Agent contact_ip needs to allow hostnames

[tuminoid]

Use-case

Keylime agent is in k8s cluster, but Verifier/Tenant/Registrar is outside k8s cluster. Traffic from Verifier to Agent goes via k8s Ingress, which needs to map URL to correct Agent per UUID. Agent is hence reachable at https://agent-<uuid>.cluster.local/ ...

Issue

There is parse_ip called to parse the contact_ip here:

rust-keylime/keylime-agent/src/config.rs

Line 859 in 56a6159

let contact_ip = parse_ip(config.agent.contact_ip.as_ref())?.to_string();

so Agent cannot set hostname such as agent-<uuid>.cluster.local as its contact_ip, meaning it cannot register itself with an address that can be routed back.

xref: https://cloud-native.slack.com/archives/C01ARE2QUTZ/p1727792733885549
@maugustosilva @mheese