We would like to announce that the wolfSSL embedded SSL library now has support for hardware-based cryptography and random number generation offered by the STM32F2. Supported cryptographic algorithms include AES (CBC, CTR), DES (ECB, CBC), 3DES, MD5, and SHA1. For details regarding the STM32F2 crypto and hash processors, please see the STM32F2xx Standard Peripheral Library document (linked below).
If you are using the STM32F2 with wolfSSL, you can see substantial speed improvements when using the hardware crypto versus using wolfSSL’s software crypto implementation. The following benchmarks were gathered from the CTaoCrypt benchmark application (ctaocrypt/benchmark/benchmark.c) running on the STM3221G-EVAL board (STM32F2) using the STM32F2 Standard Peripheral Library and FreeRTOS.
wolfSSL Software Crypto, Normal Big Integer Math Library
AES 1024 kB took 0.822 seconds, 1.22 MB/s
ARC4 1024 KB took 0.219 seconds, 4.57 MB/s
DES 1024 KB took 1.513 seconds, 0.66 MB/s
3DES 1024 KB took 3.986 seconds, 0.25 MB/s
MD5 1024 KB took 0.119 seconds, 8.40 MB/s
SHA 1024 KB took 0.279 seconds, 3.58 MB/s
SHA-256 1024 KB took 0.690 seconds, 1.45 MB/s
RSA 2048 encryption took 111.17 milliseconds, avg over 100 iterations
RSA 2048 decryption took 1204.77 milliseconds, avg over 100 iterations
DH 2048 key generation 467.90 milliseconds, avg over 100 iterations
DH 2048 key agreement 538.94 milliseconds, avg over 100 iterations
STM32F2 Hardware Crypto, Normal Big Integer Math Library
AES 1024 kB took 0.105 seconds, 9.52 MB/s
ARC4 1024 KB took 0.219 seconds, 4.57 MB/s
DES 1024 KB took 0.125 seconds, 8.00 MB/s
3DES 1024 KB took 0.141 seconds, 7.09 MB/s
MD5 1024 KB took 0.045 seconds, 22.22 MB/s
SHA 1024 KB took 0.047 seconds, 21.28 MB/s
SHA-256 1024 KB took 0.690 seconds, 1.45 MB/s
RSA 2048 encryption took 111.09 milliseconds, avg over 100 iterations
RSA 2048 decryption took 1204.88 milliseconds, avg over 100 iterations
DH 2048 key generation 467.56 milliseconds, avg over 100 iterations
DH 2048 key agreement 542.11 milliseconds, avg over 100 iterations
As the above benchmarks (and chart) show, the hardware-based algorithms on the STM32 demonstrate significantly faster speeds than that of their software counterparts.
To enable STM32 hardware crypto and RNG support, define STM32F2_CRYPTO and STM32F2_RNG when building wolfSSL. For a more complete list of defines which may be required, please see the WOLFSSL_STM32F2 define in
If you would like to use wolfSSL with STM32 hardware-based cryptography or RNG, or have any questions, please contact us at facts@wolfssl.com for more information.
wolfSSL embedded SSL library
STM32: http://www.st.com/internet/mcu/class/1734.jsp
STM32F2 Standard Peripheral Library documentation: http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/USER_MANUAL/DM00023896.pdf