rollup-plugin-sri
Because web security should not be difficult.
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This plugin adds subresource integrity attributes to all resources imported by your html files.
Usage
Just use this plugin together with another plugin that outputs an html file, like @rollup/plugin-html.
It will then generate integrity
and crossorigin
attributes for all script tags and all link rel="stylesheet" tags.
import html from '@rollup/plugin-html'
import sri from 'rollup-plugin-sri'
export default {
input: 'index.js',
output: {
file: 'out.js',
format: 'es'
},
plugins: [html(), sri()]
}
Examples
Basic
You might have a script tag in your html to include a javascript file like this:
<script src="index.js"></script>
Which then gets turned into this:
<script
src="index.js"
integrity="sha512-nbecVo2rGsF6Q3d4sK/sF4AmMv3eIxXpjk6Larv6iDUWeaRjjYL44RyK45vPO3Aav/ep6qTgbUAebC20uEGq8g== sha384-zFyvltviTuMi40r9uTjP6Cc/kdJy3hboH2SbOT2Q7UaXK8c4+DtTEAG16VM0H4tP"
crossorigin="anonymous"
></script>
External dependencies
Let's say you're using Bootstrap on your page, but it get dynamically injected so you can't set the integrity attribute yourself.
The html will then look something like this:
<link
rel="stylesheet"
href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.0/css/bootstrap.min.css"
/>
This plugin will turn it into the following:
<link
rel="stylesheet"
href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.0/css/bootstrap.min.css"
integrity="sha384-9aIt2nRpC12Uk9gS9baDl411NQApFmC26EwAOH8WgZl5MYYxFfc+NcPb1dKGj7Sk"
crossorigin="anonymous"
/>
Multiple hashing algorithms
You can also specify any number of hashing algorithms to be used by the plugin as long as they are supported by your current version of nodejs.
import html from '@rollup/plugin-html'
import sri from 'rollup-plugin-sri'
export default {
input: 'index.js',
output: {
file: 'out.js',
format: 'es'
},
plugins: [
html(),
sri({
algorithms: ['sha1', 'md5', 'sha512']
})
]
}
This config will generate an output like this:
There are a few things to note though:
- You can in theory use any hashing algorithm you want, however most browser only support the sha family of hashing algorithms like sha256, sha384 and sha512
- Browser vendors are actively discouraged from using
md5
and sha1
as they are not considered to be secure enough.
Most modern browser won't accept them at all.
<script
src="index.js"
integrity="sha1-uwq/zzhXJzUJKIrPcWeL6RkTC8I= md5-illu96GKKoep5d+RUptcBw== sha512-k2VO1XnXo7MN/pqEHWCJYyn4D2d5z0FSDRvIrz4WPmw4VTPNhnSMJRvAwz2Llaij45VU35+eO3eQjydVhGggLg=="
crossorigin="anonymous"
></script>
Options
For the most up-to-date version of the options see the autogenerated docs.
Optional
active
Type: boolean
default
true
Can be used to disable the plugin, for example when used together with hot-module-reloading.
Optional
algorithms
Type: Array[string]
default
["sha384"]
A list of hashing algorithms to use when computing the integrity attribute.
The hashing algorithm has to be supported by the nodejs version you're running on and by the Browser you're targeting.
Browsers will ignore unknown hashing functions.
Standard hash functions as defined in the subresource integrity specification are: sha256
, sha384
and sha512
.
NOTE: While browser vendors are free to support more algorithms than those stated above,
they generally do not accept sha1
and md5
hashes.
Optional
crossorigin
Type: "anonymous" | "use-credentials"
default
"anonymous"
Specifies the value for the crossorigin attribute.
This attribute has to be set to prevent cross-origin data leakage.
The default value anonymous
should be okay for normal use.
see: the W3C spec for details.
Optional
selectors
Type: Array[string]
default
["script","link[rel=stylesheet]"]
A list of strings you can provide that the plugin will use to match html tags with.
It will then try to compute an integrity attribute for the matched tag.
Currently it only matches script tags and link with rel=stylesheet as per specification.
see the W3C spec for more information.
The selector syntax is the same as jQuery's.
Contributing
For bug reports or feature requests please create an issue on github.
When working on a feature contribution, please ensure the following things:
- Keep you code clear and readable.
- Write unit tests for your feature (run
yarn test
). - Use the convetional-commits style when writing commit messages. ( When you're unsure about how to do this, type
yarn commit
) And you'll be guided through the process. - Use appropriate commit types, When adding tests use
test:
when adding a feature use feat:
etc. - Split up the files you commit logically not by workday or something else, for example all test belonging to a new feature should be in their own commit and not bunched together with other changes or tests for other features.
License
MIT