ecto/bleach

:no_entry_sign: minimalistic HTML sanitizer for node.js

bleach

Sanitize your HTML the easy way!

install

npm install bleach

test

vows --spec test/*

example

Basic:

var bleach = require('bleach');

var html = bleach.sanitize(aBunchOfHTML);

console.log(html);

Advanced:

var bleach = require('bleach');

var whitelist = [
  'a',
  'b',
  'i',
  'em',
  'strong'
]

var options = {
  mode: 'white',
  list: whitelist
}

var html = bleach.sanitize(aBunchOfHTML, options);

console.log(html);

usage

bleach.sanitize(html, options)

Runs HTML through sanitizer and returns sanitized HTML as string.

options may contain the following optional attributes:

• mode may be set to 'white' or 'black'
• list is an array containing tags to match against

whitemode will remove all tags from html, excluding those in list

blackmode will remove all tags found in list that are found in html

bleach.analyze(html)

Will extract all tags from HTML and return an array of JSON objects. Example return:

[
  {
    full: '<div id="post-119477">',
    name: 'div',
    attr: [
      "id": "post-119477"
    ]
  },
  ...
]

bleach.filter(html, filters)

SEXY FUN TIME

var nyanFilter = function(input){
  return input.replace('cats', 'nyannyannyan');
}

console.log(
  bleach.filter('cats', nyanFilter)
);

// nyannyannyan

var cutFilter = function(input){
  return input.slice(0, 3);
}

console.log(
  bleach.filter('cats', [
    nyanFilter,
    cutFilter
  ])
);

// nyan

You may also define longer filters and include them in the ./node_modules/bleach/filters directory. A sample filter is included to convert YouTube flash embed objects to iDevice-compatible YouTube iframes.

var html = '<object classid="clsid:d27cdb6e-ae6d-11cf-96b8-444553540000" width="420" height="315" codebase="http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=6,0,40,0"><param name="allowFullScreen" value="true"><param name="allowscriptaccess" value="always"><param name="src" value="http://www.youtube.com/v/aU079Mdkenw?version=3&amp;hl=en_US"><param name="allowfullscreen" value="true"><embed type="application/x-shockwave-flash" width="420" height="315" src="http://www.youtube.com/v/aU079Mdkenw?version=3&amp;hl=en_US" allowscriptaccess="always" allowfullscreen="true" id="s_media_1_0" name="s_media_1_0"></object>';

console.log(
  bleach.filter(html, 'youtube')
);

// <iframe type="text/html" frameborder="0" scrolling="no" allowfullscreen src="http://youtube.com/embed/aU079Mdkenw"></iframe>

Refer to the filters directory for the template.

disclaimer

This is not a port of the Python bleach library - in fact their implementations are very different.

license

(The MIT License)

Copyright (c) 2011 Cam Pedersen [email protected]

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

bleach's Issues

Take a look

[https://srcclr.com/bleach/javascript/npm/c-12769/vulnerabilities]

Wrong Analyze

Hello together,

I was just wondering, whether I misunderstand your tool, or foud a bug.

When I run the following code in Node.JS:

const bleach = require('bleach'),
util =  require('util');

console.log(
  "process.versions: %s\n\n", 
  util.inspect(process.versions)
);

console.log(
  "bleach.analyze.result: %s", 
  util.inspect(
    bleach.analyze(`
<a 
  href="#" 
  taget="_blank" 
  onclick="alert('hallo'); return false;"
>Klick mich!</a>
    `), 
     {
       depth: null
     }
   )
);

I get the following output:

process.versions: { http_parser: '2.8.0',
  node: '9.11.2',
  v8: '6.2.414.46-node.23',
  uv: '1.19.2',
  zlib: '1.2.11',
  ares: '1.13.0',
  modules: '59',
  nghttp2: '1.32.0',
  napi: '3',
  openssl: '1.0.2o',
  icu: '61.1',
  unicode: '10.0',
  cldr: '33.0',
  tz: '2018c' }


bleach.analyze.result: [ { full: '<a href="#" taget="_blank" onclick="alert(\'hallo\'); return false;">',
    name: 'a',
    attr: 
     [ { name: 'href', value: '#' },
       { name: 'taget', value: '_blank' },
       { name: 'onclick', value: 'alert(\'hallo\');' },
       { name: 'return' },
       { name: 'false;"' } ] },
  { full: '</a>', name: 'a', attr: [] } ]

In the section

     [
       /* ..., */
       { name: 'onclick', value: 'alert(\'hallo\');' },
       { name: 'return' },
       { name: 'false;"' } ] },
     ]

I would expect the result to be:

     [
       /* ..., */
       { name: 'onclick', value: 'alert(\'hallo\'); return false;"' } ] },
     ]

Is that a wrong expectation?

Kind regards,
wusala01

The `delete match;` in youtube.js is invalid in strict mode

https://github.com/ecto/bleach/blob/master/filters/youtube.js#L10

This line of code is invalid in strict mode, which will prevent the library from being used with many JavaScript tools. It should be safe to just remove the delete statement.

Avoid synchronous I/O in filter method

A web site that used the filter method to service a web request would have a big drop in throughput as it uses blocking I/O. You should consider caching the filters or providing an async method.

Not able to sanitize URL : http://localhost:3000/tv/%3Cscript%3Easd12569%3C/script%3E using bleach

Hi,

I am not able to sanitize encoded URL as see below:

http://localhost:3000/tv/%3Cscript%3Easd12569%3C/script%3E.

we are also to sanitize if url is coming as : http://localhost:3000/tv/<script>asd12569</script>

Can you please help on this how this can be sanitize as from request itself we are getting URL in this manner.

Support entity conversion

There should be an option which, if set to true, causes sanitize() to convert certain characters to HTML entities