Using MpuPacker to Minimize Waste

The Cortex-M v7 MPU requires regions to be a power of two in size and aligned to their size. This can waste a lot of memory if they aren’t ordered efficiently. We developed our MpuPacker utility to help with this by optimizing the ordering and also recommending regions that can be reduced in size or …

MPU Debugging with smxAware

smxAware was enhanced with new features to help debug issues related to the Memory Protection Unit in SecureSMX systems. These are covered here. The IAR debugger displays the MPU registers like this: RNR can be manually patched to the slot number to view, which then shows the RBAR and RASR values for that slot. A …

MPU Extension

In any real project using a secure RTOS with a Memory Protection Unit (MPU), you are likely to run out of MPU slots for at least some tasks. One group of culprits is peripheral drivers, which tend to require multiple IO regions. If you have only one region to give to your task, you may …

Moving Uptown to Umode

pmode[1] partitions may be just as effective as umode[2] partitions for reliability; however, umode partitions are much better for security for the following reasons: The hardware enforced pmode barrier prevents umode access to pmode data and code.The MPU cannot be turned off nor altered from umode.The Background Region (BR) is ineffective in umode. These combine …

FreeRTOS Security? Not To Worry

It is now possible to greatly increase the security of FreeRTOS projects by porting them to SecureSMX®, using FRPort™. SecureSMX facilitates partitioning an application into isolated partitions. This provides strong protection against hacking since a hacker can only access code and data within the partition that he has entered. In this solution paper, we discuss …

What’s In Your SOUP?

SOUP (Software of Unknown Pedigree) is often incorporated into embedded system projects due to schedule pressure, lack of in-house expertise, or for other reasons, and it ends up in the final product. Such third-party software may be carefully designed, documented, and commented, but it remains a mystery to your team because no one has time …

Where’s The Gold?

Many Things are embedded systems to which networking has recently been added. As such, hackers coming in via the Hacker’s Highway (aka the Internet) can overcome the weak defenses of such systems and gain access to critical information such as encryption keys. As a consequence, entire networks can become compromised all the way into the …

Is Your Thing In Danger?

Introduction The figure below shows the security structure of typical microcontroller embedded software. There is no structure! A hacker who has gained access to the system, has access to anything he wants, including keys and other secrets. This undermines the security afforded by encryption, authentication, and other security methods employed in modern systems. This figure …