StrongSwan is an OpenSource IPsec implementation for Linux. This SlackBuild enables configure options which are known to compile without issue on a stock Slackware 14.2 system. These options provide additional functionality and increase this packages ability to inter operate with various vendor implementations. Unwanted and/or unnecessary plugins can be disabled a run-time via the 'load' flag in /etc/strongswan.d/charon/*.conf files. The following configure options are enabled by default: --enable-shared --enable-silent-rules --enable-openssl --enable-unity --enable-curl --enable-sql --enable-sqlite --enable-cmd --enable-af-alg --enable-gcrypt --enable-aesni --enable-sha3 --enable-files --enable-lookip --enable-eap-mschapv2 --enable-eap-tls --enable-eap-ttls --enable-eap-radius --enable-ext-auth --enable-xauth-eap To disable the above options set the environment variable CONFIG_OPTS to the empty string when calling this SlackBuild. Example: env CONFIG_OPTS=" " sh ./strongswan.SlackBuild To override the defaults options set CONFIG_OPTS to your desired set of configure options. Example: env CONFIG_OPTS="--enable-openssl --enable-unity" sh ./strongswan.SlackBuild To add to the default options without overwriting them set the EXTRA_CONFIG_OPTS environment variable. Example: env EXTRA_CONFIG_OPTS="--enable-socket-dynamic --enable-dhcp" sh ./strongswan.SlackBuild The list of available options and their descriptions are available here: https://wiki.strongswan.org/projects/strongswan/wiki/Autoconf