Files
Varaverk/Plugin/unraid/api/system.php
T
Gmer4Lfe 987313e7dc Document the PHP api layer and fix what documenting it exposed
Writing down what each endpoint actually guarantees made the places it
didn't obvious — shell arguments reaching a crontab or a bash -c
unescaped, master.conf written without tmp+rename, and conf edits that
could be saved without ever being parsed.
2026-08-02 10:11:39 -04:00

99 lines
5.0 KiB
PHP

<?php
// ═══════════════════════════════════════════════════════════════════════════════════════════════
// PURPOSE
// Host power control. Stops the array, shuts the machine down, or reboots it. The three
// most destructive operations the plugin can perform, deliberately isolated in one small
// file rather than folded into a general-purpose action endpoint.
//
// OPERATIONAL MODEL
// The command is detached and the response returns immediately. A shutdown kills the web
// server that is serving this request, so waiting on the child would mean the browser sees
// a connection reset rather than a result. Backgrounding is what lets the UI acknowledge
// the action before the host stops answering.
//
// ok:true therefore means "accepted and dispatched", not "completed". Nothing can report
// the completion of an operation that ends the process reporting it.
//
// DESIGN PRINCIPLES
// Three fixed commands, chosen by name.
// The action string selects among three compiled-in literals through a match. No part
// of the request is ever interpolated into the command, so there is no injection
// surface to protect — the request cannot express a command that is not one of these
// three.
//
// Reads its body as JSON, not as a form.
// php://input is parsed directly, because POST bodies are unreliable on this Unraid
// PHP setup and reading the raw stream sidesteps the form parser entirely.
//
// No scheduling, no delay, no cancel.
// There is nothing to cancel because there is no window in which to cancel it. A delayed
// shutdown with a cancel path would need state, and state that can be wrong about
// whether a host is about to power off is worse than no state.
//
// OPERATIONAL SAFEGUARDS
// POST only, checked first.
// A GET cannot power off the host, so no link, prefetch, bookmark, or browser history
// entry can reach these commands.
//
// Strict allowlist with strict comparison.
// in_array($action, ['stop','shutdown','restart'], true) — the third argument matters.
// Without it PHP's loose comparison would accept values that are not these strings, and
// the match below would then have no arm for them.
//
// The match has no default arm, and that is safe only because of the check above.
// An unmatched action would raise \UnhandledMatchError, which is a hard failure rather
// than a wrong command — but it is unreachable, because the allowlist already rejected
// everything that is not one of the three. The two guards are deliberately redundant.
//
// The audit line is written before the command is dispatched, not after.
// Ordering is the whole point: after a shutdown there is no "after". Timestamp, action
// and originating IP land in actions.log with LOCK_EX while the machine is still
// running, so a power event always has a record of who asked for it.
//
// The audit write is best-effort and never blocks the action.
// @ and FILE_APPEND — a full or read-only flash must not be able to prevent a shutdown.
// Losing the log line is the lesser failure; the log is gitignored and local by design.
//
// REQUEST
// POST {"action":"stop"} stop the array (mdcmd stop)
// POST {"action":"shutdown"} power off the host
// POST {"action":"restart"} reboot the host
//
// RESPONSE
// {"ok":true} accepted and dispatched — not completed
// {"ok":false,"error":"POST only"|"invalid action"}
//
// DEPENDS ON
// include/config.php SCRIPTS_DIR (audit log location)
// /usr/local/sbin/mdcmd array control
// /sbin/shutdown host power control
// ═══════════════════════════════════════════════════════════════════════════════════════════════
header('Content-Type: application/json');
require_once dirname(__DIR__) . '/include/config.php';
if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
echo json_encode(['ok' => false, 'error' => 'POST only']);
exit;
}
$body = json_decode(file_get_contents('php://input'), true) ?? [];
$action = $body['action'] ?? '';
$allowed = ['stop', 'shutdown', 'restart'];
if (!in_array($action, $allowed, true)) {
echo json_encode(['ok' => false, 'error' => 'invalid action']);
exit;
}
$cmd = match($action) {
'stop' => '/usr/local/sbin/mdcmd stop',
'shutdown' => '/sbin/shutdown -h now',
'restart' => '/sbin/shutdown -r now',
};
$logLine = date('Y-m-d H:i:s') . " action={$action} ip=" . ($_SERVER['REMOTE_ADDR'] ?? 'unknown') . "\n";
@file_put_contents(SCRIPTS_DIR . '/actions.log', $logLine, FILE_APPEND | LOCK_EX);
exec($cmd . ' > /dev/null 2>&1 &');
echo json_encode(['ok' => true]);