README.md

integrity

Simple tool to generate the integrity attribute for subresource integrity.

Example

Let's say you want to use Backbone from this CDN:

https://cdnjs.cloudflare.com/ajax/libs/backbone.js/1.2.3/backbone-min.js

Just pass that address to the tool:

./integrity https://cdnjs.cloudflare.com/ajax/libs/backbone.js/1.2.3/backbone-min.js

And then use the output tu build the script tag:

<script crossorigin="anonymous" integrity="sha384-kgH1F06klaG52/uQEQlpP5QZ9tbJZgcU4omvs1DRSHaJGVZWp//NYtoi93ZmGday" src="https://cdnjs.cloudflare.com/ajax/libs/backbone.js/1.2.3/backbone-min.js"></script>

Voilà! You're now safe from unexpected manipulation. The resource you asked for is going to be the one you wanted.

integrity

#!/usr/bin/env bash

main() {
  local URL=$1

  if [ -z "$URL" ]; then
    echo 'No URL was given.' 1>&2
    return 1
  fi

  local DIGEST=$(
    curl -s $URL |
    openssl dgst -sha384 -binary |
    openssl enc -base64 -A
  )

  echo "sha384-$DIGEST"

  return 0
}

main $1