1 files changed, 24 insertions, 7 deletions

diff --git a/src/hash.h b/src/hash.h
index 71806483ff..c16bbb48ce 100644
--- a/src/hash.h
+++ b/src/hash.h
@@ -6,6 +6,7 @@
 #ifndef BITCOIN_HASH_H
 #define BITCOIN_HASH_H
 
+#include <attributes.h>
 #include <crypto/common.h>
 #include <crypto/ripemd160.h>
 #include <crypto/sha256.h>
@@ -98,7 +99,7 @@ inline uint160 Hash160(const T1& in1)
 class CHashWriter
 {
 private:
-    CHash256 ctx;
+    CSHA256 ctx;
 
     const int nType;
     const int nVersion;
@@ -110,13 +111,27 @@ public:
     int GetVersion() const { return nVersion; }
 
     void write(const char *pch, size_t size) {
-        ctx.Write({(const unsigned char*)pch, size});
+        ctx.Write((const unsigned char*)pch, size);
     }
 
-    // invalidates the object
+    /** Compute the double-SHA256 hash of all data written to this object.
+     *
+     * Invalidates this object.
+     */
     uint256 GetHash() {
         uint256 result;
-        ctx.Finalize(result);
+        ctx.Finalize(result.begin());
+        ctx.Reset().Write(result.begin(), CSHA256::OUTPUT_SIZE).Finalize(result.begin());
+        return result;
+    }
+
+    /** Compute the SHA256 hash of all data written to this object.
+     *
+     * Invalidates this object.
+     */
+    uint256 GetSHA256() {
+        uint256 result;
+        ctx.Finalize(result.begin());
         return result;
     }
 
@@ -124,9 +139,8 @@ public:
      * Returns the first 64 bits from the resulting hash.
      */
     inline uint64_t GetCheapHash() {
-        unsigned char result[CHash256::OUTPUT_SIZE];
-        ctx.Finalize(result);
-        return ReadLE64(result);
+        uint256 result = GetHash();
+        return ReadLE64(result.begin());
     }
 
     template<typename T>
@@ -181,6 +195,9 @@ uint256 SerializeHash(const T& obj, int nType=SER_GETHASH, int nVersion=PROTOCOL
     return ss.GetHash();
 }
 
+/** Single-SHA256 a 32-byte input (represented as uint256). */
+NODISCARD uint256 SHA256Uint256(const uint256& input);
+
 unsigned int MurmurHash3(unsigned int nHashSeed, Span<const unsigned char> vDataToHash);
 
 void BIP32Hash(const ChainCode &chainCode, unsigned int nChild, unsigned char header, const unsigned char data[32], unsigned char output[64]);