Signing¶
Ed25519 and ML-DSA-65 (post-quantum) signing for agent manifests. See ADR-0005 for the signature design.
Key generation¶
dataclass ¶
Signing¶
Signs manifest dicts with Ed25519 (RFC 8032, deterministic).
For production use on high-value keys, prefer a HSM implementation of hedged signing (draft-irtf-cfrg-det-sigs-with-noise) to protect against fault attacks on the deterministic nonce derivation.
Return a signature block dict suitable for ManifestSignature.
Verification¶
Verifies Ed25519 signatures using OpenSSL's cofactorless equation.
Verify signature_value over manifest_dict's signed fields.
Raises:
| Type | Description |
|---|---|
InvalidSignature | Verification failed or wrong length. |
ValueError | Signature string contains non-URL-safe base64 characters. |
Signing internals¶
Return the RFC 8785 canonical bytes that are signed.
Extracts only the SIGNED_FIELDS subset from manifest_dict and canonicalizes the result. Fields absent from the manifest are omitted (null-exclusion already applied by canonicalize's exclude_none default).
Normalization rule (spec Section 3.6, ADR-0006 as amended): the value of hitl_record.approvals is normalized to [] before canonicalization. The HITL requirement itself stays tamper-evident under the issuer signature while approvals attach post-issuance without re-signing; each approval is authenticated separately by its own approval_signature.
This function is the single source of truth for the pre-image - both signers and verifiers MUST call this function to guarantee identical byte sequences.
module-attribute ¶
SIGNED_FIELDS: tuple[str, ...] = ('@context', '@type', 'manifest_id', 'previous_manifest_id', 'agent_id', 'version', 'min_verifier_version', 'issued_at', 'expires_at', 'issuer', 'crypto_profile', 'artifacts', 'delegation_chain', 'hitl_record', 'prior_transparency_log_entry', 'log_retention', 'data_scope', 'operational_lifecycle')
Canonicalisation¶
Return RFC 8785 canonical JSON bytes for obj.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
obj | Any | Any JSON-serializable Python value. | required |
exclude_none | bool | When True (default, per spec Section 4.3), mapping entries whose value is None are omitted from the output. Set to False only when verifying round-trips with external producers that include explicit null fields. | True |
Returns:
| Type | Description |
|---|---|
bytes | UTF-8 encoded bytes with no trailing newline. |
Raises:
| Type | Description |
|---|---|
TypeError | If obj contains a type that cannot be serialized. |
ValueError | If a float value is NaN or Infinity, or nesting exceeds the maximum depth. |
Canonicalize obj and return a prefixed hex digest.
Returns:
| Type | Description |
|---|---|
str | String in HashValue format: |
str |
|