, txdataIn), store(storeIn) {}
 
     bool VerifyECDSASignature(const std::vector<unsigned char>& vchSig, const CPubKey& vchPubKey, const uint256& sighash) const override;
+    bool VerifySchnorrSignature(Span<const unsigned char> sig, const XOnlyPubKey& pubkey, const uint256& sighash) const override;
 };
 
 void InitSignatureCache();