tari-project / tari / 27135121061

60%

Build Type

push

github

Committed by web-flow

Commit Message

fix(base_node): reject duplicate validator node registrations within a block (#7870)

Description
---
Adds a chain-linked validation rule
(`verify_no_duplicate_validator_node_registrations`) that rejects a
block body containing more than one validator node registration for the
same `(sidechain id, validator node public key)`, with a new
`DuplicateValidatorNodeRegistration` validation error.

Motivation and Context
---
A validator node registration UTXO is only checked against the validator
node set as of the **parent** block (`check_validator_node_registration`
→ `validator_node_exists`). That check cannot see other registrations in
the **same** block body, and `contains_duplicated_outputs` only compares
whole-output equality. So two outputs registering the same validator
node public key (with different commitments) both pass validation.

They then collide at commit time: the validator node set is keyed by
sidechain id + public key and inserted with LMDB `NO_OVERWRITE`
(`ValidatorNodeStore::insert`), so the second insert returns `KeyExists`
and the block is aborted during the DB write (`reorganize_chain`
restores the chain and returns an error — see the "this should typically
never happen unless there is a bug in the validator" comment there)
instead of being rejected cleanly during validation.

This makes the invariant ("at most one active registration per validator
node") an explicit validation rule rather than an accidental side effect
of the storage layer. The new error is classified as a long ban, so an
offending block is recorded as bad rather than silently retried. The
check runs before commit on both the block path
(`BlockBodyFullValidator::validate`) and the mempool transaction path
(`TransactionChainLinkedValidator`).

Note: this does not change the canonical chain — such blocks were
already uncommittable; it converts a commit-time abort into a clean
validation rejection.

How Has This Been Tested?
---
- New unit tests: distinct registration... (continued)

Coverage Stats

41 of 45 new or added lines in 2 files covered. (91.11%)

29 existing lines in 9 files now uncovered.

71978 of 117403 relevant lines covered (61.31%)

222669.0 hits per line