RECENT BLOG NEWS

With #ARMTechCon this week, we wanted to let the ARM community know about wolfSSL, the best tested crypto and SSL/TLS stack available for embedded devices and the IoT!

The security of wolfSSL products is always on our mind and holds high importance.  Conducting regular, diligent, and well-planned testing helps maintain wolfSSL’s robustness and security.  We strive to write and maintain clean, readable, and understandable code.

Like the halting problem, we know it is impossible to test every single possible path through the software, but we practice an approach that is focused on lowering risk of failure. In addition to extensive automated testing, we make sure that we specifically test well-known use cases. This post outlines some of our internal testing process.

1) API Unit Testing:  We have unit tests in place that test API functions for correct behavior. This helps maintain library consistency across releases and as the code evolves.  It helps us to deliver a high quality well tested API to our end users with each software release.  API unit tests are run with each “make check” of wolfSSL.

2) Cipher Suite Testing: wolfSSL supports an extensive list of cipher suites, which are all tested with every “make check” using the wolfSSL example client and example server.  Each cipher suite is tested not only in the default configuration, but also in non-blocking mode and with client authentication both turned on/off.

3) Algorithm Testing: The security of our SSL/TLS implementation depends on the correctness and robustness of our underlying cryptography library, wolfCrypt.  We test all algorithms using NIST test vectors in addition to running our CAVP test harness used for our FIPS 140-2 validations.  We also test on both big and little endian platforms for portability.

4) Benchmark Testing: We engage in another ever expanding universe of benchmark testing, where we look at sizing, transmission rates, connection speeds, and cryptography performance.  A version of our benchmark suite is included in every download for users to enjoy!

5) Static Analysis: We do static analysis on our entire codebase using not only one, but multiple different static analysis tools.  We currently use Coverity Scan, clang scan-build, and Facebook infer.  These tools help us to automatically find bugs including ones on low-traffic code paths.

6) Detecting Memory Errors:  We mitigate memory errors by using valgrind on a regular and automated basis.  This helps find memory errors including invalid access, use of undefined values, incorrect freeing of dynamic memory, and memory leaks.

7) Interop Testing: We test for interoperability with other Open Source TLS implementations, including OpenSSL, BoringSSL, and GnuTLS.  This helps us to catch any protocol implementation errors in either wolfSSL or the implementation being tested against.  We also test outside of a closed environment by connecting to servers in the real world running unknown SSL/TLS implementations.

8) Real World Builds: We build with a series of `real` applications, like cURL, wget, pppd, OpenSSH, stunnel, lighttpd, etc.  For some of our customers with top level support, we build new releases with their application.

9) Compiler Testing: We have users who compile wolfSSL with a variety of different compilers.  As such, we test compiling wolfSSL with many different compilers and toolchains including gcc/g++, clang, icc, Visual Studio, CodeWarrior, KDS, LPCXpresso, MPLAB XC, TI CCS, Keil, IAR, Cygwin, MinGW, CrossWorks, Arduino, Wind River Workbench, and more.

10) Peer Review: More eyes on a codebase reduces bugs that end up in a final product.  Internally, we operate using a “Fork and Pull Request” model.  This means that every commit that makes it into our master branch has been reviewed and tested by at least two separate engineers.

11) Third Party Testing: Our code is regularly reviewed by university researchers, customer and user security teams, FIPS and certification labs, and our Open Source user base.  This helps put more eyes on our code and product architecture.

12) Fuzz Testing: We test using several different software fuzzers, including an in-memory fuzzer and a network fuzzer.  This bombards the program with invalid, unexpected, and random data that then allows for observing if there is potential memory leaks or logic errors.  This allows us to catch bugs that could turn into potential vulnerabilities if released in a final release.

13) Continuous Integration (CI): Leveraging Jenkins, we run tests on each commit submitted to the wolfSSL code repository.  Tests run on each commit include testing of our FIPS build, numerous build options (customer/user/common), running valgrind, and doing static analysis with scan-build.

14) Nightly Test Cycle: Each night we run extended tests that last longer than the typical ones during the work day.  These are more in-depth than our CI testing and puts results in our engineers’ inboxes each morning.  Some tests included in our nightly cycle include extended build option testing on multiple platforms with multiple compilers, and extended fuzz testing.

If you have specific questions about how we test, please contact us at facts@wolfssl.com.  If you would like us to include your SSL/TLS or crypto implementation in our interop testing, please let us know!  Likewise, if you would like to include wolfSSL in your own test framework, we would be happy to discuss.

With #ArmTechCon under way, we wanted to remind our users that the @wolfSSL embedded SSL library is integrated into Keil MDK5 as an easy-to-use software pack. In addition to the library itself, several out-of-the-box example projects using wolfSSL are also available. wolfSSL also supports Keil RTX!

To discuss this more at #ArmTechCon stop by booth #321 and visit with the best ARM security team out there, @wolfSSL!

Documentation for wolfSSL with Keil MDK-ARM can be found here: https://www.wolfssl.com/docs/keil-mdk-arm/

#ARMTechCon – Did you know that the wolfSSL embedded SSL library supports FreeRTOS and OpenRTOS, and have also done several FIPS 140-2 validations on both?  FreeRTOS is a real-time operating system for embedded devices which is designed to be both small and simple.

Just like wolfSSL, FreeRTOS is open source, royalty free, and very portable.  To build wolfSSL for FreeRTOS, uncomment the #define for FREERTOS in ./wolfssl/wolfcrypt/settings.h, or add it to your own custom <user_settings.h> header file.

You can find a full list of FreeRTOS features on the FreeRTOS/OpenRTOS website.  To learn more about wolfSSL, please visit the wolfSSL product page.  If you have any questions about using wolfSSL with FreeRTOS, please contact us at facts@wolfssl.com.

#ARMTechCon – Do you have an ARM-based Raspberry Pi project and are looking for a lightweight SSL library with a low overhead to save memory for your project? Are you looking for something open source? Look no further than wolfSSL, formerly CyaSSL. You can obtain the source from our wolfSSL GitHub repository. It builds easily using standard tools included on the Pi. You can even obtain Python wrappers via pip. Thank you and happy hacking!

#ARMTechCon – Do you have a need for an SSH server for your ARM based IoT environment? wolfSSH can satisfy that need in any environment that can run wolfSSL. With a light footprint, wolfSSH can give any lightweight platform an SSH server. It can be used to provide a network interface to devices that used to have serial ports. Or could be used to transfer files into and out of an embedded device. Please send us an email if you are interested in wolfSSH for ARM devices!

The wolfSSH library is dual-license open-source GPLv3 and commercial.

#ARMTechCon – @wolfSSL has partnered with @GreenHillsPR who has ported the wolfSSL #embedded TLS library into Integrity RTOS! @GreenHillsPR and @wolfSSL will be exhibiting at #ARMTechCon in Santa Clara, CA. Stop by booth #321 to visit with the wolfSSL Team and discuss any questions!

Reference: https://twitter.com/greenhillspr

On the topic of #ARMTechCon, wolfSSL is available as a CMSIS pack! wolfSSL was one of the first libraries available as a MDK5 software pack, which has evolved into CMSIS.

The wolfSSL ARM MDK5 pack supports CMSIS-RTOS by default, providing both the library and example applications. The user can choose to use a different OS as well. Contact us at support@wolfssl.com for more information about using the wolfSSL CMSIS pack today.

Just in time for the #ARMTechCon 2016, wolfSSL is making hardware accelerated crypto easier than ever on STM32 devices. This is being done by integrating wolfCrypt into STM`s Hardware Abstraction Layer (HAL) through CubeMX. wolfSSL support for CubeMX with HAL will remove the need to tediously configure hardware acceleration by hand and instead let STM32CubeMX, a graphical software from STM, handle the setup of these features.

wolfSSL is currently testing compatibility on STM32F439ZIx and a STM32F437IIHx boards, but with more support coming soon. If you are interested in getting early access to these features and seeing how easily you can benefit from hardware acceleration, contact support@wolfssl.com.

#ARMTechCon – wolfSSL now supports Xilinx SoCs and FPGAs. The wolfSSL embedded SSL/TLS library can be used with FPGAs which use the MicroBlaze CPU and/or Zynq and Zynq UltraScale+ SoCs.
 
For more information contact facts@wolfssl.com

#ARMTechCon – NXP has a new LP Trusted Crypto (LTC) core which accelerates RSA/ECC PKI in their Kinetis K8x line.

The LTC hardware accelerator improves:
 * RSA performance by 12-17X
 * ECC performance by 18-23X
 * Ed/Curve25519 performance by 2-3X.

This adds to the existing MMCAU support which accelerates RNG, AES (CBC, CCM, GCM, CTR), DES/3DES, MD5, SHA, SHA256, SHA384/512 and ChaCha20/Poly1305.

The combined LTC/MMCAU hardware acceleration improves performance, reduces power consumption and reduces code size by 40%.

Here are the benchmarks on a FRDM-K82F Cortex M4 @ 150MHz:

Hardware Accelerated (LTC / MMCAU):
RNG      25 kB took 0.026 seconds,    0.939 MB/s
AES enc  25 kB took 0.002 seconds,   12.207 MB/s
AES dec  25 kB took 0.002 seconds,   12.207 MB/s
AES-GCM  25 kB took 0.002 seconds,   12.207 MB/s
AES-CTR  25 kB took 0.003 seconds,    8.138 MB/s
AES-CCM  25 kB took 0.004 seconds,    6.104 MB/s
CHACHA   25 kB took 0.008 seconds,    3.052 MB/s
CHA-POLY 25 kB took 0.013 seconds,    1.878 MB/s
POLY1305 25 kB took 0.003 seconds,    8.138 MB/s
SHA      25 kB took 0.006 seconds,    4.069 MB/s
SHA-256  25 kB took 0.009 seconds,    2.713 MB/s
SHA-384  25 kB took 0.032 seconds,    0.763 MB/s
SHA-512  25 kB took 0.035 seconds,    0.698 MB/s
RSA 2048 public          12.000 milliseconds, avg over 1 iterations
RSA 2048 private         135.000 milliseconds, avg over 1 iterations
ECC  256 key generation  17.400 milliseconds, avg over 5 iterations
EC-DHE   key agreement   15.200 milliseconds, avg over 5 iterations
EC-DSA   sign   time     20.200 milliseconds, avg over 5 iterations
EC-DSA   verify time     33.000 milliseconds, avg over 5 iterations
CURVE25519 256 key generation 14.400 milliseconds, avg over 5 iterations
CURVE25519 key agreement      14.400 milliseconds, avg over 5 iterations
ED25519  key generation  14.800 milliseconds, avg over 5 iterations
ED25519  sign   time     16.800 milliseconds, avg over 5 iterations
ED25519  verify time     30.400 milliseconds, avg over 5 iterations

Software only:
RNG      25 kB took 0.179 seconds,    0.136 MB/s
AES enc  25 kB took 0.099 seconds,    0.247 MB/s
AES dec  25 kB took 0.102 seconds,    0.239 MB/s
AES-GCM  25 kB took 1.486 seconds,    0.016 MB/s
AES-CTR  25 kB took 0.099 seconds,    0.247 MB/s
AES-CCM  25 kB took 0.201 seconds,    0.121 MB/s
CHACHA   25 kB took 0.043 seconds,    0.568 MB/s
CHA-POLY 25 kB took 0.055 seconds,    0.444 MB/s
POLY1305 25 kB took 0.010 seconds,    2.441 MB/s
SHA      25 kB took 0.029 seconds,    0.842 MB/s
SHA-256  25 kB took 0.079 seconds,    0.309 MB/s
SHA-384  25 kB took 0.109 seconds,    0.224 MB/s
SHA-512  25 kB took 0.113 seconds,    0.216 MB/s
RSA 2048 public          147.000 milliseconds, avg over 1 iterations
RSA 2048 private         2363.000 milliseconds, avg over 1 iterations
ECC  256 key generation  355.400 milliseconds, avg over 5 iterations
EC-DHE   key agreement   352.400 milliseconds, avg over 5 iterations
EC-DSA   sign   time     362.400 milliseconds, avg over 5 iterations
EC-DSA   verify time     703.400 milliseconds, avg over 5 iterations
CURVE25519 256 key generation 66.200 milliseconds, avg over 5 iterations
CURVE25519 key agreement      65.400 milliseconds, avg over 5 iterations
ED25519  key generation  25.000 milliseconds, avg over 5 iterations
ED25519  sign   time     30.400 milliseconds, avg over 5 iterations
ED25519  verify time     74.400 milliseconds, avg over 5 iterations

The code to support the LTC is currently in PR #597 here, soon to be rolled into the wolfSSL embedded SSL/TLS library:
https://github.com/wolfSSL/wolfssl/pull/597

These changes are also included in the KSDK 2.0.

See us at ARM TechCon booth #321 (Wednesday 10/26 and Thursday 10/27 – 10:30 AM – 6:30 PM)