TEE / Confidential Computing

This runs the addition example in encrypted mode through the Propeller Kubernetes operator, protecting code and data from the host OS.

Prerequisites

The operator must be deployed and a Proplet registered. Follow the end-to-end example first.

Proplet Configuration

TEE mode requires a Key Broker Service URI and attestation agent config:

kubectl patch proplet k8s-proplet --type=merge -p '{"spec":{"k8s":{"env":{"kbsUri":"http://kbs.example.com:8082","aaConfigPath":"/etc/default/proplet.toml"}}}}'

Note: This requires real TEE hardware (Intel TDX or AMD SEV-SNP). Without it, the proplet's stub HAL path will be exercised but no real attestation will occur. The proplet logs will show TDX=false, SEV=false at startup.

kbsUri accepts https:// for a TLS-enabled KBS. The PropletSpec only sets the PROPLET_KBS_URI/PROPLET_AA_CONFIG_PATH env vars — it doesn't mount files — so the file at aaConfigPath (containing [token_configs.kbs] with url and the inlined cert PEM, see Configure Proplet for TEE mode) must already exist in the proplet image or node filesystem before the pod starts.

Build the WASM Module

cd propeller
make addition

Apply the Task

The key difference is encrypted: true:

WASM_B64=$(base64 -w0 propeller/build/addition.wasm)
kubectl apply -n propeller-workloads -f - <<EOF
apiVersion: propeller.propeller.absmach.eu/v1
kind: Task
metadata:
  name: tee-addition-example
spec:
  name: tee-addition-example
  functionName: main
  file: "${WASM_B64}"
  encrypted: true
  inputs:
    - "10"
    - "32"
  propletSelector:
    propletId: "k8s-proplet"
EOF

Watch and Verify

kubectl get task tee-addition-example -n propeller-workloads \
  -o jsonpath='{.status.results}'

Expected result: 42

Reference