jailkit を Homebrew, apt, MacPorts でインストール

プロジェクトリンク

• ホームページ
• リポジトリ
• 上流ドキュメント
• パッケージマネージャページ

コマンドとエイリアス

• jk_check
• jk_chrootlaunch
• jk_chrootsh
• jk_cp
• jk_init
• jk_jailuser
• jk_list
• jk_lsh
• jk_socketd
• jk_uchroot
• jk_update

プロジェクトの歴史

The project page and man page credit Olivier Sessink and carry copyright years beginning in 2003. Jailkit was built to automate repeated chroot setup tasks, including copying binaries and libraries into a jail, limiting commands through a restricted shell, checking jail integrity, and forwarding logs from inside a jail.

The project has stayed intentionally narrow. The homepage emphasizes stable, security-focused behavior: utilities abort when configuration or environment checks are not secure, and syslog messages explain what failed. Maintenance releases in 2019 and 2021 focused on Python 3 compatibility, `jk_update`, `jk_init`, and man-page cleanup rather than broad feature expansion.

採用の歴史

The homepage states that Jailkit is used in network security appliances, large enterprise and ISP internet servers, smaller companies, and private deployments for securing CVS, SFTP, shell, and daemon processes. Homebrew API data available during this enrichment recorded 142 installs over 365 days, which matches a specialized system-administration tool with long tail usage.

使われ方

Administrators use Jailkit to initialize a jail, copy only the commands and libraries needed for a task, move users into the jail, restrict allowed commands through `jk_lsh`, and check common jail security mistakes with `jk_check`. The man page stresses that writable system directories, setuid programs, and root privileges inside a jail can defeat the intended isolation.

パッケージ好きにとっての重要性

Jailkit matters to package nerds because it packages institutional Unix hardening lore into named commands: `jk_init`, `jk_cp`, `jk_chrootsh`, `jk_lsh`, `jk_jailuser`, `jk_check`, and friends. It is not glamorous, but it turns chroot from a hand-built directory-tree ritual into repeatable system administration.

タイムライン

• 2003: Project copyright and man-page history begin under Olivier Sessink.
• 2019: Jailkit 2.21 added full Python 3 compatibility and removed the long-deprecated `jk_addjailuser` utility.
• 2021: Jailkit 2.22 fixed Python 3 compatibility in `jk_update` and improved `jk_init.ini` defaults.
• 2021: Jailkit 2.23 fixed `jk_init` edge cases and cleaned up man-page locations.
• 2026: The project page documented non-exposure to CVE-2026-23268/CVE-2026-23269 because Jailkit exits when required system calls fail or are not permitted.

Related projects

• Jailkit is related to the Unix `chroot(2)` facility, OpenSSH restricted SFTP setups, limited shells, rsync/scp/CVS jail deployments, and OS-level isolation mechanisms. Unlike containers, its focus is small, explicit filesystem jails for accounts and daemons.

ソース

• https://cvs.savannah.nongnu.org/viewvc/jailkit
• https://formulae.brew.sh/api/formula/jailkit.json
• https://olivier.sessink.nl/jailkit/
• https://olivier.sessink.nl/jailkit/jailkit.8.html
• https://savannah.nongnu.org/projects/jailkit