1 files changed, 17 insertions, 0 deletions
diff --git a/src/hash.cpp b/src/hash.cpp
index 4c09f5f646..3657b38639 100644
--- a/src/hash.cpp
+++ b/src/hash.cpp
@@ -6,6 +6,7 @@
 #include <crypto/common.h>
 #include <crypto/hmac_sha512.h>
 
+#include <string>
 
 inline uint32_t ROTL32(uint32_t x, int8_t r)
 {
@@ -77,3 +78,19 @@ void BIP32Hash(const ChainCode &chainCode, unsigned int nChild, unsigned char he
     num[3] = (nChild >>  0) & 0xFF;
     CHMAC_SHA512(chainCode.begin(), chainCode.size()).Write(&header, 1).Write(data, 32).Write(num, 4).Finalize(output);
 }
+
+uint256 SHA256Uint256(const uint256& input)
+{
+    uint256 result;
+    CSHA256().Write(input.begin(), 32).Finalize(result.begin());
+    return result;
+}
+
+CHashWriter TaggedHash(const std::string& tag)
+{
+    CHashWriter writer(SER_GETHASH, 0);
+    uint256 taghash;
+    CSHA256().Write((const unsigned char*)tag.data(), tag.size()).Finalize(taghash.begin());
+    writer << taghash << taghash;
+    return writer;
+}