During BSDCan 2018 the intention to update OpenSSL in base to 1.1.x branch was documented.
Intention is to update 12-STABLE to current 1.1.0 and subsequently update it to 1.1.1 when that is released.
Build log in https://keg.brnrd.eu/data/111amd64-default-openssl110/2018-06-11_10h42m37s/logs/errors/xmlsec1-1.2.25.log
Not sure if this is an error with OpenSSL 1.1 or with the port itself.
Issue is bigger than just openssl-devel.
Also fails with regular OpenSSL 1.0.2o from ports, see https://keg.brnrd.eu/data/111amd64-default-openssl/2018-06-12_14h10m42s/logs/errors/xmlsec1-1.2.25.log
Version 1.2.27 exist.
October 23 2018
The XML Security Library 1.2.27 release includes the following changes:
Added AES-GCM support for OpenSSL and MSCNG (snargit).
Added DSA-SHA256 and ECDSA-SHA384 support for NSS (vmiklos).
Added RSA-OAEP support for MSCNG (vmiklos).
Continuous build integration in Travis and Appveyor.
Several other small fixes (more details).
Current port compiles fine on 12.1 stable.