Initial release

tpm_module/libhis_getrandombytes.hpp

@@ -0,0 +1,71 @@
+#ifndef libhis_getrandombytes_hpp
+#define libhis_getrandombytes_hpp
+
+#ifdef WINDOWS
+	#include "tspi.h"
+	#include "tss_error.h"
+	#include "tss_defines.h"
+#endif
+#ifdef LINUX
+	#include <tss/tspi.h>
+	#include <tss/tss_error.h>
+	#include <tss/tss_defines.h>
+#endif
+
+#include "libhis_exception.hpp"
+
+class libhis_getrandombytes
+{
+public:
+	libhis_getrandombytes()
+	{
+		//create a context object
+		result = Tspi_Context_Create(&hcontext);
+		if(result != TSS_SUCCESS) throw libhis_exception("Create Conntext", result);
+	}
+
+	void getrandombytes(
+		unsigned long bytes_size,
+		unsigned char *&output_value)
+	{
+		//establish a session
+		result = Tspi_Context_Connect(hcontext, 0);
+		if(result != TSS_SUCCESS) throw libhis_exception("Connect Context", result);
+
+		//get the TPM object
+		result = Tspi_Context_GetTpmObject(hcontext, &htpm);
+		if(result != TSS_SUCCESS) throw libhis_exception("Get TPM Object", result);
+
+		//get random bytes
+		BYTE *bytes_value;
+		result = Tspi_TPM_GetRandom(htpm, bytes_size, &bytes_value);
+		if(result != TSS_SUCCESS) throw libhis_exception("Get Random Bytes", result);
+
+		//copy C-style output into C++ format
+		output_value = new unsigned char[bytes_size];
+		for(unsigned long i = 0; i < bytes_size; i++)
+		{
+			output_value[i] = bytes_value[i];
+		}
+
+		//clean up random bytes
+		result = Tspi_Context_FreeMemory(hcontext, bytes_value);
+		if(result != TSS_SUCCESS) throw libhis_exception("Cleanup bytes", result);
+
+		return;
+	}
+
+	~libhis_getrandombytes()
+	{
+		//close context
+		result = Tspi_Context_Close(hcontext);
+		if(result != TSS_SUCCESS) throw libhis_exception("Close Context", result);
+	}
+
+private:
+	TSS_RESULT		result;
+	TSS_HCONTEXT	hcontext;
+	TSS_HTPM		htpm;
+};
+
+#endif