chio-did

Self-certifying did:chio identifiers and DID Document resolution. The method-specific identifier is the lowercase hex form of an Ed25519 public key already used by Chio agents and operators, so basic resolution needs no registry lookup. The resolving environment may attach optional receipt-log and passport-status service endpoints.

Responsibilities

Derive a canonical did:chio:<64-hex> identifier from an Ed25519 PublicKey and parse it back (DidChio, FromStr, Display).
Resolve a DidChio into a W3C-shaped DidDocument with one Ed25519 verification method, with no network or registry lookups.
Validate and attach resolver-provided service endpoints (DidService), rejecting anything that is not a well-formed https URL.
Reject non-Ed25519 key material and malformed method-specific identifiers.

Public API

DidChio - parses, renders, and resolves a did:chio identifier. from_public_key/try_from_public_key, as_str, verification_method_id, public_key_multibase, resolve, resolve_with_options; implements Display, FromStr, TryFrom<PublicKey>.
DidDocument, DidVerificationMethod, DidService - the resolved document and its parts (serde::Serialize/Deserialize, DID-spec field names).
DidService::new / ::receipt_log / ::passport_status - validated service-endpoint constructors; RECEIPT_LOG_SERVICE_TYPE and PASSPORT_STATUS_SERVICE_TYPE name the two known service types.
ResolveOptions - builder for the services attached during resolution.
resolve_did_arc - parse-and-resolve convenience over a raw did:chio:... string.
DidError - the crate's fail-closed error enum.

Usage

use chio_core::Keypair;
use chio_did::{DidChio, DidService, ResolveOptions};

let keypair = Keypair::from_seed(&[7u8; 32]);
let did = DidChio::from_public_key(keypair.public_key())?;

let options = ResolveOptions::default().with_service(
    DidService::receipt_log(&did, 0, "https://trust.example.com/v1/receipts")?,
);
let document = did.resolve_with_options(&options);
assert_eq!(document.id, did.to_string());

Feature flags

Flag	Effect
`fuzz`	Enables `chio_did::fuzz` (`fuzz_did_resolve`), the libFuzzer entry point. Off by default; pulls in `arbitrary` and `serde_json`. Enabled only by the standalone `fuzz` workspace.

Testing

cargo test -p chio-did