rig/commands/lib/users-config.sh
Claude 2dc396d557 feat(users): close-root — shut the human-class root door once an admin key works
class decides root SSH's fate, and this is human's: install
/etc/ssh/sshd_config.d/00-rig-users.conf (PermitRootLogin no), where the NAME
is the mechanism — sshd_config is first-wins, the Include glob expands
lexically, and '-' sorts before '.', so it is read before bootstrap's
00-rig.conf and wins. Gated three ways, no --force: a marker must exist
(never shut the root door blind), it must say class=human (on a server root
is the control plane's automation identity — closing it severs fleet
management), and some rig-admin member must already hold a non-empty
authorized_keys (never close the only door). The gate's policy lives in the
lib as assert_marker_human so the harness proves every refusal against
fixture markers as non-root; RIG_ROLE_MARKER keeps the command pointable at
the same fixtures. Apply is bootstrap's validate-then-apply shape verbatim —
cmp-guard, sshd -t on the merged config before the restart with rollback,
then the sshd -T effective assertion. Bootstrap's own permitrootlogin
assertion widens to accept 'no': the closed door is strictly harder, never
broken, and by first-wins bootstrap cannot reopen it.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-07-17 19:28:25 +00:00

114 lines
4.7 KiB
Bash

#!/usr/bin/env bash
# Shared parsing for the rig users family. Sourced by the users-* commands and
# by the test harness against fixture files; never executed on its own.
# The users file is line-based and whitespace-separated on purpose: a
# rig-bootstrapped box has no YAML parser and no jq, and `read` parses this
# shape for free — same jq-free reason runner-config.sh greps JSON. One line
# per key:
#
# # user roles ssh public key
# dan admin,box ssh-ed25519 AAAA... dan@laptop
#
# Repeated username lines are additional authorized keys; the roles field must
# be IDENTICAL on each — a repeated line means "another key", never a quiet
# role edit hiding mid-file. '#' comments and blank lines are skipped.
# parse_users_file <path>
#
# Emits one normalized 'user|roles|key' line per key line on stdout. On ANY
# validation error: EVERY error goes to stderr, each with its line number, no
# stdout, return 1. All errors in one pass because a bad file should cost one
# fix cycle, not one round-trip per line.
#
# Refusals: unknown role (the valid set is named), differing roles across one
# user's lines, root as username (root's keys are class policy's business, not
# this file's), malformed line (fewer than 3 fields, or a key field that does
# not start with an SSH key type), duplicate identical key line.
parse_users_file() {
local path="$1"
local -a errs=() out=() rlist=()
local -A first_roles=() seen=()
local line u r k role ok n=0
while IFS= read -r line || [ -n "$line" ]; do
n=$((n + 1))
if [[ "$line" =~ ^[[:space:]]*(#|$) ]]; then continue; fi
read -r u r k <<< "$line"
if [ -z "${k:-}" ]; then
errs+=("line $n: malformed — expected 'user roles ssh-public-key' (3+ whitespace-separated fields)")
continue
fi
case "$k" in
ssh-*|ecdsa-*|sk-ssh-*|sk-ecdsa-*) ;;
*)
errs+=("line $n: malformed — key field must start with an SSH key type (ssh-..., ecdsa-...)")
continue ;;
esac
if [ "$u" = "root" ]; then
errs+=("line $n: 'root' is not a rig-managed user — this file names operators; root SSH's fate is class policy")
continue
fi
ok=1
IFS=',' read -ra rlist <<< "$r"
for role in "${rlist[@]}"; do
case "$role" in
admin|rig|box) ;;
*) errs+=("line $n: unknown role '$role' for $u (valid roles: admin rig box)"); ok=0 ;;
esac
done
if [ -n "${first_roles[$u]:-}" ] && [ "${first_roles[$u]}" != "$r" ]; then
errs+=("line $n: $u has roles '$r' here but '${first_roles[$u]}' earlier — repeated lines add keys, roles must be identical")
ok=0
fi
if [ -z "${first_roles[$u]:-}" ]; then first_roles[$u]="$r"; fi
if [ -n "${seen[$u|$k]:-}" ]; then
errs+=("line $n: duplicate key line for $u (same key already on line ${seen[$u|$k]})")
continue
fi
seen[$u|$k]="$n"
if [ "$ok" -eq 1 ]; then out+=("$u|$r|$k"); fi
done < "$path"
if [ "${#errs[@]}" -gt 0 ]; then
printf '%s\n' "${errs[@]}" >&2
return 1
fi
if [ "${#out[@]}" -gt 0 ]; then printf '%s\n' "${out[@]}"; fi
return 0
}
# read_role_marker <path> — the marker line bootstrap wrote
# (`role=... class=... host=... join=...`), or nothing when absent. NO policy
# here: what an absent marker or a given class MEANS is each caller's call
# (apply notes it, close-root refuses on it) — this reader only reads.
read_role_marker() {
[ -r "$1" ] || return 0
head -n1 "$1"
}
# assert_marker_human <marker_path> — close-root's marker gate: return 0,
# silently, only when the marker says class=human; otherwise print the refusal
# reason on stdout and return 1 (the caller wraps it in its own die). The
# policy is a pure lib function on purpose: the CLI path sits behind the root
# check, so the harness proves every refusal HERE, against fixture markers,
# non-root (repo precedent: parse_users_file, assert_runner_repo).
assert_marker_human() {
local marker
marker="$(read_role_marker "$1")"
if [ -z "$marker" ]; then
# No marker means rig cannot know whether root here is a human's bad habit
# or the control plane's automation door — refuse to shut it blind.
printf '%s\n' "no /etc/rig/role marker: re-run rig bootstrap so this box knows what it is; refusing to shut the root door blind"
return 1
fi
case "$marker" in
*class=human*) return 0 ;;
*class=server*)
# Root SSH on a server IS the control plane's (Coolify's) automation
# identity — closing it severs fleet management. No --force exists.
printf '%s\n' "class=server: root here is the control plane's automation identity — closing it severs fleet management"
return 1 ;;
*)
printf '%s\n' "marker names no class (${marker}): re-run rig bootstrap; refusing to shut the root door blind"
return 1 ;;
esac
}