Recompute SHA-256 hash-chain and validate HMAC signatures for all audit events.
Export immutable audit trail as JSONL (newline-delimited JSON). Includes hash-chain, HMAC signatures, and RFC 3161 anchors.
Verify offline: openssl dgst -sha256
Anchor current chain head to a public Timestamp Authority (FreeTSA/DigiCert). Proves existence at a specific moment in time.
Verify: openssl ts -verify
NIST SP 800-92
Log Management
FIPS 198-1
HMAC Signatures
FIPS 180-4
SHA-256 Hash
RFC 3161
Timestamp Protocol
US FRE 902(13-14)
Digital Evidence
IRS Rev Proc 98-25
Record Retention