Page MenuHome

02_markdown-sanitizer.js
No OneTemporary

File Metadata

Created
Thu, Jan 23, 10:05 AM

02_markdown-sanitizer.js

(function () {
var output, Converter;
if (typeof exports === "object" && typeof require === "function") { // we're in a CommonJS (e.g. Node.js) module
output = exports;
Converter = require("./Markdown.Converter").Converter;
} else {
output = window.Markdown;
Converter = output.Converter;
}
output.getSanitizingConverter = function () {
var converter = new Converter();
converter.hooks.chain("postConversion", sanitizeHtml);
converter.hooks.chain("postConversion", balanceTags);
return converter;
}
function sanitizeHtml(html) {
return html.replace(/<[^>]*>?/gi, sanitizeTag);
}
// (tags that can be opened/closed) | (tags that stand alone)
var basic_tag_whitelist = /^(<\/?(b|blockquote|code|del|dd|dl|dt|em|h1|h2|h3|i|iframe|kbd|li|ol(?: start="\d+")?|p|pre|s|sup|sub|strong|strike|ul|video)>|<(br|hr)\s?\/?>)$/i;
// <a href="url..." optional title>|</a>
var a_white = /^(<a\shref="((https?|ftp):\/\/|\/)[-A-Za-z0-9+&@#\/%?=~_|!:,.;\(\)*[\]$]+"(\stitle="[^"<>]+")?(\sclass="[^"<>]+")?\s?>|<\/a>)$/i;
// Cloud custom: Allow iframe embed from YouTube, Vimeo and SoundCloud
var iframe_youtube = /^(<iframe(\swidth="\d{1,3}")?(\sheight="\d{1,3}")\ssrc="((https?):\/\/|\/)[-A-Za-z0-9+&@#\/%?=~_|!:,.;\(\)*[\]$]+"(\sframeborder="\d{1,3}")?(\sallowfullscreen)\s?>|<\/iframe>)$/i;
var iframe_vimeo = /^(<iframe(\ssrc="((https?):\/\/|\/)[-A-Za-z0-9+&@#\/%?=~_|!:,.;\(\)*[\]$]+"?\swidth="\d{1,3}")?(\sheight="\d{1,3}")?(\sframeborder="\d{1,3}")?(\swebkitallowfullscreen)\s?(\smozallowfullscreen)\s?(\sallowfullscreen)\s?>|<\/iframe>)$/i;
var iframe_soundcloud = /^(<iframe(\swidth="\d{1,3}\%")?(\sheight="\d{1,3}")?(\sscrolling="(?:yes|no)")?(\sframeborder="(?:yes|no)")\ssrc="((https?):\/\/|\/)[-A-Za-z0-9+&@#\/%?=~_|!:,.;\(\)*[\]$]+"\s?>|<\/iframe>)$/i;
var iframe_googlestorage = /^(<iframe\ssrc="https:\/\/storage.googleapis.com\/institute-storage\/.+"\sstyle=".*"\s?>|<\/iframe>)$/i;
// <img src="url..." optional width optional height optional alt optional title
var img_white = /^(<img\ssrc="(https?:\/\/|\/)[-A-Za-z0-9+&@#\/%?=~_|!:,.;\(\)*[\]$]+"(\swidth="\d{1,3}")?(\sheight="\d{1,3}")?(\salt="[^"<>]*")?(\stitle="[^"<>]*")?\s?\/?>)$/i;
var video_white = /<video(.*?)>/;
function sanitizeTag(tag) {
if (tag.match(basic_tag_whitelist) || tag.match(a_white) || tag.match(img_white) || tag.match(iframe_youtube) || tag.match(iframe_vimeo) || tag.match(iframe_soundcloud) || tag.match(iframe_googlestorage) || tag.match(video_white)) {
return tag;
} else {
return "";
}
}
/// <summary>
/// attempt to balance HTML tags in the html string
/// by removing any unmatched opening or closing tags
/// IMPORTANT: we *assume* HTML has *already* been
/// sanitized and is safe/sane before balancing!
///
/// adapted from CODESNIPPET: A8591DBA-D1D3-11DE-947C-BA5556D89593
/// </summary>
function balanceTags(html) {
if (html == "")
return "";
var re = /<\/?\w+[^>]*(\s|$|>)/g;
// convert everything to lower case; this makes
// our case insensitive comparisons easier
var tags = html.toLowerCase().match(re);
// no HTML tags present? nothing to do; exit now
var tagcount = (tags || []).length;
if (tagcount == 0)
return html;
var tagname, tag;
var ignoredtags = "<p><img><br><li><hr>";
var match;
var tagpaired = [];
var tagremove = [];
var needsRemoval = false;
// loop through matched tags in forward order
for (var ctag = 0; ctag < tagcount; ctag++) {
tagname = tags[ctag].replace(/<\/?(\w+).*/, "$1");
// skip any already paired tags
// and skip tags in our ignore list; assume they're self-closed
if (tagpaired[ctag] || ignoredtags.search("<" + tagname + ">") > -1)
continue;
tag = tags[ctag];
match = -1;
if (!/^<\//.test(tag)) {
// this is an opening tag
// search forwards (next tags), look for closing tags
for (var ntag = ctag + 1; ntag < tagcount; ntag++) {
if (!tagpaired[ntag] && tags[ntag] == "</" + tagname + ">") {
match = ntag;
break;
}
}
}
if (match == -1)
needsRemoval = tagremove[ctag] = true; // mark for removal
else
tagpaired[match] = true; // mark paired
}
if (!needsRemoval)
return html;
// delete all orphaned tags from the string
var ctag = 0;
html = html.replace(re, function (match) {
var res = tagremove[ctag] ? "" : match;
ctag++;
return res;
});
return html;
}
})();

Event Timeline