diff --git a/flash-ipmi.cpp b/flash-ipmi.cpp
index 42333dd..f58363b 100644
--- a/flash-ipmi.cpp
+++ b/flash-ipmi.cpp
@@ -47,6 +47,7 @@
 void FlashUpdate::closeEverything()
 {
     closeFile(&flashFd);
+    closeFile(&hashFd);
 }
 
 FlashUpdate::~FlashUpdate()
@@ -76,6 +77,19 @@
         return false;
     }
 
+    /* hash path is basically optional. */
+    if (!hashPath.empty())
+    {
+        hashFd = std::fopen(hashPath.c_str(), "wb");
+        if (hashFd == nullptr)
+        {
+            log<level::INFO>("Unable to open hash storage path",
+                             entry("PATH=%s", hashPath.c_str()));
+            closeFile(&flashFd);
+            return false;
+        }
+    }
+
     return true;
 }
 
@@ -141,8 +155,13 @@
 
 bool FlashUpdate::startHash(uint32_t length)
 {
-    /* TODO: implement. */
-    return false;
+    if (!hashFd)
+    {
+        return false;
+    }
+
+    hashLength = length;
+    return true;
 }
 
 bool FlashUpdate::hashData(uint32_t offset, const std::vector<uint8_t>& bytes)