xmlsec1 from Cloud:OpenStack:Upstream:Queens:SLE_12_SP3 project
Select Your Operating System
Add repository and install manually
For SLE 12 SP3 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/Cloud:OpenStack:Upstream:Queens:SLE_12_SP3/SLE_12_SP3/Cloud:OpenStack:Upstream:Queens:SLE_12_SP3.repo zypper refresh zypper install xmlsec1