set up data handler mechanism

Data that comes from outside of the IPMI packet will leverage a data
interface implementation.  Only the IPMI blocktransfer (or really KCS)
will not use this external interface.

Change-Id: I7806da04c070dc3d6a79070ea563aeec63221dca
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/pci_handler.hpp b/pci_handler.hpp
new file mode 100644
index 0000000..df936e4
--- /dev/null
+++ b/pci_handler.hpp
@@ -0,0 +1,20 @@
+#pragma once
+
+#include "data_handler.hpp"
+
+#include <cstdint>
+#include <vector>
+
+namespace blobs
+{
+
+class PciDataHandler : public DataInterface
+{
+
+  public:
+    PciDataHandler() = default;
+
+    std::vector<std::uint8_t> copyFrom(std::uint32_t length) override;
+};
+
+} // namespace blobs