BrivoraProof Protocol Specification

This document specifies the BrivoraProof format at the byte level, enabling any implementation in any programming language to generate and verify governance proofs without depending on Brivora software.

Proof structure

A BrivoraProof is a structured object with the following fields, serialized as CBOR (RFC 8949) for wire format and JSON for human-readable interchange.

Field	Type	Size	Description
version	string	3 bytes	Protocol version ("1.0")
timestamp	string	24 bytes	ISO 8601 UTC timestamp
subject	string	variable	DID of the evaluated system
verifier	string	variable	DID of the verifier
governance_policy	bytes	32 bytes	SHA-3-256 hash of governance pack
system_state_hash	bytes	32 bytes	SHA-3-256 hash of system state
fidelity_score	float64	8 bytes	Compliance score (0.0-1.0)
evaluation_result	uint8	1 byte	0=PASS, 1=FAIL, 2=PARTIAL
evidence_chain	bytes[]	32 x N bytes	Merkle tree leaf hashes
merkle_root	bytes	32 bytes	SHA-3-256 Merkle root
signature	object	variable	See signature format below
public_key	bytes	variable	Verifier’s public key
previous_proof	bytes	32 bytes	Previous proof hash (optional)

Hash algorithm

All hashes use SHA-3-256 (FIPS 202). Input is the canonical CBOR encoding of the field value.

Signature format

interface ProofSignature {
  pqc: Uint8Array;            // ML-DSA-65 signature (~3,300 bytes)
  classical?: Uint8Array;     // Ed25519 signature (64 bytes)
  algorithm: string;          // 'hybrid-pqc-v1' or 'pqc-only-v1'
}

The signed message is the merkle_root bytes.

Version negotiation

Verifiers must check the version field before processing. Unknown versions must be rejected. Version "1.0" is the only currently defined version.