Files
archy/core/archipelago/src/federation/mod.rs
T
archipelagoandClaude Opus 5 c0cfc72a05 fix(security): peers must not be able to grant themselves Trusted
Reported: "peers seem to be slipping into trusted status somehow which is
absolutely terrible for security". Two independent fail-open paths, both
granting Trusted with no operator decision anywhere in the loop.

1. federation.peer-joined is UNAUTHENTICATED (middleware's no-session
   list — federated peers call it over Tor without cookies) and reachable
   on /rpc/v1, which is peer-allowed. It does verify an ed25519 signature,
   but against THE PUBKEY THE CALLER SUPPLIED, so it proves the caller
   holds its own key and nothing about whether we ever invited it. A join
   presenting no invite_token fell through to

       None => TrustLevel::Trusted.min(claimed_trust)

   and claimed_trust itself defaults to Trusted when the field is absent.
   So anything able to reach the node could generate a keypair, omit the
   token, and be recorded as Trusted. Now capped at Observer: an invite
   WE minted is the only path to Trusted. `min` is kept so a peer's own
   lower claim is still honoured — this can only ever reduce trust.

2. merge_transitive_peers added every peer advertised by a Trusted source
   as Trusted. That makes trust viral rather than transitive-by-one-hop:
   the merged node is itself synced with, its peers merged in turn, so a
   single invite anywhere in the graph eventually marked the entire graph
   Trusted on every node. Now Observer — which is what this feature's own
   spec always said. NodeStateSnapshot.federated_peers is documented as
   "adds them as Observers on her side… doesn't auto-promote Observer-via-
   Bob to Trusted". The code contradicted the comment directly above it.

Observer is deliberate rather than Untrusted: the merge exists for
routing, and Observer still passes the `!= Untrusted` gates that
federation, DWN and messaging actually check, so a legacy peer degrades
instead of breaking. Per the operator's decision, existing peers are NOT
auto-demoted — silently rewriting live trust relationships across the
fleet would be worse than the bug.

Instead they are made auditable: FederatedNode.trust_source records WHY a
level was granted (invite | uninvited-join | transitive-merge | manual).
It deliberately has no default provenance — None means "recorded before
this existed", which is exactly the population worth reviewing.

The one failing test was asserting the vulnerable behaviour
(merge_transitive_peers_skips_source_and_local_node expected Trusted); it
now asserts the security property and says why, so the escalation cannot
be reintroduced by making a test go green.

Verified: 42/42 federation tests, cargo check --all-targets clean.

Still open, tracked in .planning/RELEASE-1.7.121-TASKS.md: surface
trust_source in the UI, and require the node password to grant Trusted.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-08-03 10:31:16 -04:00

28 lines
1.2 KiB
Rust

//! Node federation: trusted multi-node clusters with state sync.
//!
//! Nodes federate by exchanging invite codes containing DID + onion address.
//! Trust is bilateral — both sides must agree. Federated nodes periodically
//! sync container status, health metrics, and availability.
mod invites;
pub mod pending;
mod storage;
mod sync;
mod types;
// Re-export all public items so `crate::federation::*` continues to work.
pub use invites::{accept_invite, create_invite, parse_invite};
// Crate-internal: used by the periodic federation auto-sync to re-assert
// membership to peers that don't list us back (asymmetry self-heal).
pub(crate) use invites::notify_join;
// Crate-internal: peer-joined resolves the granted trust level by matching
// the acceptor's invite_token against our stored outgoing invites.
pub(crate) use storage::load_invites;
#[allow(unused_imports)]
pub use storage::{
add_node, fips_npub_for_onion, load_nodes, load_removed_dids, record_peer_transport,
record_sync_result, remove_node, save_nodes, set_trust_level, update_node,
};
pub use sync::{build_local_state, deploy_to_peer, sync_with_peer, sync_with_peer_by_did};
pub use types::{AppStatus, FederatedNode, NodeStateSnapshot, TrustLevel, TrustSource};