
Freescale Semiconductor
34-1
Chapter 34
Random Number Generator (RNG)
34.1
Introduction
This chapter describes the random number generator (RNG), including a programming model, functional
description, and application information.
NOTE
The MCF5327, MCF53281, and MCF5328 do not contain cryptography
modules. Refer to
for details on device configurations.
34.1.1
Overview
The random number generator (RNG) module is capable of generating 32-bit random numbers. It complies
with Federal Information Processing Standard (FIPS) 140 standards for randomness and non-determinism.
The random bits generate by clocking shift registers with clocks derived from ring oscillators. The
configuration of the shift registers ensures statistically good data (data that looks random). The oscillators
with their unknown frequencies provide the required entropy needed to create random data.
CAUTION
There is no known cryptographic proof showing that this is a secure method
of generating random data. In fact, there may be an attack against the
random number generator if its output is used directly in a cryptographic
application (the attack is based on the linearity of the internal shift registers).
In light of this, it is highly
recommended to use the random data produced
by this module as an input seed to a NIST-approved (based on DES or
SHA-1) or cryptographically-secure (RSA generator or BBS generator)
random number generation algorithm.
It is also recommended to use other sources of entropy along with the RNG
to generate the seed to the pseudorandom algorithm. The more random
sources combined to create the seed the better. The following is a list of
sources that can be easily combined with the output of this module.
– Current time using highest precision possible
– Mouse and keyboard motions (or equivalent if being used on a cell phone or PDA)
– Other entropy supplied directly by the user
MCF5329 Reference Manual, Rev 3
Summary of Contents for MCF5329
Page 106: ...ColdFire Core 3 32 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 148: ...Cache 5 22 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 154: ...Static RAM SRAM 6 6 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 184: ...Power Management 8 18 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 204: ...Reset Controller Module 10 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 220: ...System Control Module SCM 11 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 228: ...Crossbar Switch XBS 12 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 268: ...General Purpose I O Module 13 40 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 392: ...SDRAM Controller SDRAMC 18 30 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 436: ...Fast Ethernet Controller FEC 19 44 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 594: ...FlexCAN 23 30 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 678: ...Pulse Width Modulation PWM Module 26 22 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 684: ...Watchdog Timer Module 27 6 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 704: ...DMA Timers DTIM0 DTIM3 29 12 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 754: ...UART Modules 31 34 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 770: ...I2 C Interface 32 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 866: ...Debug Module 36 50 Freescale Semiconductor MCF5329 Reference Manual Rev 3...