Because clouds are based on virtualization as well, I recommend CloudSim in accordance with the ResearchGate thread at https://www.researchgate.net/post/Is_there_any_tool_or_simulator_for_cloud_security
You can have a look on sVirt (http://selinuxproject.org/page/SVirt) from redhat. Many other solutions are based on TXT (Trusted eXecution Technology) from Intel.
I work with VMware Products, they used their own vSafe API, but it's not longer supported: http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=2058911
Looks like vShield Endpoint is still active, it was run over the vSafe, it has its own REST API: http://www.vmware.com/products/vsphere/features/endpoint.html