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NIST SP800-22b test suite running and analyzing

Note:

The USART configuration can be changed by the user via the SendToWorkstation() function

in the main.c file.

The output values can be changed by the user by modifying the Private define in the main.c

file:

#define NUMBER_OF_RANDOM_BITS_TO_GENERATE 512000

#define BLOCK_NUMBER 10

3.1.2

On the NIST SP800-22b test suite side

Downloaded on a workstation, the NIST statistical test suite package sts-2.1.1 verifies the

randomness of the output file of the random number generator from STM32 F2/F4 products.

The generator file to be analyzed should be stored under the data folder (sts-2.1.1\data).

For more details about how the NIST statistical tests work, refer to section How to Get

Started in “A Statistical Test Suite for Random and Pseudorandom Number Generators for

Cryptographic Applications” Special Publication 800-22 Revision 1a.

3.2

NIST SP800-22b test suite steps

Figure 2 describes the different steps needed to verify the randomness of an output number

generated by STM32 F2/F4 using the NIST statistical test suite package sts-2.1.1.

Figure 2. Block diagram of deviation testing of a binary sequence from randomness

based on NIST test suite

3.2.1

First step: random number generator

Connect STMicroelectronics evaluation board (STM322xG-EVAL” for STM32F2 series or

STM324xG-EVAL” for STM32F4 series) with DB9 connector CN16 (USART3) to the

workstation serial port via a null-modem female/female RS232 cable. Then, run STM32

RNG generation via the UART firmware using your preferred toolchain in order to generate

a random number as described in the previous section. You can store data on the