bootstrap: create an admin user and make the root door role-aware
Adds a non-root admin user (sudo group, never docker, NOPASSWD sudo, key-only) on every role, with its authorized_keys seeded ONCE from root's at creation — live proof the operator holds the private key. --admin-key composes an explicit key with the seed. Adds --lock-root (PermitRootLogin no), role-gated: refused (exit 2) on control-plane (Coolify self-SSH) and workload (needs Coolify's experimental non-root mode rig doesn't provision), allowed on runner. Before closing root's door it verifies the admin is reachable (account not expired, real shell, sane authorized_keys, sudo -n true, sshd -T -C resolution permits the login); any failure leaves the door open and says why. The PermitRootLogin no drop-in is 00-rig-root.conf, sorting BEFORE 00-rig.conf so first-wins sshd_config semantics actually apply it, installed with the same validate-before-restart + sshd -t + rollback + sshd -T effective-assert dance as the base hardening. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
This commit is contained in:
Claude
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3 changed files with 420 additions and 12 deletions
112
README.md
112
README.md
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@ -35,12 +35,116 @@ rig bootstrap runner --hostname my-ci-box
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- `--ts-tag <tag>` — tailnet tag to advertise (default: `tag:server`;
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the `runner` role defaults to `tag:ci` instead, and **refuses**
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`tag:server` outright — see below)
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- `--admin-user <name>` — non-root admin account to create on every role
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(default: `admin`; **refuses `root`**). See [The admin user](#the-admin-user).
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- `--admin-key <pubkey>` — an extra public key to add to the admin account at
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creation, composed with the seed-from-root below (optional).
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- `--lock-root` — close root's SSH door (`PermitRootLogin no`). **Role-gated**:
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refused on `control-plane` and `workload`, allowed on `runner`. See
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[The role-aware root door](#the-role-aware-root-door).
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What it does: installs `curl ca-certificates unattended-upgrades` (and
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enables periodic unattended upgrades); writes an sshd hardening drop-in
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What it does: installs `curl ca-certificates unattended-upgrades sudo openssh-server`
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(and enables periodic unattended upgrades); writes an sshd hardening drop-in
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(`PermitRootLogin prohibit-password`, `PasswordAuthentication no`) and
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**verifies it took effect** via `sshd -T`; sets the system hostname; installs
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tailscale and joins your tailnet.
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**verifies it took effect** via `sshd -T`; creates a non-root **admin user**;
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optionally **closes root's SSH door** on roles where that is safe; sets the
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system hostname; installs tailscale and joins your tailnet.
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#### The admin user
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rig hardens the SSH door but, until now, never created a human to walk through
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it — every box was administered as `root`, survivable only because of the
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`prohibit-password` drop-in. `bootstrap` now creates a non-root **admin user**
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on **every** role (`control-plane` included, where root's door stays open):
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- In the **`sudo` group, never `docker`** — no supplementary group beyond
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`sudo`. The docker socket is a root API and `docker`-group membership is
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root-equivalent, the same gratuitous path to root `runner install` refuses.
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- **Passwordless (`NOPASSWD`) sudo.** The admin authenticates with an SSH key it
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holds and has no password, so a sudo *password* it does not have would make
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sudo unusable — a non-root user who cannot escalate is not an admin. Key-only
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login + `NOPASSWD` sudo is exactly what Debian/Ubuntu cloud images do for their
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default user. (This is the same `NOPASSWD` the docs warn against for *Coolify's*
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service user — the difference is who holds the account: a human you are
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empowering vs. a non-human identity you are trying to constrain.)
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- **Its `authorized_keys` is seeded once from root's, at creation.** You are
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connected as `root` **right now** using one of root's keys, so copying them
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into the admin account is **live proof the matching private key is in your
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hands** — strictly better than any check rig could invent, and a public key is
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not a secret, so "no credential, ever" does not bend. `--admin-key` composes
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with the seed to add an explicit key.
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> **Seed-once is a deliberate, honest exception to convergence.** Re-seeding on
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> every run would resurrect a key you *deliberately removed* from the admin
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> account. So rig seeds **only at creation** and leaves an existing admin user
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> (and its keys) completely untouched on re-run. Two caveats it handles or names:
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> Coolify writes its **own** key into root's `authorized_keys` when it registers a
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> server, and a blind copy would hand the admin account to Coolify's key — audit
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> the seeded file on Coolify roles. And cloud images can carry `command=`/`from=`
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> forced-command or source restrictions on a key; rig **skips** obviously
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> restricted lines while seeding and warns, rather than let a restriction silently
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> follow to the admin (re-add it with `--admin-key` if it was intended).
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#### The role-aware root door
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"Lock root" sounds like one action. It is **four**, and they do not behave
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alike — measured empirically against a live sshd (OpenSSH 10 / Debian 13), not
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inferred from hardening guides:
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| Technique | Key-based root SSH after | Verdict |
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|---|---|---|
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| `passwd -l root` (shadow → `!*`) | ✅ still works | **harmless** — locking a *password* is not disabling an account; near no-op on cloud images where root already has `*` |
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| `PermitRootLogin prohibit-password` | ✅ works | **safe — what rig does by default** |
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| `usermod --expiredate 1 root` | ❌ PAM denies | **breaks** |
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| root shell → `/usr/sbin/nologin` | ❌ denied | **breaks** (and `chsh` then fails too — recover with `usermod -s /bin/bash root`) |
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| **`PermitRootLogin no`** | ❌ denied | **the only technique `--lock-root` uses** |
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So `--lock-root` means **exactly `PermitRootLogin no`** — never
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`usermod --expiredate` or a nologin shell. Those don't just break interactive
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root; they break **rig's own convergence**, since rig is run as root over SSH and
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a re-run to pick up a fix would find the door bolted from a direction sshd cannot
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reopen. `PermitRootLogin no` leaves the account intact and reopenable by deleting
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one drop-in. (rig's default `PermitRootLogin prohibit-password` already means
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key-only root with **no password surface**, so `passwd -l root` would buy
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approximately nothing on top of it — rig does not bother.)
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Whether root's door *may* close is **per role**, because the constraint is real
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only where something depends on it:
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| Role | Root SSH | `--lock-root` | Why |
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|---|---|---|---|
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| `control-plane` | **must stay** | **refused (exit 2)** | Coolify SSHes to its **own** host (`host.docker.internal`); non-root localhost is unsupported upstream ([coolify#4245](https://github.com/coollabsio/coolify/issues/4245)). A uniform lock-root would cut the control plane off from itself. |
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| `workload` | stays by default | **refused (exit 2)** | Closing it needs Coolify's **experimental** non-root mode — a `coolify` user with `NOPASSWD: ALL` (root by another name) that rig does not provision. Attribution is cheaper via sshd key-fingerprint logging + `auditd`. Revisitable. |
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| `runner` | may close | **allowed** | No Coolify involved. |
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The refusals are **hard errors (exit 2)**, not warnings — the same spirit as
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`runner` refusing `tag:server`. A flag that silently bricks a box's only door is
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worse than no flag. (The `dev` role from #12 does not exist on `main` yet; when
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it lands it joins `runner` as a lockable role.)
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**The lockout problem — verified before the door closes.** Closing root on a box
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whose admin key does not actually work means rescue mode. So before it writes
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`PermitRootLogin no`, rig verifies **locally** that the admin is reachable, and if
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**any** check fails the **door stays open** and rig says which one:
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1. the account exists and is not expired/disabled (an expired account is refused
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by PAM — a *locked password* is fine, key auth is unaffected);
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2. it has a real login shell (not `nologin`/`false`);
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3. `authorized_keys` is non-empty with sane ownership and perms (sshd silently
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ignores a group/world-writable keys file);
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4. `sudo -n true` succeeds under `runuser -u <admin>`;
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5. `sshd -T -C user=<admin>` resolves to something that **permits** the login —
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an `AllowUsers`/`AllowGroups`/`DenyUsers`/`Match` block elsewhere can quietly
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exclude the admin even when the account is perfect.
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What rig **cannot** verify is that you hold the admin's private key — which is
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exactly why it seeds `authorized_keys` from root's (the key you are connected
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with **right now**). The `PermitRootLogin no` drop-in is `00-rig-root.conf`,
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which sorts **before** `00-rig.conf` on purpose (see the first-wins note below),
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installed with the same validate-before-restart + `sshd -t` + rollback + `sshd -T`
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effective-assert dance as the base drop-in. Reopening root later is a deliberate
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manual act: `rm /etc/ssh/sshd_config.d/00-rig-root.conf && systemctl restart ssh`
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— rig will not silently reopen it on a re-run without `--lock-root`.
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**`--hostname` converges both names.** On a box that has already joined,
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`bootstrap` skips `tailscale up` (so a re-run needs no pre-auth key) — but it
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@ -9,13 +9,27 @@ die() { printf 'rig-bootstrap: ERROR: %s\n' "$1" >&2; exit "${2:-1}"; }
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usage() {
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cat <<'EOF'
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usage: rig bootstrap <control-plane|workload|runner> [--hostname <name>] [--ts-tag <tag>]
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usage: rig bootstrap <control-plane|workload|runner> [--hostname <name>]
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[--ts-tag <tag>] [--admin-user <name>] [--admin-key <pubkey>]
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[--lock-root]
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--hostname system + tailnet hostname (default: the role name)
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--ts-tag tailnet tag to advertise (default: tag:server;
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role runner defaults to tag:ci and refuses tag:server —
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a CI box executes repo-controlled code, and your server
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tag's grants must never extend to it)
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--hostname system + tailnet hostname (default: the role name)
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--ts-tag tailnet tag to advertise (default: tag:server;
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role runner defaults to tag:ci and refuses tag:server —
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a CI box executes repo-controlled code, and your server
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tag's grants must never extend to it)
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--admin-user non-root admin account to create on every role (default: admin;
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refuses root). sudo group, key-only, NEVER the docker group.
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Its authorized_keys is seeded ONCE from root's at creation —
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you are connected as root with one of those keys right now, so
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the copy is live proof the private key is in your hands.
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--admin-key an extra public key to add to the admin account at creation,
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composed with the seed above (optional).
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--lock-root close root's SSH door (PermitRootLogin no) once the admin user
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is proven reachable. ROLE-GATED: refused on control-plane
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(Coolify SSHes to its OWN host) and on workload (needs Coolify's
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experimental non-root mode, which rig does not provision);
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allowed on runner.
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Provide the single-use tailscale pre-auth key via the TS_AUTHKEY env var, or
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enter it at the interactive prompt. It is used once and never written to disk.
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@ -37,6 +51,9 @@ if [ "$ROLE" = "runner" ]; then
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else
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TS_TAG="tag:server"
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fi
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ADMIN_USER="admin" # generic default; nothing org-specific ever ships in rig
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ADMIN_KEY=""
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LOCK_ROOT=0
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while [ $# -gt 0 ]; do
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case "$1" in
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--hostname)
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@ -45,6 +62,14 @@ while [ $# -gt 0 ]; do
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--ts-tag)
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[ $# -ge 2 ] || die "--ts-tag needs a value" 2
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TS_TAG="$2"; shift 2 ;;
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--admin-user)
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[ $# -ge 2 ] || die "--admin-user needs a value" 2
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ADMIN_USER="$2"; shift 2 ;;
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--admin-key)
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[ $# -ge 2 ] || die "--admin-key needs a value" 2
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ADMIN_KEY="$2"; shift 2 ;;
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--lock-root)
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LOCK_ROOT=1; shift ;;
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*) die "unknown flag: $1" 2 ;;
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esac
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done
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@ -55,6 +80,28 @@ if [ "$ROLE" = "runner" ] && [ "$TS_TAG" = "tag:server" ]; then
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die "role runner must not advertise tag:server" 2
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fi
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# The admin account is the non-root human door; making it "root" is a
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# contradiction in terms. Refused, not warned — same spirit as runner-install
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# refusing --user root.
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[ "$ADMIN_USER" != "root" ] || die "--admin-user must not be root" 2
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# Role-aware root policy. --lock-root means exactly `PermitRootLogin no` (see the
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# lock-root block far below for why not the other four "lock root" techniques),
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# and on the two Coolify roles that is a self-inflicted fleet outage, so it is
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# REFUSED here (exit 2) rather than warned — a flag that silently bricks a box's
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# only door is worse than no flag. Validated before the root check so the
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# refusal is unit-testable without a live box.
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if [ "$LOCK_ROOT" -eq 1 ]; then
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case "$ROLE" in
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control-plane)
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die "role control-plane must not --lock-root: Coolify reaches its OWN host over SSH (host.docker.internal) and non-root localhost is unsupported upstream (coollabsio/coolify#4245); PermitRootLogin no would cut the control plane off from itself" 2 ;;
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workload)
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die "role workload must not --lock-root: closing root here needs Coolify's experimental non-root mode — a 'coolify' user with NOPASSWD: ALL (root by another name), which rig does not provision. Get attribution cheaper via sshd key-fingerprint logging + auditd. Revisit when Coolify ships granular sudo" 2 ;;
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runner)
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: ;; # no Coolify on a runner; lock-root is allowed once the admin proves reachable
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esac
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fi
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# --- guards ------------------------------------------------------------------
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[ "$(id -u)" -eq 0 ] || die "must run as root"
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if [ -r /etc/os-release ]; then
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@ -85,7 +132,11 @@ apt-get update -qq
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# and the hardening drop-in below targets /etc/ssh/sshd_config.d/ — which
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# only exists once the package is installed. Cloud images ship it; pristine
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# container/VM images (the Incus rehearsal) do not.
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apt-get install -y -qq curl ca-certificates unattended-upgrades openssh-server
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# sudo: the admin user below is placed in the sudo group, which the sudo
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# package creates — and the lock-root verification runs `sudo -n true` under
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# the admin before it will close root's door. A pristine Debian container ships
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# neither the package nor the group; cloud images do.
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apt-get install -y -qq curl ca-certificates unattended-upgrades openssh-server sudo
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# enable periodic unattended upgrades (canonical file; idempotent overwrite)
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cat > /etc/apt/apt.conf.d/20auto-upgrades <<'EOF'
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@ -140,10 +191,246 @@ rm -f "$TMP"
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eff="$(sshd -T 2>/dev/null)" || die "sshd -T failed; refusing to claim a hardened box"
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echo "$eff" | grep -qx 'passwordauthentication no' \
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|| die "sshd still resolves passwordauthentication=yes — a drop-in is beating ${DROPIN}; check ls /etc/ssh/sshd_config.d/"
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echo "$eff" | grep -qxE 'permitrootlogin (prohibit-password|without-password)' \
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# `no` is accepted here too, not just the two prohibit-password spellings: once
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# --lock-root has installed 00-rig-root.conf (below), the effective policy is
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# `no`, which is STRICTLY MORE restrictive (root cannot log in at all, password
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# or key). Refusing it would make the very first re-run of a locked box die in
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# the base-hardening assert — breaking convergence exactly where it matters
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# most. `no` still means "no root password login", so it satisfies the intent.
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echo "$eff" | grep -qxE 'permitrootlogin (prohibit-password|without-password|no)' \
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|| die "sshd still permits root password login — check ls /etc/ssh/sshd_config.d/"
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log "sshd hardening verified (sshd -T: passwordauthentication no)"
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# --- admin user (a non-root human door on every role) ------------------------
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# rig hardens the SSH door but, until now, never created a human to walk through
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# it: every box was administered as root, survivable only because of the
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# prohibit-password drop-in above. The admin is a non-root account in the sudo
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# group with an SSH key — and NEVER the docker group: the docker socket is a
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# root API and docker-group membership is root-equivalent, a gratuitous path to
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# root that runner-install refuses for the same reason. sudo is the ONLY
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# supplementary group it gets. Created on every role (control-plane included,
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# where root must stay) so there is always a human door even where root's stays
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# open.
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ADMIN_HOME="$(getent passwd "$ADMIN_USER" 2>/dev/null | cut -d: -f6)"
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if [ -z "$ADMIN_HOME" ]; then
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log "creating admin user ${ADMIN_USER} (sudo group, no docker)"
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useradd --create-home --shell /bin/bash "$ADMIN_USER"
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usermod -aG sudo "$ADMIN_USER"
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ADMIN_HOME="$(getent passwd "$ADMIN_USER" | cut -d: -f6)"
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# NOPASSWD sudo for the admin — and yes, this is the same NOPASSWD the issue
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# warns against for Coolify's service user. The distinction is who holds the
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# account: the admin is a HUMAN who authenticates with an SSH key they hold
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# and has NO password (useradd leaves the password locked). Requiring a sudo
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# password they do not have would make sudo unusable — a non-root user who
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# cannot escalate is not an admin. Key-only + NOPASSWD sudo is exactly what
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# Debian/Ubuntu cloud images do for their default user. It is wrong for
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# Coolify's user (a non-human identity you are trying to CONSTRAIN, where
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# NOPASSWD hands an attacker who takes the account full root and makes
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# attribution merely cooperative); it is right for a human you are EMPOWERING.
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# visudo -cf validates before install: a malformed sudoers file breaks sudo
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# for everyone, and we are about to (maybe) close root's door behind it.
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SUDOERS_TMP="$(mktemp)"
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printf '%s ALL=(ALL) NOPASSWD:ALL\n' "$ADMIN_USER" > "$SUDOERS_TMP"
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if visudo -cf "$SUDOERS_TMP" >/dev/null 2>&1; then
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install -m 0440 -o root -g root "$SUDOERS_TMP" "/etc/sudoers.d/90-rig-${ADMIN_USER}"
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else
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rm -f "$SUDOERS_TMP"
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die "generated sudoers file for ${ADMIN_USER} failed visudo -c; not installed"
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fi
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rm -f "$SUDOERS_TMP"
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# Seed authorized_keys from ROOT's — ONCE, at creation, and never again.
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# WHY seed from root: the operator is connected as root RIGHT NOW using one
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# of root's keys, so copying them into the admin account is live proof the
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# matching private key is in their hands — strictly better than any check
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# rig could invent, needs no new argument, and a public key is not a secret,
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# so "no credential, ever" does not bend.
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# WHY only once: re-seeding on every run would resurrect a key the operator
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# DELIBERATELY removed from the admin account. Seed-once is therefore, in
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# strict honesty, NOT convergent — an exception named here rather than
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# papered over. An existing admin user (the else branch) is left untouched.
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install -d -m 0700 -o "$ADMIN_USER" -g "$ADMIN_USER" "$ADMIN_HOME/.ssh"
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ADMIN_KEYS="$ADMIN_HOME/.ssh/authorized_keys"
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: > "$ADMIN_KEYS"
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if [ -r /root/.ssh/authorized_keys ]; then
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# Two hazards make a blind copy wrong:
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# - Coolify writes its OWN key into root's authorized_keys when it
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# registers a server. We cannot tell it from the operator's, so we cannot
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# drop it; on control-plane/workload the operator should audit the seeded
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# file (documented in the README).
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# - Cloud images can carry command="…"/from="…" forced-command or source
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# restrictions on a key. Copied verbatim those silently follow to the
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# admin (a from="1.2.3.4" that no longer matches would lock the admin out
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# just as surely). We SKIP any line whose first field is not a bare key
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# type — i.e. one carrying leading options — and warn, rather than seed a
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# key that behaves differently than it reads. Pass it via --admin-key if
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# the restriction is intended.
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while IFS= read -r line; do
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case "$line" in
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""|\#*) continue ;;
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ssh-*|ecdsa-*|sk-ssh-*|sk-ecdsa-*)
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printf '%s\n' "$line" >> "$ADMIN_KEYS" ;;
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*)
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warn "skipping a restricted key line (command=/from=/…) while seeding ${ADMIN_USER} from root; re-add it with --admin-key if intended" ;;
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esac
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done < /root/.ssh/authorized_keys
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fi
|
||||
# --admin-key composes with the seed: an explicit key the operator supplies,
|
||||
# added at creation alongside whatever was copied from root.
|
||||
if [ -n "$ADMIN_KEY" ]; then
|
||||
printf '%s\n' "$ADMIN_KEY" >> "$ADMIN_KEYS"
|
||||
log "added --admin-key to ${ADMIN_USER}"
|
||||
fi
|
||||
chown -R "$ADMIN_USER:$ADMIN_USER" "$ADMIN_HOME/.ssh"
|
||||
chmod 0600 "$ADMIN_KEYS"
|
||||
if [ ! -s "$ADMIN_KEYS" ]; then
|
||||
warn "${ADMIN_USER} has an EMPTY authorized_keys (root had none to seed and no --admin-key given) — it cannot log in yet; add a key before relying on it"
|
||||
fi
|
||||
log "admin user ${ADMIN_USER} created"
|
||||
else
|
||||
# Convergent: an existing admin user is left completely alone — no re-seeding
|
||||
# (see the seed-once note above), no group changes, no sudoers rewrite.
|
||||
log "admin user ${ADMIN_USER} already exists; leaving it and its keys untouched"
|
||||
fi
|
||||
|
||||
# --- lock root's SSH door (--lock-root, role-permitted only) ------------------
|
||||
# Reached only when --lock-root was given AND the role passed the policy gate
|
||||
# above (control-plane/workload already died at exit 2; only runner arrives
|
||||
# here). "Lock root" is FOUR different actions that do NOT behave alike
|
||||
# (measured on OpenSSH 10 / Debian 13):
|
||||
# passwd -l root key-based root SSH still WORKS (near no-op)
|
||||
# PermitRootLogin prohibit key SSH works (what rig does today)
|
||||
# usermod --expiredate 1 BREAKS root SSH via PAM
|
||||
# root shell -> nologin BREAKS (and then chsh fails too)
|
||||
# PermitRootLogin no BREAKS root SSH <-- the ONLY one we want
|
||||
# We want exactly `PermitRootLogin no`. The other break-paths (expiredate,
|
||||
# nologin) would also break rig's OWN convergence: rig is run as root over SSH,
|
||||
# so a re-run to pick up a fix would find the door bolted from a direction sshd
|
||||
# cannot reopen. `PermitRootLogin no` leaves the account intact and reopenable
|
||||
# by deleting one drop-in.
|
||||
if [ "$LOCK_ROOT" -eq 1 ]; then
|
||||
log "verifying ${ADMIN_USER} is reachable before closing root's door"
|
||||
|
||||
# NEVER close root's door in the same breath as opening the admin's without
|
||||
# these checks passing. What rig CANNOT verify is that the operator holds the
|
||||
# admin's private key — which is exactly why we seeded authorized_keys from
|
||||
# root's (the key they are connected with right now). Everything else, we can:
|
||||
fail() { die "refusing --lock-root: $1 (root's door stays OPEN)" 1; }
|
||||
|
||||
# 1. Account exists.
|
||||
id -u "$ADMIN_USER" >/dev/null 2>&1 || fail "admin user ${ADMIN_USER} does not exist"
|
||||
|
||||
# 2. Account not expired/disabled. A locked PASSWORD is fine (key auth is
|
||||
# unaffected — that is the whole lesson of this issue), but an EXPIRED
|
||||
# account (shadow field 8 in the past, i.e. `usermod --expiredate 1`) is
|
||||
# refused by PAM and would block the admin's SSH too. Field 8 empty = never.
|
||||
expire_days="$(getent shadow "$ADMIN_USER" | cut -d: -f8)"
|
||||
if [ -n "$expire_days" ]; then
|
||||
today_days=$(( $(date -u +%s) / 86400 ))
|
||||
[ "$expire_days" -gt "$today_days" ] 2>/dev/null \
|
||||
|| fail "admin account ${ADMIN_USER} is expired/disabled (shadow expire=${expire_days})"
|
||||
fi
|
||||
|
||||
# 3. Valid, real login shell — not nologin/false (which PAM/login refuse).
|
||||
admin_shell="$(getent passwd "$ADMIN_USER" | cut -d: -f7)"
|
||||
case "$admin_shell" in
|
||||
*/nologin|*/false|"") fail "admin ${ADMIN_USER} has no usable login shell (${admin_shell:-none})" ;;
|
||||
esac
|
||||
[ -x "$admin_shell" ] || fail "admin ${ADMIN_USER}'s shell ${admin_shell} is not executable"
|
||||
|
||||
# 4. authorized_keys non-empty, sane ownership + perms. sshd silently ignores
|
||||
# a keys file that is group/world-writable or not owned by the user, so a
|
||||
# present-but-rejected file is as good as no key.
|
||||
akeys="$ADMIN_HOME/.ssh/authorized_keys"
|
||||
[ -s "$akeys" ] || fail "admin ${ADMIN_USER} has an empty/missing authorized_keys (${akeys})"
|
||||
owner="$(stat -c '%U' "$akeys" 2>/dev/null)"
|
||||
[ "$owner" = "$ADMIN_USER" ] || fail "authorized_keys is owned by ${owner:-?}, not ${ADMIN_USER}"
|
||||
perms="$(stat -c '%a' "$akeys" 2>/dev/null)"
|
||||
case "$perms" in
|
||||
600|640|644|400|440) ;; # not group/world writable
|
||||
*) fail "authorized_keys perms ${perms} are too open (sshd would ignore it); want 0600" ;;
|
||||
esac
|
||||
|
||||
# 5. sudo actually works for the admin, non-interactively, as the box will use
|
||||
# it. runuser (not su) mirrors the runner-install precedent.
|
||||
runuser -u "$ADMIN_USER" -- sudo -n true >/dev/null 2>&1 \
|
||||
|| fail "sudo -n true fails for ${ADMIN_USER} (no working passwordless sudo)"
|
||||
|
||||
# 6. sshd's EFFECTIVE resolution for THIS user must permit a key login. An
|
||||
# AllowUsers/AllowGroups/DenyUsers/DenyGroups or Match block elsewhere can
|
||||
# silently exclude the admin even though the account is perfect. We assert
|
||||
# against `sshd -T -C user=<admin>` — the daemon's own resolution — not the
|
||||
# file we wrote, same discipline as the base hardening above. (A Match on
|
||||
# address cannot be resolved without a real connection; that residual gap
|
||||
# is what the second-terminal rehearsal covers.)
|
||||
actx="$(sshd -T -C user="$ADMIN_USER" 2>/dev/null)" \
|
||||
|| fail "sshd -T -C user=${ADMIN_USER} failed to resolve"
|
||||
echo "$actx" | grep -qx 'pubkeyauthentication yes' \
|
||||
|| fail "sshd does not offer publickey auth to ${ADMIN_USER}"
|
||||
admin_groups=" $(id -nG "$ADMIN_USER" 2>/dev/null) "
|
||||
au="$(echo "$actx" | sed -n 's/^allowusers //p')"
|
||||
if [ -n "$au" ]; then
|
||||
printf '%s' " $au " | grep -qF " $ADMIN_USER " \
|
||||
|| fail "sshd AllowUsers excludes ${ADMIN_USER}"
|
||||
fi
|
||||
du="$(echo "$actx" | sed -n 's/^denyusers //p')"
|
||||
if [ -n "$du" ] && printf '%s' " $du " | grep -qF " $ADMIN_USER "; then
|
||||
fail "sshd DenyUsers lists ${ADMIN_USER}"
|
||||
fi
|
||||
ag="$(echo "$actx" | sed -n 's/^allowgroups //p')"
|
||||
if [ -n "$ag" ]; then
|
||||
permitted=0
|
||||
for g in $ag; do
|
||||
case "$admin_groups" in *" $g "*) permitted=1; break ;; esac
|
||||
done
|
||||
[ "$permitted" -eq 1 ] || fail "sshd AllowGroups admits none of ${ADMIN_USER}'s groups"
|
||||
fi
|
||||
dg="$(echo "$actx" | sed -n 's/^denygroups //p')"
|
||||
if [ -n "$dg" ]; then
|
||||
for g in $dg; do
|
||||
case "$admin_groups" in *" $g "*) fail "sshd DenyGroups lists ${ADMIN_USER}'s group ${g}" ;; esac
|
||||
done
|
||||
fi
|
||||
log "admin ${ADMIN_USER} verified reachable (account, shell, keys, sudo, sshd resolution)"
|
||||
|
||||
# Only NOW do we touch root's door — with the exact validate-before-restart +
|
||||
# sshd -t + rollback + sshd -T effective-assert dance the base drop-in uses.
|
||||
# The file sorts BEFORE 00-rig.conf, on purpose: sshd_config is FIRST-wins, so
|
||||
# `PermitRootLogin no` in a 10-* file would be read AFTER 00-rig.conf's
|
||||
# `prohibit-password` and silently discarded — the same first-wins trap that
|
||||
# cost this repo a month of boxes serving passwordauthentication=yes. 00-rig-
|
||||
# root.conf sorts first ('-' < '.'), so it wins over both 00-rig.conf and
|
||||
# cloud-init. (Reopening root is a deliberate manual act: rm this file and
|
||||
# restart ssh — rig does not silently reopen it on a re-run without --lock-root.)
|
||||
ROOT_DROPIN=/etc/ssh/sshd_config.d/00-rig-root.conf
|
||||
RTMP="$(mktemp)"
|
||||
printf 'PermitRootLogin no\n' > "$RTMP"
|
||||
if ! cmp -s "$RTMP" "$ROOT_DROPIN" 2>/dev/null; then
|
||||
RBACK=""
|
||||
[ -e "$ROOT_DROPIN" ] && { RBACK="$(mktemp)"; cp -a "$ROOT_DROPIN" "$RBACK"; }
|
||||
install -m 0644 "$RTMP" "$ROOT_DROPIN"
|
||||
if ! sshd -t 2>/dev/null; then
|
||||
if [ -n "$RBACK" ]; then cp -a "$RBACK" "$ROOT_DROPIN"; else rm -f "$ROOT_DROPIN"; fi
|
||||
rm -f "$RTMP" "$RBACK"
|
||||
die "sshd rejects the merged config with PermitRootLogin no; rolled back, daemon untouched, root's door still OPEN. Run 'sshd -t'."
|
||||
fi
|
||||
rm -f "$RBACK"
|
||||
systemctl restart ssh
|
||||
log "root SSH door closed (PermitRootLogin no drop-in installed)"
|
||||
else
|
||||
log "root SSH door already closed (00-rig-root.conf in place)"
|
||||
fi
|
||||
rm -f "$RTMP"
|
||||
|
||||
# Assert the EFFECTIVE policy, never the file — assert-the-file is what let the
|
||||
# first-wins bug ship green once already.
|
||||
reff="$(sshd -T 2>/dev/null)" || die "sshd -T failed after locking root; investigate before trusting this box" 1
|
||||
echo "$reff" | grep -qx 'permitrootlogin no' \
|
||||
|| die "root door did NOT take effect (sshd -T still permits root login) — a drop-in is beating ${ROOT_DROPIN}; check ls /etc/ssh/sshd_config.d/" 1
|
||||
log "root door verified closed (sshd -T: permitrootlogin no) — from now on re-run rig THROUGH the ${ADMIN_USER} account"
|
||||
fi
|
||||
|
||||
# --- system hostname ----------------------------------------------------------
|
||||
# Set the SYSTEM hostname too, not just the tailnet one. Until 2026-07-12 rig
|
||||
# passed --hostname only to `tailscale up`, so a box reached as `coolify-box`
|
||||
|
|
|
|||
17
test/cli.sh
17
test/cli.sh
|
|
@ -37,9 +37,26 @@ check "bootstrap: unknown role exits 2" 2 "unknown role" "$ROOT/commands/bo
|
|||
check "bootstrap: unknown flag exits 2" 2 "unknown flag" "$ROOT/commands/bootstrap.sh" workload --nope
|
||||
check "bootstrap: hostname needs value" 2 "needs a value" "$ROOT/commands/bootstrap.sh" workload --hostname
|
||||
check "bootstrap: runner refuses tag:server" 2 "must not advertise tag:server" "$ROOT/commands/bootstrap.sh" runner --ts-tag tag:server
|
||||
# --- admin user + role-aware root policy (all validated before the root check) --
|
||||
# Runtime provisioning and the lock-root reachability verification are
|
||||
# rehearsal-only (need a live box); everything the ARG SURFACE decides is here.
|
||||
check "bootstrap: --admin-user refuses root" 2 "must not be root" "$ROOT/commands/bootstrap.sh" workload --admin-user root
|
||||
check "bootstrap: --admin-user needs a value" 2 "needs a value" "$ROOT/commands/bootstrap.sh" workload --admin-user
|
||||
check "bootstrap: --admin-key needs a value" 2 "needs a value" "$ROOT/commands/bootstrap.sh" workload --admin-key
|
||||
# --lock-root is a fleet outage on the two Coolify roles → hard refusal, exit 2.
|
||||
check "bootstrap: --lock-root refused on control-plane" 2 "must not --lock-root" "$ROOT/commands/bootstrap.sh" control-plane --lock-root
|
||||
check "bootstrap: control-plane lock-root names the self-SSH reason" 2 "reaches its OWN host" "$ROOT/commands/bootstrap.sh" control-plane --lock-root
|
||||
check "bootstrap: --lock-root refused on workload" 2 "must not --lock-root" "$ROOT/commands/bootstrap.sh" workload --lock-root
|
||||
check "bootstrap: workload lock-root names non-root mode" 2 "non-root mode" "$ROOT/commands/bootstrap.sh" workload --lock-root
|
||||
if [ "$(id -u)" -ne 0 ]; then
|
||||
check "bootstrap: refuses non-root" 1 "must run as root" env TS_AUTHKEY=x "$ROOT/commands/bootstrap.sh" workload
|
||||
check "bootstrap: runner role parses, refuses non-root" 1 "must run as root" env TS_AUTHKEY=x "$ROOT/commands/bootstrap.sh" runner
|
||||
# --lock-root on runner PARSES the policy gate (runner is permitted) and
|
||||
# falls through to the non-root refusal — proof the gate lets runner past.
|
||||
check "bootstrap: --lock-root on runner parses, refuses non-root" 1 "must run as root" \
|
||||
env TS_AUTHKEY=x "$ROOT/commands/bootstrap.sh" runner --lock-root
|
||||
check "bootstrap: --admin-user parses, refuses non-root" 1 "must run as root" \
|
||||
env TS_AUTHKEY=x "$ROOT/commands/bootstrap.sh" workload --admin-user ops
|
||||
else
|
||||
echo "skip: bootstrap non-root refusals (running as root)"
|
||||
fi
|
||||
|
|
|
|||
Loading…
Reference in a new issue