vechain/thor v2.5.1

on GitHub

v2.5.1 carries robustness improvements across the P2P layer, block processing, the transaction pool and the public/admin APIs, together with a handful of API and SDK fixes. Most changes are internal; the user-visible ones are listed below.

What's Changed

Hardening & Robustness

These changes tighten resource bounds and failure handling throughout the node. They do not change consensus rules: every bound is sized above what a valid block can hold under the current 40M block gas limit.

• Networking: new blocks received from a peer are handed off through a per-peer mailbox instead of being processed on the peer's read loop. Transaction broadcast now uses a single bounded queue and writer per peer. Future-block cache entries are capped per peer and bound to their header. Inbound connection attempts are rate-limited per source (one per 30s for a non-LAN IPv4 address or IPv6 /64 prefix), matching go-ethereum (#1699). Internal consistency fixes in the discv5 topic table.
• Block decoding: stricter bounds while decoding block headers and bodies (header field widths, total clause count per block). The existing per-tx and per-block limits are now collected in thor/gas_limits.go so they are sized against one definition of the block gas limit. The packer respects the same bounds and treats an exhausted clause budget as a full block.
• Adaptive gas limit: the bandwidth-derived block gas-limit target, which packers use by default, is now floored at 30M (ceiling unchanged at 40M).
• Transaction pool: transactions submitted through the API are now admitted under the same caps as transactions received from peers. The previous behaviour (local tier: no max lifetime, exempt from trimming, re-announced on every wash) is available behind the new --api-local-tx-privileges flag, off by default. Fixed a metric double-count when the same transaction is added concurrently (#1678).
• Node: the node's highest-seen block number now advances when a block is persisted rather than after BFT commit.
• API
  • Responses are written in bounded chunks with a 10s stall timeout, enforced at the connection level so it covers every reply including 404/405 and CORS preflight; a client that stops reading is disconnected (#1699). WebSocket subscription writes (frames, ping, close) carry the same deadline.
  • Requests that hit the API timeout now return 503 (request timed out); requests whose client went away return 499 (client closed request) instead of 500.
  • POST /accounts/* batch calls are capped at 2500 clauses (400 above that); a null request body is rejected with 400.
  • debug tracing: a new --api-trace-data-max-size flag (default 2.5 MiB) bounds the call input/output data retained per trace; the clause replay and custom JS tracer result collection stop as soon as the request deadline fires or the client disconnects.
  • Admin API: state-changing routes (POST/PUT/PATCH) now require Content-Type: application/json and answer 415 otherwise. Update any scripts that post form-encoded bodies.

Protocol

• Legacy transaction reward alignment (#1679). For legacy (type 0x00) transactions after GALACTICA, the validator reward is now derived from the gas price the signer is charged. This is a refinement of the VIP-251 legacy fee mapping and is shipped without a fork gate.
  • Mainnet / testnet: no effect and no resync; results are identical for every historical transaction on both networks.
  • Solo / custom networks: chains that use the default genesis base-gas-price and contain legacy transactions with proved work may replay with different receipts. Regenerate such chains from genesis after upgrading.

API Fixes

• topics for LOG0 events is now [] instead of null in expanded blocks and subscription messages (#1682).
• order in /logs/event and /logs/transfer filters is case-insensitive; values other than asc/desc are rejected with 400 (#1684).
• Event filters without an address and spanning fewer than 100,000 blocks are evaluated by a sequence-range scan instead of the topic index, which is substantially faster for narrow topic-only queries (#1693).

Observability

• New metrics: comm_block_mailbox_overwrite_counter, api_non_json_request_body_count{name,media_type}.
• bandwidth updated trace logs are throttled to significant changes (#1691).

thorclient/bind

• Transactions default to dynamic-fee when the best block carries a base fee, with maxFeePerGas = 2·baseFee + tip; gas is estimated by simulation; DeployContract simulates first and does not send on revert or VM error (#1689).

CI, Build & Dependencies

• Bumped the go-ethereum fork for an RLP decoding improvement(#1697).
• disco bumped to 1.0.7; the two new flags are documented in docs/command_line_arguments.md (#1698).
• Daily check of the release signing subkey expiry (#1677).
• Test isolation fixes and Go 1.26 idioms (#1680, #1687, #1688, #1692); CI tidy-ups (#1686, #1696).

Contributors

• @libotony
• @otherview
• @cristidas

Full Changelog: v2.5.0...v2.5.1