CCSI Officer course · Module 04 of 10
AWS Nitro Enclaves and attestation documents
How Nitro Enclaves isolate a workload from its parent EC2 instance, what the six measurements mean, how attestation documents are structured, and how AWS KMS uses them.
Learning objectives
- Describe the Nitro Enclaves isolation model and its constraints
- Map PCR0, PCR1, PCR2, PCR3, PCR4 and PCR8 to what they measure
- Read an attestation document and list what a verifier must check
- Operate the nitro-cli lifecycle safely, including the debug-mode trap
Lessons
Lesson 4.1 · 12 min
The Nitro Enclaves isolation model
Enclaves are hardened VMs carved from a parent instance, with only a vsock channel to the outside.
Lesson 4.2 · 16 min
Measurements and attestation documents
The six PCRs, the CBOR/COSE attestation document, and how to verify it.
Lesson 4.3 · 12 min
Operating enclaves with nitro-cli
Build, run, inspect and terminate enclaves, and the operational checks an officer should require.
Check your understanding
Module 4 quiz
6 questions · pass mark 80%
1.Which communication channel does a Nitro Enclave have by default?
2.Which PCR measures the IAM role assigned to the parent instance?
3.In AWS KMS, the kms:RecipientAttestation:ImageSha384 condition corresponds to which PCR?
4.What do attestation documents look like for an enclave launched with --debug-mode?
5.Which pairing does AWS recommend for flexible key policies that survive image rebuilds and instance replacement?
6.How is a Nitro Enclaves attestation document signed?
Glossary
- EIF
- Enclave Image File, the bootable image produced by nitro-cli build-enclave.
- NSM
- Nitro Secure Module, the device inside the enclave that issues attestation documents and random numbers.
- vsock
- A host-local socket family used for communication between the enclave and its parent instance.
- PCR
- Platform Configuration Register: a hash register that records measurements.