mrwulf
7c717d03fc
A transparency log without split-view defense is just a signature with extra steps: the provider could serve one tree to the agent and another to the world, or roll the log back, and standalone receipt verification would never notice. The primitives (RFC 9162 consistency proofs) were already implemented and correct; this closes the loop on the AGENT side. - src/pacta/sthstore.py: a local STH pin store. Unknown log -> pin (trust-on-first-use, recorded as such). Same tree size -> the root must match the pin byte-for-byte; a mismatch is named EQUIVOCATION and is a hard rejection. Larger tree -> a consistency proof FROM THE PINNED SIZE is required and verified before the pin advances (receipts already embed a from-previous anchor; the anchor's root is itself checked against the pin so a lying anchor cannot bridge a split view). Smaller tree -> LOG ROLLBACK, hard rejection. - Freshness policy: --max-sth-age-seconds rejects stale (or future-dated) tree heads - an old-but-valid STH can hide later entries. - Wired into receipt-verify, claims, and agent (--sth-store, --consistency-proof, --max-sth-age-seconds); evidence records the pin action; any accountability failure fails the receipt closed. - Provider: log-consistency --from-size N (serve proofs for pinning agents whose pin is older than the receipt's embedded anchor) and log-audit (monitor self-check: recompute the tree, verify the stored STH and per-entry leaf hashes). Live drill in this commit's validation: pin-on-first-use -> matched -> grown-with-proof advance -> a real forged same-size split view REJECTED with the equivocation diagnostic -> freshness rejection -> clean self-audit. tests/test_sthstore.py covers pin/match/equivocation, growth-without-proof, lying consistency anchors, rollback, freshness. 45/45 tests green. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> |
||
|---|---|---|
| .. | ||
| src/pacta_provider | ||
| pyproject.toml | ||
| README.md | ||
PACTA Proof Check Provider
This nested project is a prototype third-party proof-checking service. It reuses host Lean/Aeneas infrastructure, runs portable PACTA replay/audit checks, and emits signed attestation certificates.
It does not modify anything outside this repository. It may read configured toolchains such as /Users/oho/GitClone/ClaudeCodeProjects/your-lean-project/aeneas-toolchain/env.sh.
It can also maintain a local transparency log. The log is an RFC 9162-style Merkle accumulator over signed attestations. It emits Signed Tree Heads with Ed25519 today and records an ML-DSA/FIPS 204 signature slot as unavailable unless a real backend is present. Agents that require both signatures must reject such receipts.
Commands
PYTHONPATH=src:provider/src python -m pacta_provider discover
PYTHONPATH=src:provider/src python -m pacta_provider init-key --key-dir provider/state/demo-provider
PYTHONPATH=src:provider/src python -m pacta_provider check \
--config examples/repos.yaml \
--repo-name dalek-ed25519-verified \
--repo repos/dalek-ed25519-verified \
--provider local-pacta-provider \
--private-key provider/state/demo-provider/provider.ed25519.key \
--public-key provider/state/demo-provider/provider.ed25519.pub \
--out provider/out/dalek.attestation.yaml
Transparency log:
PYTHONPATH=src:provider/src python -m pacta_provider log-init \
--log-dir provider/state/transparency-log \
--provider local-pacta-provider \
--public-key provider/state/demo-provider/provider.ed25519.pub
PYTHONPATH=src:provider/src python -m pacta_provider log-append \
--log-dir provider/state/transparency-log \
--attestation provider/out/dalek.attestation.yaml \
--private-key provider/state/demo-provider/provider.ed25519.key \
--public-key provider/state/demo-provider/provider.ed25519.pub \
--out provider/out/dalek.receipt.yaml
PYTHONPATH=src:provider/src python -m pacta_provider log-sth \
--log-dir provider/state/transparency-log \
--private-key provider/state/demo-provider/provider.ed25519.key \
--public-key provider/state/demo-provider/provider.ed25519.pub
The resulting certificate can be consumed by pacta with --attestation, --trust-attestation-provider, and --attestation-public-key.
The receipt can be consumed with --transparency-receipt, --transparency-log-public-key, and --require-transparency-receipt.
The private key must remain provider-side. Downstream agents only need the public key, the inclusion receipt, and a policy decision that the provider name/log key is trusted.