OpenSSL 1.1 make many internal structures opaques and Ike required some updates OpenSSL 1.1 backward compatibility guide
# Get latest sources
wget https://www.shrew.net/download/ike/ike-2.2.1-release.tbz2
tar xvjf ike-2.2.1-release.tbz2
# Patch
wget https://raw.githubusercontent.com/hgomez/ike-patch-for-openssl-1.1/master/ike.patch
cd ike
patch -p1 <../ike.patch
# Make
cmake -DCMAKE_INSTALL_PREFIX=/usr -DQTGUI=NO -DETCDIR=/etc -DNATT=YES
make
# Install
sudo make install