Files
clsi/app/js/StaticServerForbidSymlinks.js
2020-02-19 12:14:34 +01:00

72 lines
2.6 KiB
JavaScript

/* eslint-disable
camelcase,
no-cond-assign,
no-unused-vars,
node/no-deprecated-api,
*/
// TODO: This file was created by bulk-decaffeinate.
// Fix any style issues and re-enable lint.
/*
* decaffeinate suggestions:
* DS101: Remove unnecessary use of Array.from
* DS102: Remove unnecessary code created because of implicit returns
* DS103: Rewrite code to no longer use __guard__
* DS207: Consider shorter variations of null checks
* Full docs: https://github.com/decaffeinate/decaffeinate/blob/master/docs/suggestions.md
*/
let ForbidSymlinks;
const Path = require("path");
const fs = require("fs");
const Settings = require("settings-sharelatex");
const logger = require("logger-sharelatex");
const url = require("url");
module.exports = (ForbidSymlinks = function(staticFn, root, options) {
const expressStatic = staticFn(root, options);
const basePath = Path.resolve(root);
return function(req, res, next) {
let file, project_id, result;
const path = __guard__(url.parse(req.url), x => x.pathname);
// check that the path is of the form /project_id_or_name/path/to/file.log
if (result = path.match(/^\/?([a-zA-Z0-9_-]+)\/(.*)/)) {
project_id = result[1];
file = result[2];
} else {
logger.warn({path}, "unrecognized file request");
return res.sendStatus(404);
}
// check that the file does not use a relative path
for (const dir of Array.from(file.split('/'))) {
if (dir === '..') {
logger.warn({path}, "attempt to use a relative path");
return res.sendStatus(404);
}
}
// check that the requested path is normalized
const requestedFsPath = `${basePath}/${project_id}/${file}`;
if (requestedFsPath !== Path.normalize(requestedFsPath)) {
logger.error({path: requestedFsPath}, "requestedFsPath is not normalized");
return res.sendStatus(404);
}
// check that the requested path is not a symlink
return fs.realpath(requestedFsPath, function(err, realFsPath){
if (err != null) {
if (err.code === 'ENOENT') {
return res.sendStatus(404);
} else {
logger.error({err, requestedFsPath, realFsPath, path: req.params[0], project_id: req.params.project_id}, "error checking file access");
return res.sendStatus(500);
}
} else if (requestedFsPath !== realFsPath) {
logger.warn({requestedFsPath, realFsPath, path: req.params[0], project_id: req.params.project_id}, "trying to access a different file (symlink), aborting");
return res.sendStatus(404);
} else {
return expressStatic(req, res, next);
}
});
};
});
function __guard__(value, transform) {
return (typeof value !== 'undefined' && value !== null) ? transform(value) : undefined;
}