// This file was extracted from the TCG Published
// Trusted Platform Module Library
// Part 4: Supporting Routines
// Family "2.0"
// Level 00 Revision 01.16
// October 30, 2014
#include "stdint.h"
#include "TpmBuildSwitches.h"
const char notReallyUnique[] =
"This is not really a unique value. A real unique value should"
" be generated by the platform.";
//
//
// _plat__GetUnique()
//
// This function is used to access the platform-specific unique value. This function places the unique value
// in the provided buffer (b) and returns the number of bytes transferred. The function will not copy more
// data than bSize.
//
// NOTE: If a platform unique value has unequal distribution of uniqueness and bSize is smaller than the size of the
// unique value, the bSize portion with the most uniqueness should be returned.
//
LIB_EXPORT uint32_t
_plat__GetUnique(
uint32_t which, // authorities (0) or details
uint32_t bSize, // size of the buffer
unsigned char *b // output buffer
)
{
const char *from = notReallyUnique;
uint32_t retVal = 0;
if(which == 0) // the authorities value
{
for(retVal = 0;
*from != 0 && retVal < bSize;
retVal++)
{
*b++ = *from++;
}
}
else
{
#define uSize sizeof(notReallyUnique)
b = &b[((bSize < uSize) ? bSize : uSize) - 1];
for(retVal = 0;
*from != 0 && retVal < bSize;
retVal++)
{
*b-- = *from++;
}
}
return retVal;
}