CasperSecurity
/*!
* send
* Copyright(c) 2012 TJ Holowaychuk
* Copyright(c) 2014-2016 Douglas Christopher Wilson
* MIT Licensed
*/
'use strict'
/**
* Module dependencies.
* @private
*/
var createError = require('http-errors')
var debug = require('debug')('send')
var deprecate = require('depd')('send')
var destroy = require('destroy')
var encodeUrl = require('encodeurl')
var escapeHtml = require('escape-html')
var etag = require('etag')
var fresh = require('fresh')
var fs = require('fs')
var mime = require('mime')
var ms = require('ms')
var onFinished = require('on-finished')
var parseRange = require('range-parser')
var path = require('path')
var statuses = require('statuses')
var Stream = require('stream')
var util = require('util')
/**
* Path function references.
* @private
*/
var extname = path.extname
var join = path.join
var normalize = path.normalize
var resolve = path.resolve
var sep = path.sep
/**
* Regular expression for identifying a bytes Range header.
* @private
*/
var BYTES_RANGE_REGEXP = /^ *bytes=/
/**
* Maximum value allowed for the max age.
* @private
*/
var MAX_MAXAGE = 60 * 60 * 24 * 365 * 1000 // 1 year
/**
* Regular expression to match a path with a directory up component.
* @private
*/
var UP_PATH_REGEXP = /(?:^|[\\/])\.\.(?:[\\/]|$)/
/**
* Module exports.
* @public
*/
module.exports = send
module.exports.mime = mime
/**
* Return a `SendStream` for `req` and `path`.
*
* @param {object} req
* @param {string} path
* @param {object} [options]
* @return {SendStream}
* @public
*/
function send (req, path, options) {
return new SendStream(req, path, options)
}
/**
* Initialize a `SendStream` with the given `path`.
*
* @param {Request} req
* @param {String} path
* @param {object} [options]
* @private
*/
function SendStream (req, path, options) {
Stream.call(this)
var opts = options || {}
this.options = opts
this.path = path
this.req = req
this._acceptRanges = opts.acceptRanges !== undefined
? Boolean(opts.acceptRanges)
: true
this._cacheControl = opts.cacheControl !== undefined
? Boolean(opts.cacheControl)
: true
this._etag = opts.etag !== undefined
? Boolean(opts.etag)
: true
this._dotfiles = opts.dotfiles !== undefined
? opts.dotfiles
: 'ignore'
if (this._dotfiles !== 'ignore' && this._dotfiles !== 'allow' && this._dotfiles !== 'deny') {
throw new TypeError('dotfiles option must be "allow", "deny", or "ignore"')
}
this._hidden = Boolean(opts.hidden)
if (opts.hidden !== undefined) {
deprecate('hidden: use dotfiles: \'' + (this._hidden ? 'allow' : 'ignore') + '\' instead')
}
// legacy support
if (opts.dotfiles === undefined) {
this._dotfiles = undefined
}
this._extensions = opts.extensions !== undefined
? normalizeList(opts.extensions, 'extensions option')
: []
this._immutable = opts.immutable !== undefined
? Boolean(opts.immutable)
: false
this._index = opts.index !== undefined
? normalizeList(opts.index, 'index option')
: ['index.html']
this._lastModified = opts.lastModified !== undefined
? Boolean(opts.lastModified)
: true
this._maxage = opts.maxAge || opts.maxage
this._maxage = typeof this._maxage === 'string'
? ms(this._maxage)
: Number(this._maxage)
this._maxage = !isNaN(this._maxage)
? Math.min(Math.max(0, this._maxage), MAX_MAXAGE)
: 0
this._root = opts.root
? resolve(opts.root)
: null
if (!this._root && opts.from) {
this.from(opts.from)
}
}
/**
* Inherits from `Stream`.
*/
util.inherits(SendStream, Stream)
/**
* Enable or disable etag generation.
*
* @param {Boolean} val
* @return {SendStream}
* @api public
*/
SendStream.prototype.etag = deprecate.function(function etag (val) {
this._etag = Boolean(val)
debug('etag %s', this._etag)
return this
}, 'send.etag: pass etag as option')
/**
* Enable or disable "hidden" (dot) files.
*
* @param {Boolean} path
* @return {SendStream}
* @api public
*/
SendStream.prototype.hidden = deprecate.function(function hidden (val) {
this._hidden = Boolean(val)
this._dotfiles = undefined
debug('hidden %s', this._hidden)
return this
}, 'send.hidden: use dotfiles option')
/**
* Set index `paths`, set to a falsy
* value to disable index support.
*
* @param {String|Boolean|Array} paths
* @return {SendStream}
* @api public
*/
SendStream.prototype.index = deprecate.function(function index (paths) {
var index = !paths ? [] : normalizeList(paths, 'paths argument')
debug('index %o', paths)
this._index = index
return this
}, 'send.index: pass index as option')
/**
* Set root `path`.
*
* @param {String} path
* @return {SendStream}
* @api public
*/
SendStream.prototype.root = function root (path) {
this._root = resolve(String(path))
debug('root %s', this._root)
return this
}
SendStream.prototype.from = deprecate.function(SendStream.prototype.root,
'send.from: pass root as option')
SendStream.prototype.root = deprecate.function(SendStream.prototype.root,
'send.root: pass root as option')
/**
* Set max-age to `maxAge`.
*
* @param {Number} maxAge
* @return {SendStream}
* @api public
*/
SendStream.prototype.maxage = deprecate.function(function maxage (maxAge) {
this._maxage = typeof maxAge === 'string'
? ms(maxAge)
: Number(maxAge)
this._maxage = !isNaN(this._maxage)
? Math.min(Math.max(0, this._maxage), MAX_MAXAGE)
: 0
debug('max-age %d', this._maxage)
return this
}, 'send.maxage: pass maxAge as option')
/**
* Emit error with `status`.
*
* @param {number} status
* @param {Error} [err]
* @private
*/
SendStream.prototype.error = function error (status, err) {
// emit if listeners instead of responding
if (hasListeners(this, 'error')) {
return this.emit('error', createError(status, err, {
expose: false
}))
}
var res = this.res
var msg = statuses[status] || String(status)
var doc = createHtmlDocument('Error', escapeHtml(msg))
// clear existing headers
clearHeaders(res)
// add error headers
if (err && err.headers) {
setHeaders(res, err.headers)
}
// send basic response
res.statusCode = status
res.setHeader('Content-Type', 'text/html; charset=UTF-8')
res.setHeader('Content-Length', Buffer.byteLength(doc))
res.setHeader('Content-Security-Policy', "default-src 'none'")
res.setHeader('X-Content-Type-Options', 'nosniff')
res.end(doc)
}
/**
* Check if the pathname ends with "/".
*
* @return {boolean}
* @private
*/
SendStream.prototype.hasTrailingSlash = function hasTrailingSlash () {
return this.path[this.path.length - 1] === '/'
}
/**
* Check if this is a conditional GET request.
*
* @return {Boolean}
* @api private
*/
SendStream.prototype.isConditionalGET = function isConditionalGET () {
return this.req.headers['if-match'] ||
this.req.headers['if-unmodified-since'] ||
this.req.headers['if-none-match'] ||
this.req.headers['if-modified-since']
}
/**
* Check if the request preconditions failed.
*
* @return {boolean}
* @private
*/
SendStream.prototype.isPreconditionFailure = function isPreconditionFailure () {
var req = this.req
var res = this.res
// if-match
var match = req.headers['if-match']
if (match) {
var etag = res.getHeader('ETag')
return !etag || (match !== '*' && parseTokenList(match).every(function (match) {
return match !== etag && match !== 'W/' + etag && 'W/' + match !== etag
}))
}
// if-unmodified-since
var unmodifiedSince = parseHttpDate(req.headers['if-unmodified-since'])
if (!isNaN(unmodifiedSince)) {
var lastModified = parseHttpDate(res.getHeader('Last-Modified'))
return isNaN(lastModified) || lastModified > unmodifiedSince
}
return false
}
/**
* Strip content-* header fields.
*
* @private
*/
SendStream.prototype.removeContentHeaderFields = function removeContentHeaderFields () {
var res = this.res
var headers = getHeaderNames(res)
for (var i = 0; i < headers.length; i++) {
var header = headers[i]
if (header.substr(0, 8) === 'content-' && header !== 'content-location') {
res.removeHeader(header)
}
}
}
/**
* Respond with 304 not modified.
*
* @api private
*/
SendStream.prototype.notModified = function notModified () {
var res = this.res
debug('not modified')
this.removeContentHeaderFields()
res.statusCode = 304
res.end()
}
/**
* Raise error that headers already sent.
*
* @api private
*/
SendStream.prototype.headersAlreadySent = function headersAlreadySent () {
var err = new Error('Can\'t set headers after they are sent.')
debug('headers already sent')
this.error(500, err)
}
/**
* Check if the request is cacheable, aka
* responded with 2xx or 304 (see RFC 2616 section 14.2{5,6}).
*
* @return {Boolean}
* @api private
*/
SendStream.prototype.isCachable = function isCachable () {
var statusCode = this.res.statusCode
return (statusCode >= 200 && statusCode < 300) ||
statusCode === 304
}
/**
* Handle stat() error.
*
* @param {Error} error
* @private
*/
SendStream.prototype.onStatError = function onStatError (error) {
switch (error.code) {
case 'ENAMETOOLONG':
case 'ENOENT':
case 'ENOTDIR':
this.error(404, error)
break
default:
this.error(500, error)
break
}
}
/**
* Check if the cache is fresh.
*
* @return {Boolean}
* @api private
*/
SendStream.prototype.isFresh = function isFresh () {
return fresh(this.req.headers, {
etag: this.res.getHeader('ETag'),
'last-modified': this.res.getHeader('Last-Modified')
})
}
/**
* Check if the range is fresh.
*
* @return {Boolean}
* @api private
*/
SendStream.prototype.isRangeFresh = function isRangeFresh () {
var ifRange = this.req.headers['if-range']
if (!ifRange) {
return true
}
// if-range as etag
if (ifRange.indexOf('"') !== -1) {
var etag = this.res.getHeader('ETag')
return Boolean(etag && ifRange.indexOf(etag) !== -1)
}
// if-range as modified date
var lastModified = this.res.getHeader('Last-Modified')
return parseHttpDate(lastModified) <= parseHttpDate(ifRange)
}
/**
* Redirect to path.
*
* @param {string} path
* @private
*/
SendStream.prototype.redirect = function redirect (path) {
var res = this.res
if (hasListeners(this, 'directory')) {
this.emit('directory', res, path)
return
}
if (this.hasTrailingSlash()) {
this.error(403)
return
}
var loc = encodeUrl(collapseLeadingSlashes(this.path + '/'))
var doc = createHtmlDocument('Redirecting', 'Redirecting to <a href="' + escapeHtml(loc) + '">' +
escapeHtml(loc) + '</a>')
// redirect
res.statusCode = 301
res.setHeader('Content-Type', 'text/html; charset=UTF-8')
res.setHeader('Content-Length', Buffer.byteLength(doc))
res.setHeader('Content-Security-Policy', "default-src 'none'")
res.setHeader('X-Content-Type-Options', 'nosniff')
res.setHeader('Location', loc)
res.end(doc)
}
/**
* Pipe to `res.
*
* @param {Stream} res
* @return {Stream} res
* @api public
*/
SendStream.prototype.pipe = function pipe (res) {
// root path
var root = this._root
// references
this.res = res
// decode the path
var path = decode(this.path)
if (path === -1) {
this.error(400)
return res
}
// null byte(s)
if (~path.indexOf('\0')) {
this.error(400)
return res
}
var parts
if (root !== null) {
// normalize
if (path) {
path = normalize('.' + sep + path)
}
// malicious path
if (UP_PATH_REGEXP.test(path)) {
debug('malicious path "%s"', path)
this.error(403)
return res
}
// explode path parts
parts = path.split(sep)
// join / normalize from optional root dir
path = normalize(join(root, path))
} else {
// ".." is malicious without "root"
if (UP_PATH_REGEXP.test(path)) {
debug('malicious path "%s"', path)
this.error(403)
return res
}
// explode path parts
parts = normalize(path).split(sep)
// resolve the path
path = resolve(path)
}
// dotfile handling
if (containsDotFile(parts)) {
var access = this._dotfiles
// legacy support
if (access === undefined) {
access = parts[parts.length - 1][0] === '.'
? (this._hidden ? 'allow' : 'ignore')
: 'allow'
}
debug('%s dotfile "%s"', access, path)
switch (access) {
case 'allow':
break
case 'deny':
this.error(403)
return res
case 'ignore':
default:
this.error(404)
return res
}
}
// index file support
if (this._index.length && this.hasTrailingSlash()) {
this.sendIndex(path)
return res
}
this.sendFile(path)
return res
}
/**
* Transfer `path`.
*
* @param {String} path
* @api public
*/
SendStream.prototype.send = function send (path, stat) {
var len = stat.size
var options = this.options
var opts = {}
var res = this.res
var req = this.req
var ranges = req.headers.range
var offset = options.start || 0
if (headersSent(res)) {
// impossible to send now
this.headersAlreadySent()
return
}
debug('pipe "%s"', path)
// set header fields
this.setHeader(path, stat)
// set content-type
this.type(path)
// conditional GET support
if (this.isConditionalGET()) {
if (this.isPreconditionFailure()) {
this.error(412)
return
}
if (this.isCachable() && this.isFresh()) {
this.notModified()
return
}
}
// adjust len to start/end options
len = Math.max(0, len - offset)
if (options.end !== undefined) {
var bytes = options.end - offset + 1
if (len > bytes) len = bytes
}
// Range support
if (this._acceptRanges && BYTES_RANGE_REGEXP.test(ranges)) {
// parse
ranges = parseRange(len, ranges, {
combine: true
})
// If-Range support
if (!this.isRangeFresh()) {
debug('range stale')
ranges = -2
}
// unsatisfiable
if (ranges === -1) {
debug('range unsatisfiable')
// Content-Range
res.setHeader('Content-Range', contentRange('bytes', len))
// 416 Requested Range Not Satisfiable
return this.error(416, {
headers: { 'Content-Range': res.getHeader('Content-Range') }
})
}
// valid (syntactically invalid/multiple ranges are treated as a regular response)
if (ranges !== -2 && ranges.length === 1) {
debug('range %j', ranges)
// Content-Range
res.statusCode = 206
res.setHeader('Content-Range', contentRange('bytes', len, ranges[0]))
// adjust for requested range
offset += ranges[0].start
len = ranges[0].end - ranges[0].start + 1
}
}
// clone options
for (var prop in options) {
opts[prop] = options[prop]
}
// set read options
opts.start = offset
opts.end = Math.max(offset, offset + len - 1)
// content-length
res.setHeader('Content-Length', len)
// HEAD support
if (req.method === 'HEAD') {
res.end()
return
}
this.stream(path, opts)
}
/**
* Transfer file for `path`.
*
* @param {String} path
* @api private
*/
SendStream.prototype.sendFile = function sendFile (path) {
var i = 0
var self = this
debug('stat "%s"', path)
fs.stat(path, function onstat (err, stat) {
if (err && err.code === 'ENOENT' && !extname(path) && path[path.length - 1] !== sep) {
// not found, check extensions
return next(err)
}
if (err) return self.onStatError(err)
if (stat.isDirectory()) return self.redirect(path)
self.emit('file', path, stat)
self.send(path, stat)
})
function next (err) {
if (self._extensions.length <= i) {
return err
? self.onStatError(err)
: self.error(404)
}
var p = path + '.' + self._extensions[i++]
debug('stat "%s"', p)
fs.stat(p, function (err, stat) {
if (err) return next(err)
if (stat.isDirectory()) return next()
self.emit('file', p, stat)
self.send(p, stat)
})
}
}
/**
* Transfer index for `path`.
*
* @param {String} path
* @api private
*/
SendStream.prototype.sendIndex = function sendIndex (path) {
var i = -1
var self = this
function next (err) {
if (++i >= self._index.length) {
if (err) return self.onStatError(err)
return self.error(404)
}
var p = join(path, self._index[i])
debug('stat "%s"', p)
fs.stat(p, function (err, stat) {
if (err) return next(err)
if (stat.isDirectory()) return next()
self.emit('file', p, stat)
self.send(p, stat)
})
}
next()
}
/**
* Stream `path` to the response.
*
* @param {String} path
* @param {Object} options
* @api private
*/
SendStream.prototype.stream = function stream (path, options) {
// TODO: this is all lame, refactor meeee
var finished = false
var self = this
var res = this.res
// pipe
var stream = fs.createReadStream(path, options)
this.emit('stream', stream)
stream.pipe(res)
// response finished, done with the fd
onFinished(res, function onfinished () {
finished = true
destroy(stream)
})
// error handling code-smell
stream.on('error', function onerror (err) {
// request already finished
if (finished) return
// clean up stream
finished = true
destroy(stream)
// error
self.onStatError(err)
})
// end
stream.on('end', function onend () {
self.emit('end')
})
}
/**
* Set content-type based on `path`
* if it hasn't been explicitly set.
*
* @param {String} path
* @api private
*/
SendStream.prototype.type = function type (path) {
var res = this.res
if (res.getHeader('Content-Type')) return
var type = mime.lookup(path)
if (!type) {
debug('no content-type')
return
}
var charset = mime.charsets.lookup(type)
debug('content-type %s', type)
res.setHeader('Content-Type', type + (charset ? '; charset=' + charset : ''))
}
/**
* Set response header fields, most
* fields may be pre-defined.
*
* @param {String} path
* @param {Object} stat
* @api private
*/
SendStream.prototype.setHeader = function setHeader (path, stat) {
var res = this.res
this.emit('headers', res, path, stat)
if (this._acceptRanges && !res.getHeader('Accept-Ranges')) {
debug('accept ranges')
res.setHeader('Accept-Ranges', 'bytes')
}
if (this._cacheControl && !res.getHeader('Cache-Control')) {
var cacheControl = 'public, max-age=' + Math.floor(this._maxage / 1000)
if (this._immutable) {
cacheControl += ', immutable'
}
debug('cache-control %s', cacheControl)
res.setHeader('Cache-Control', cacheControl)
}
if (this._lastModified && !res.getHeader('Last-Modified')) {
var modified = stat.mtime.toUTCString()
debug('modified %s', modified)
res.setHeader('Last-Modified', modified)
}
if (this._etag && !res.getHeader('ETag')) {
var val = etag(stat)
debug('etag %s', val)
res.setHeader('ETag', val)
}
}
/**
* Clear all headers from a response.
*
* @param {object} res
* @private
*/
function clearHeaders (res) {
var headers = getHeaderNames(res)
for (var i = 0; i < headers.length; i++) {
res.removeHeader(headers[i])
}
}
/**
* Collapse all leading slashes into a single slash
*
* @param {string} str
* @private
*/
function collapseLeadingSlashes (str) {
for (var i = 0; i < str.length; i++) {
if (str[i] !== '/') {
break
}
}
return i > 1
? '/' + str.substr(i)
: str
}
/**
* Determine if path parts contain a dotfile.
*
* @api private
*/
function containsDotFile (parts) {
for (var i = 0; i < parts.length; i++) {
var part = parts[i]
if (part.length > 1 && part[0] === '.') {
return true
}
}
return false
}
/**
* Create a Content-Range header.
*
* @param {string} type
* @param {number} size
* @param {array} [range]
*/
function contentRange (type, size, range) {
return type + ' ' + (range ? range.start + '-' + range.end : '*') + '/' + size
}
/**
* Create a minimal HTML document.
*
* @param {string} title
* @param {string} body
* @private
*/
function createHtmlDocument (title, body) {
return '<!DOCTYPE html>\n' +
'<html lang="en">\n' +
'<head>\n' +
'<meta charset="utf-8">\n' +
'<title>' + title + '</title>\n' +
'</head>\n' +
'<body>\n' +
'<pre>' + body + '</pre>\n' +
'</body>\n' +
'</html>\n'
}
/**
* decodeURIComponent.
*
* Allows V8 to only deoptimize this fn instead of all
* of send().
*
* @param {String} path
* @api private
*/
function decode (path) {
try {
return decodeURIComponent(path)
} catch (err) {
return -1
}
}
/**
* Get the header names on a respnse.
*
* @param {object} res
* @returns {array[string]}
* @private
*/
function getHeaderNames (res) {
return typeof res.getHeaderNames !== 'function'
? Object.keys(res._headers || {})
: res.getHeaderNames()
}
/**
* Determine if emitter has listeners of a given type.
*
* The way to do this check is done three different ways in Node.js >= 0.8
* so this consolidates them into a minimal set using instance methods.
*
* @param {EventEmitter} emitter
* @param {string} type
* @returns {boolean}
* @private
*/
function hasListeners (emitter, type) {
var count = typeof emitter.listenerCount !== 'function'
? emitter.listeners(type).length
: emitter.listenerCount(type)
return count > 0
}
/**
* Determine if the response headers have been sent.
*
* @param {object} res
* @returns {boolean}
* @private
*/
function headersSent (res) {
return typeof res.headersSent !== 'boolean'
? Boolean(res._header)
: res.headersSent
}
/**
* Normalize the index option into an array.
*
* @param {boolean|string|array} val
* @param {string} name
* @private
*/
function normalizeList (val, name) {
var list = [].concat(val || [])
for (var i = 0; i < list.length; i++) {
if (typeof list[i] !== 'string') {
throw new TypeError(name + ' must be array of strings or false')
}
}
return list
}
/**
* Parse an HTTP Date into a number.
*
* @param {string} date
* @private
*/
function parseHttpDate (date) {
var timestamp = date && Date.parse(date)
return typeof timestamp === 'number'
? timestamp
: NaN
}
/**
* Parse a HTTP token list.
*
* @param {string} str
* @private
*/
function parseTokenList (str) {
var end = 0
var list = []
var start = 0
// gather tokens
for (var i = 0, len = str.length; i < len; i++) {
switch (str.charCodeAt(i)) {
case 0x20: /* */
if (start === end) {
start = end = i + 1
}
break
case 0x2c: /* , */
if (start !== end) {
list.push(str.substring(start, end))
}
start = end = i + 1
break
default:
end = i + 1
break
}
}
// final token
if (start !== end) {
list.push(str.substring(start, end))
}
return list
}
/**
* Set an object of headers on a response.
*
* @param {object} res
* @param {object} headers
* @private
*/
function setHeaders (res, headers) {
var keys = Object.keys(headers)
for (var i = 0; i < keys.length; i++) {
var key = keys[i]
res.setHeader(key, headers[key])
}
}