TruFaaS - Trust Verification Framework for FaaS

As the Function as a Service (FaaS) model on cloud grows increasingly popular, more mission critical applications have begun to adopt it as a development paradigm. It is essential for such applications to trust its component functions, as they heavily rely on the functions performing as intended. While FaaS platform security is well-researched, there has been little attempt to address the issue of trust, which pertains to ensuring that function invokers use the original function deployed by the provider. To address trust concerns in FaaS, we present TruFaaS, a novel trust verification framework for FaaS which enables function invokers to verify the trust of functions deployed on a FaaS platform. We present a generic framework architecture which can be incorporated into any open source FaaS platform. The framework performs trust calculation, storage and verification. The trust verification mechanism can detect unauthorized modification of a function. TruFaaS also has a trust protocol to communicate trust of functions to function invokers. We implement TruFaaS on the open source FaaS platform Fission to demonstrate its effectiveness practically. Our implementation performs with \(\mathtt {<}\) 4% overhead for function deployment and \(\mathtt {<}\) 20% for function invocation.