housecarl/CHANGELOG.md

Changelog

All notable changes to Housecarl are documented here. The format follows Keep a Changelog, and versions follow Semantic Versioning.

[Unreleased]

The first version of Housecarl, a firewall manager for nftables, built the way Jarl and Steward are.

Added

• Zones, address sets and services: interfaces grouped by what they connect to (wildcards like incusbr*; external zones face the internet); sets of IPv4 and IPv6 addresses, prefixes and ranges, mixed; ports and ICMP types by name, with twenty built in (docs/rules.md).
• Rules in four chains (input, forward, output, and early, before connection tracking), in order, matching by zone, address, service, family, connection state and status, days and hours, a rate (also per source address), and a connection count; accept, drop, reject (ICMP or TCP reset) or log. Raw nftables rules for the rest.
• IPv4 and IPv6 together: one rule becomes the nftables rules each family needs.
• NAT: port forwards as one object (DNAT, the forward accept, hairpin NAT, and optionally an IPv6 pinhole to a host's own port); source NAT (masquerade or an address; NAT66 on request); redirects to the firewall (docs/nat.md).
• Built-ins, each switchable: loopback, established connections, invalid packets, ICMPv6 (RFC 4890), ping from internal zones, DHCPv6 client replies, antispoofing with your own prefixes, MSS clamping, and a flowtable fast path.
• Changes checked twice and applied atomically: validation of the whole configuration with stable problem codes (docs/validation.md), then nft -c, then one nft -f transaction that replaces Housecarl's own table, inet housecarl, and nothing else. Dynamic sets' entries and the counters carry across.
• Probation: a change made over the network rolls itself back unless confirmed within two minutes (hc confirm, a banner in the web UI); changes through the local socket are kept at once; a restart rolls back what was pending. No rule is forced to keep SSH or the web UI open.
• At boot: the confirmed ruleset is loaded by housecarl-ruleset.service before the network comes up, without housecarld. An empty configuration applies nothing.
• Hits and the log: packet and byte counters for every rule, NAT rule, built-in and policy; packets logged by rules and policies, read from netlink log group 4171 (hc log -f, the Log page).
• Dynamic sets whose entries expire by themselves, changed through their own API with tokens that may be limited to one set (sets:write:guests).
• Import of an existing nftables ruleset (hc import): rules keep their order, defines name the sets, DNAT becomes port forwards, what can't be translated stays as raw rules, with notes; hc takeover deletes the old table, on probation (docs/import.md).
• The hc CLI, the REST API and the web UI (dashboard, rules per chain with hits and reordering, NAT, zones, sets, services, the log, settings, import, history with undo), with users, roles, scoped API tokens, sessions, the audit log, and the web UI's certificate from Let's Encrypt through Jarl, as in Steward.
• Packaging: Debian packages housecarl and housecarl-cli, a systemd unit whose only privilege is CAP_NET_ADMIN, daily backups.
• The Housecarl logo: a carved Nordic doorway in Jarl's blue, with a simplified version for small sizes, lighter on dark backgrounds; and a HOUSECARL wordmark in Jarl's and Steward's angular letters.