proto-blue-repo

AT Protocol repository primitives -- Merkle Search Trees, CAR files, block storage.

Install

[dependencies]
proto-blue-repo = "0.3"

Exports

• MstNode
• BlockMap, CidSet
• blocks_to_car, read_car, read_car_with_root
• RepoError

Usage

use proto_blue_repo::{MstNode, BlockMap, blocks_to_car, read_car};
use proto_blue_lex_data::LexValue;
use proto_blue_lex_cbor::cid_for_lex;

let cid = cid_for_lex(&LexValue::String("test".into())).unwrap();
let mst = MstNode::empty();
let mst = mst.add("app.bsky.feed.post/abc123", cid.clone()).unwrap();
assert_eq!(mst.leaves().len(), 1);

Testing

Standard unit and round-trip tests live alongside the modules. The proof pipeline additionally has property-based and fuzz coverage:

• tests/property_tests.rs — seven proptest cases over the covering_proof / verify_proof pair:
  • proof_verifies_present_key — soundness for present keys
  • proof_rejects_wrong_value — completeness against wrong-value claims
  • proof_verifies_absence_for_missing_key — absence proofs for non-members
  • block_removal_never_produces_silent_false_accept — removing any block from a valid proof either still verifies (block was redundant) or returns Err(MissingBlock); never Ok(false). This is the strict-superset / overestimate invariant.
  • extra_blocks_do_not_change_verdict — verifier ignores noise blocks
  • tamper_cannot_force_wrong_value_acceptance — no proof-byte mutation paired with a wrong-value claim yields Ok(true)
  • covering_proof_is_superset_of_each_directional_proof — structural: covering = key ∪ left-sibling ∪ right-sibling
• proto-blue/fuzz/fuzz_targets/proof_construct_verify.rs — adversarial mutation (drop / flip / insert) of proof block-maps; asserts no silent acceptance of forged-value claims regardless of mutation.

The audit's predicted "insufficient-blocks" bug class did not surface — under deletion the verifier returns Err(MissingBlock) correctly rather than a silent Ok(false).

License

Licensed under MIT OR Apache-2.0.

Part of the proto-blue AT Protocol SDK for Rust.