Modrinth/helpers/parse.js
Geometrically 4be6b11c1e
Fix data URL filtering (#1111)
* Fix data URL filtering

* upgrade nuxt
2023-04-21 18:39:11 -07:00

128 lines
3.3 KiB
JavaScript

import MarkdownIt from 'markdown-it'
import xss from 'xss'
export const configuredXss = new xss.FilterXSS({
whiteList: {
...xss.whiteList,
summary: [],
h1: ['id'],
h2: ['id'],
h3: ['id'],
h4: ['id'],
h5: ['id'],
h6: ['id'],
kbd: ['id'],
input: ['checked', 'disabled', 'type'],
iframe: ['width', 'height', 'allowfullscreen', 'frameborder', 'start', 'end'],
img: [...xss.whiteList.img, 'style'],
a: [...xss.whiteList.a, 'rel'],
},
css: {
whiteList: {
'image-rendering': /^pixelated$/,
},
},
onIgnoreTagAttr: (tag, name, value) => {
// Allow iframes from acceptable sources
if (tag === 'iframe' && name === 'src') {
const allowedSources = [
{
regex:
/^https?:\/\/(www\.)?youtube(-nocookie)?\.com\/embed\/[a-zA-Z0-9_-]{11}(\?&autoplay=[0-1]{1})?$/,
remove: ['&autoplay=1'], // Prevents autoplay
},
{
regex: /^https?:\/\/(www\.)?discord\.com\/widget\?id=\d{18,19}(&theme=\w+)?$/,
remove: [/&theme=\w+/],
},
]
for (const source of allowedSources) {
if (source.regex.test(value)) {
for (const remove of source.remove) {
value = value.replace(remove, '')
}
return name + '="' + xss.escapeAttrValue(value) + '"'
}
}
}
// For Highlight.JS
if (
name === 'class' &&
['pre', 'code', 'span'].includes(tag) &&
(value.startsWith('hljs-') || value.startsWith('language-'))
) {
return name + '="' + xss.escapeAttrValue(value) + '"'
}
},
safeAttrValue(tag, name, value, _cssFilter) {
if (tag === 'img' && name === 'src' && !value.startsWith('data:')) {
try {
const url = new URL(value)
const allowedHostnames = [
'imgur.com',
'i.imgur.com',
'cdn-raw.modrinth.com',
'cdn.modrinth.com',
'staging-cdn-raw.modrinth.com',
'staging-cdn.modrinth.com',
'github.com',
'raw.githubusercontent.com',
'img.shields.io',
'i.postimg.cc',
'wsrv.nl',
]
if (!allowedHostnames.includes(url.hostname)) {
return `https://wsrv.nl/?url=${encodeURIComponent(value)}`
}
} catch (err) {}
}
return value
},
})
export const md = (options = {}) => {
const md = new MarkdownIt('default', {
html: true,
linkify: true,
breaks: false,
...options,
})
const defaultLinkOpenRenderer =
md.renderer.rules.link_open ||
function (tokens, idx, options, _env, self) {
return self.renderToken(tokens, idx, options)
}
md.renderer.rules.link_open = function (tokens, idx, options, env, self) {
const token = tokens[idx]
const index = token.attrIndex('href')
if (index !== -1) {
const href = token.attrs[index][1]
try {
const url = new URL(href)
const allowedHostnames = ['modrinth.com']
if (allowedHostnames.includes(url.hostname)) {
return defaultLinkOpenRenderer(tokens, idx, options, env, self)
}
} catch (err) {}
}
tokens[idx].attrSet('rel', 'noopener nofollow ugc')
return defaultLinkOpenRenderer(tokens, idx, options, env, self)
}
return md
}
export const renderString = (string) => configuredXss.process(md().render(string))