wsaesengine

A minimal openSSL engine for offloading AES symmetric cipher functions to a hardware accelerator in FPGA logic

Prerequisites

You are running linux on the Xilinx ZYNQ-7000 development board, with the necessary design instantiated in PL [link to final design goes here]
Ensure you have openSSL using the command $ openssl version. If you have lower than version 1.0.2, you must upgrade to this version.
Check out the repository using git $ git clone https://github.com/bigbrett/wsaesengine.git

Building the engine

$ cd wsaesengine
$ make

You can verify that the engine can be loaded using:

$ openssl engine -t -c `pwd`/bin/libwsaesengine.so
(/home/brett/wsaesengine/bin/libwsaesengine.so) A test engine for the ws aescbc hardware encryption module, on the Xilinx ZYNQ7000
Loaded: (wsaesengine) A test engine for the ws aescbc hardware encryption module, on the Xilinx ZYNQ7000
    [ available ]

Testing the engine

Quck test

A quick and easy test goes like this, where the output of the decryption should match the input:

$ msg="OpenSSL has poor documentation!"; key="01234567890123456789012345678901"; iv="01234567890123456"
$ epath=/path/to/libwsaesengine.so; encfile=/tmp/enc.bin
$ echo $msg | openssl enc -e -aes-256-cbc -K $key -iv $iv -engine $epath -out $encfile
    engine "wsaescbc" set.
$ openssl enc -d -aes-256-cbc -K $key -iv $iv -engine $epath -in $encfile
    OpenSSL has poor documentation!

Custom Test

A more advanced test, using a c test program, can be conducted like this (see test/wsaesengine_test.c for implementation):

$ make test
$ source test/runtest.sh

NOTE: the runtest.sh script must remain in the test directory, but should be able to be called from anywhere

OpenSSL speed test

The speed of the engine's digest computation can be tested using the built-in openSSL speed command (making sure to explicitly specify using the EVP API for the message digest)

$ openssl speed -evp aes-256-cbc -engine /path/to/libwsaesengine.so