1 files changed, 45 insertions, 6 deletions

diff --git a/src/script/sigcache.h b/src/script/sigcache.h
index d33d60d5bc..76802e6a7c 100644
--- a/src/script/sigcache.h
+++ b/src/script/sigcache.h
@@ -6,32 +6,71 @@
 #ifndef BITCOIN_SCRIPT_SIGCACHE_H
 #define BITCOIN_SCRIPT_SIGCACHE_H
 
+#include <consensus/amount.h>
+#include <crypto/sha256.h>
+#include <cuckoocache.h>
 #include <script/interpreter.h>
 #include <span.h>
+#include <uint256.h>
 #include <util/hasher.h>
 
-#include <optional>
+#include <cstddef>
+#include <shared_mutex>
 #include <vector>
 
+class CPubKey;
+class CTransaction;
+class XOnlyPubKey;
+
 // DoS prevention: limit cache size to 32MiB (over 1000000 entries on 64-bit
 // systems). Due to how we count cache size, actual memory usage is slightly
 // more (~32.25 MiB)
-static constexpr size_t DEFAULT_MAX_SIG_CACHE_BYTES{32 << 20};
+static constexpr size_t DEFAULT_VALIDATION_CACHE_BYTES{32 << 20};
+static constexpr size_t DEFAULT_SIGNATURE_CACHE_BYTES{DEFAULT_VALIDATION_CACHE_BYTES / 2};
+static constexpr size_t DEFAULT_SCRIPT_EXECUTION_CACHE_BYTES{DEFAULT_VALIDATION_CACHE_BYTES / 2};
+static_assert(DEFAULT_VALIDATION_CACHE_BYTES == DEFAULT_SIGNATURE_CACHE_BYTES + DEFAULT_SCRIPT_EXECUTION_CACHE_BYTES);
 
-class CPubKey;
+/**
+ * Valid signature cache, to avoid doing expensive ECDSA signature checking
+ * twice for every transaction (once when accepted into memory pool, and
+ * again when accepted into the block chain)
+ */
+class SignatureCache
+{
+private:
+    //! Entries are SHA256(nonce || 'E' or 'S' || 31 zero bytes || signature hash || public key || signature):
+    CSHA256 m_salted_hasher_ecdsa;
+    CSHA256 m_salted_hasher_schnorr;
+    typedef CuckooCache::cache<uint256, SignatureCacheHasher> map_type;
+    map_type setValid;
+    std::shared_mutex cs_sigcache;
+
+public:
+    SignatureCache(size_t max_size_bytes);
+
+    SignatureCache(const SignatureCache&) = delete;
+    SignatureCache& operator=(const SignatureCache&) = delete;
+
+    void ComputeEntryECDSA(uint256& entry, const uint256 &hash, const std::vector<unsigned char>& vchSig, const CPubKey& pubkey) const;
+
+    void ComputeEntrySchnorr(uint256& entry, const uint256 &hash, Span<const unsigned char> sig, const XOnlyPubKey& pubkey) const;
+
+    bool Get(const uint256& entry, const bool erase);
+
+    void Set(const uint256& entry);
+};
 
 class CachingTransactionSignatureChecker : public TransactionSignatureChecker
 {
 private:
     bool store;
+    SignatureCache& m_signature_cache;
 
 public:
-    CachingTransactionSignatureChecker(const CTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn, bool storeIn, PrecomputedTransactionData& txdataIn) : TransactionSignatureChecker(txToIn, nInIn, amountIn, txdataIn, MissingDataBehavior::ASSERT_FAIL), store(storeIn) {}
+    CachingTransactionSignatureChecker(const CTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn, bool storeIn, SignatureCache& signature_cache, PrecomputedTransactionData& txdataIn) : TransactionSignatureChecker(txToIn, nInIn, amountIn, txdataIn, MissingDataBehavior::ASSERT_FAIL), store(storeIn), m_signature_cache(signature_cache)  {}
 
     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;
 };
 
-[[nodiscard]] bool InitSignatureCache(size_t max_size_bytes);
-
 #endif // BITCOIN_SCRIPT_SIGCACHE_H