Platform: AMD SEV-SNP¶

AMD SEV-SNP (Secure Encrypted Virtualization - Secure Nested Paging) is the primary hardware root of trust for TRACE Level 2 records on AMD-based cloud instances and on-premises servers.

What AMD SEV-SNP provides¶

TRACE fields populated by SEV-SNP¶

{
  "runtime": {
    "platform": "amd-sev-snp",
    "measurement": "sha384:c9e4b1d2e3f4a5b6...",
    "rim_uri": "https://kdsintf.amd.com/vcek/v1/Milan/cert_chain",
    "firmware_version": "1.53.0",
    "nonce": "ZRVkXG1w..."
  }
}

• measurement — SHA-384 of the SNP attestation report's measurement field (the VM image digest)
• rim_uri — AMD Key Distribution Service URL for VCEK certificate chain verification
• firmware_version — SNP firmware version embedded in the attestation report
• nonce — replay-protection nonce from the attestation challenge

Verification flow¶

To verify a SEV-SNP TRACE record offline:

1. Parse runtime.rim_uri and fetch the VCEK certificate chain from AMD KDS
2. Verify the VCEK chain up to AMD's root CA (publicly available)
3. Verify the SNP attestation report signature using the VCEK certificate
4. Compare runtime.measurement against the report's measurement field
5. Confirm cnf.jwk was generated inside the enclave at that measurement

# cMCP does steps 1-5 automatically and embeds the result in the TRACE record
agentrust-trace verify-hardware session.trace.json \
  --platform amd-sev-snp \
  --check-rim

Supported cloud instances¶

On-premises deployment¶

For on-premises SEV-SNP (e.g., Supermicro H13 with EPYC Genoa), Opaque ships the verifier with the platform — same cryptographic guarantees as cloud deployments, no cloud attestation service dependency. See agentrust-io/cmcp for the Helm chart.

Example record¶

See examples/amd-sev-snp.json for a complete TRACE Level 2 record from an AMD SEV-SNP deployment.