8494f6a085
Because sandbox is whitelist attribute, attacker will be able to create iframe that has more permission than default. Signed-off-by: RyotaK <49341894+ry0tak@users.noreply.github.com>
79 lines
2.8 KiB
JavaScript
79 lines
2.8 KiB
JavaScript
/* eslint-env browser, jquery */
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// allow some attributes
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var filterXSS = require('xss')
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var whiteListAttr = ['id', 'class', 'style']
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window.whiteListAttr = whiteListAttr
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// allow link starts with '.', '/' and custom protocol with '://', exclude link starts with javascript://
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var linkRegex = /^(?!javascript:\/\/)([\w|-]+:\/\/)|^([.|/])+/i
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// allow data uri, from https://gist.github.com/bgrins/6194623
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var dataUriRegex = /^\s*data:([a-z]+\/[a-z0-9-+.]+(;[a-z-]+=[a-z0-9-]+)?)?(;base64)?,([a-z0-9!$&',()*+;=\-._~:@/?%\s]*)\s*$/i
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// custom white list
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var whiteList = filterXSS.whiteList
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// allow ol specify start number
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whiteList['ol'] = ['start']
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// allow li specify value number
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whiteList['li'] = ['value']
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// allow style tag
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whiteList['style'] = []
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// allow kbd tag
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whiteList['kbd'] = []
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// allow ifram tag with some safe attributes
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whiteList['iframe'] = ['allowfullscreen', 'name', 'referrerpolicy', 'src', 'width', 'height']
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// allow summary tag
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whiteList['summary'] = []
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// allow ruby tag
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whiteList['ruby'] = []
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// allow rp tag for ruby
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whiteList['rp'] = []
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// allow rt tag for ruby
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whiteList['rt'] = []
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// allow figure tag
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whiteList['figure'] = []
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// allow figcaption tag
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whiteList['figcaption'] = []
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var filterXSSOptions = {
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allowCommentTag: true,
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whiteList: whiteList,
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escapeHtml: function (html) {
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// allow html comment in multiple lines
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return html.replace(/<(?!!--)/g, '<').replace(/-->/g, '__HTML_COMMENT_END__').replace(/>/g, '>').replace(/__HTML_COMMENT_END__/g, '-->')
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},
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onIgnoreTag: function (tag, html, options) {
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// allow comment tag
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if (tag === '!--') {
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// do not filter its attributes
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return html.replace(/<(?!!--)/g, '<').replace(/-->/g, '__HTML_COMMENT_END__').replace(/>/g, '>').replace(/__HTML_COMMENT_END__/g, '-->')
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}
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},
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onTagAttr: function (tag, name, value, isWhiteAttr) {
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// allow href and src that match linkRegex
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if (isWhiteAttr && (name === 'href' || name === 'src') && linkRegex.test(value)) {
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return name + '="' + filterXSS.escapeAttrValue(value) + '"'
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}
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// allow data uri in img src
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if (isWhiteAttr && (tag === 'img' && name === 'src') && dataUriRegex.test(value)) {
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return name + '="' + filterXSS.escapeAttrValue(value) + '"'
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}
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},
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onIgnoreTagAttr: function (tag, name, value, isWhiteAttr) {
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// allow attr start with 'data-' or in the whiteListAttr
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if (name.substr(0, 5) === 'data-' || window.whiteListAttr.indexOf(name) !== -1) {
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// escape its value using built-in escapeAttrValue function
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return name + '="' + filterXSS.escapeAttrValue(value) + '"'
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}
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}
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}
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function preventXSS (html) {
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return filterXSS(html, filterXSSOptions)
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}
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window.preventXSS = preventXSS
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module.exports = {
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preventXSS: preventXSS,
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escapeAttrValue: filterXSS.escapeAttrValue
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}
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