Files
Varaverk/Plugin/unraid/api/readscript.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

77 lines
3.9 KiB
PHP

<?php
// ═══════════════════════════════════════════════════════════════════════════════════════════════
// PURPOSE
// Script and document reader. Returns the full text of one .sh or .md file inside
// SCRIPTS_DIR — the source view behind the scheduler page's script viewer and the docs tab.
//
// DESIGN PRINCIPLES
// Two extensions, one endpoint.
// Scripts and their READMEs are read the same way because they are read for the same
// reason — someone wants to see what a job actually does. Splitting them would mean two
// endpoints with identical validation.
//
// Returns text, never renders it.
// Markdown arrives as source. Rendering is the browser's job, and doing it here would
// make this endpoint an HTML producer with an HTML producer's escaping problems.
//
// Relative ids only.
// The id is a path relative to SCRIPTS_DIR, so the caller never learns or supplies the
// installation root. That is also what makes the same id valid in internal and appdata
// storage modes.
//
// OPERATIONAL SAFEGUARDS
// Read-only. There is no write counterpart in this file; edits go through movescript.php
// and import_script.php, which have their own validation.
//
// Traversal is blocked before the path is composed.
// str_contains($id, '..') is checked explicitly, and the pattern
// ^[A-Za-z0-9_.\-/]+\.(sh|md)$ excludes null bytes, backslashes, spaces, and every
// shell metacharacter. The slash has to be permitted because ids are Category/name.sh,
// so the '..' check carries the traversal guarantee on its own rather than being
// implied by the character class.
//
// The extension allowlist is the real access boundary.
// Only .sh and .md can be named at all, which is what keeps Configurations/*.conf —
// the files holding every credential in the system — outside this endpoint's reach. Any
// future extension added here has to be checked against that first.
//
// A missing file is reported, not opened.
// file_exists() precedes file_get_contents(), so a bad id returns a named error rather
// than a PHP warning leaking the absolute path into the JSON body.
//
// Known limit: symlinks inside SCRIPTS_DIR are followed.
// Containment is enforced on the id, not on the resolved path, so a symlink placed
// inside the tree pointing outside it would be read. Not tightened with a realpath
// check, because the plugin's own boot model installs SCRIPTS_DIR as a symlink and a
// naive containment test would break it. The tree is git-managed; a rogue symlink in it
// is a repo compromise, which is a larger problem than this endpoint.
//
// REQUEST
// GET ?id=<Category/name.sh|Category/README-name.md>
//
// RESPONSE
// {"ok":true,"content":"<full file text>"}
// {"ok":false,"error":"Invalid id"|"Not found"}
//
// DEPENDS ON
// include/config.php SCRIPTS_DIR
// ═══════════════════════════════════════════════════════════════════════════════════════════════
header('Content-Type: application/json');
require_once dirname(__DIR__) . '/include/config.php';
$id = trim($_GET['id'] ?? '');
// Must be relative path within SCRIPTS_DIR, no traversal, must end in .sh or .md
if (!$id || str_contains($id, '..') || !preg_match('/^[A-Za-z0-9_.\-\/]+\.(sh|md)$/', $id)) {
echo json_encode(['ok' => false, 'error' => 'Invalid id']);
exit;
}
$path = SCRIPTS_DIR . '/' . $id;
if (!file_exists($path)) {
echo json_encode(['ok' => false, 'error' => 'Not found']);
exit;
}
echo json_encode(['ok' => true, 'content' => file_get_contents($path)]);