On FreeBSD, you can run any version of TrustServer for Linux in binary compatibility mode.

For example, for FreeBSD 11.1 x64: 
 - install the "linux_base-c7" package
 - add the line 'linux_enable = "YES"' to the file '/etc/rc.conf' and reboot the system
 - copy TrustServer or TrustServer64 to the folder "/compat/linux/srv" and run it