1 files changed, 17 insertions, 0 deletions
diff --git a/src/hash.cpp b/src/hash.cpp
index 218607a6fd..2cca06ae23 100644
--- a/src/hash.cpp
+++ b/src/hash.cpp
@@ -1,3 +1,7 @@
+// Copyright (c) 2013-2014 The Bitcoin developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
 #include "hash.h"
 
 inline uint32_t ROTL32(uint32_t x, int8_t r)
@@ -63,3 +67,16 @@ unsigned int MurmurHash3(unsigned int nHashSeed, const std::vector<unsigned char
 
     return h1;
 }
+
+void BIP32Hash(const unsigned char chainCode[32], unsigned int nChild, unsigned char header, const unsigned char data[32], unsigned char output[64])
+{
+    unsigned char num[4];
+    num[0] = (nChild >> 24) & 0xFF;
+    num[1] = (nChild >> 16) & 0xFF;
+    num[2] = (nChild >>  8) & 0xFF;
+    num[3] = (nChild >>  0) & 0xFF;
+    CHMAC_SHA512(chainCode, 32).Write(&header, 1)
+                               .Write(data, 32)
+                               .Write(num, 4)
+                               .Finalize(output);
+}