Sub-resource integrity #521
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This is the start of the implementation of miracle2k#494 Currently only tested on Python 3.7, missing unit tests and documentation. Basic idea is to extend the Bundle.urls() function to return a list of dictionaries {'uri': <same as before>, 'sri': <hash>} but only when requested (to not break existing users). A dict is used instead of a tuple to allow adding other values in the future. Currently only works for local resources.
Part of implementing miracle2k#494
This makes it work better with nested bundles and removes the possibility of mixed settings. This commit also adds unit tests for the bundle class. Part of implementing miracle2k#494
|
Sorry for the delay in getting this merged. Good work. |
This was referenced May 12, 2021
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
This pull request implements #494, by adding a flag to the Bundle.urls() method (calculate_sri) that defaults to false. When set to true it changes the return value from a list of URIs to a list of (using syntax based on Python 3's typing module):
{'uri': str, sri: Optional[str]}For example:
[{'uri': '/a', 'sri': 'sha384-OLBgp1GsljhM2TJ+sbHjaiH9txEUvgdDTAzHv2P24donTt6/529l+9Ua0vFImLlb'}]This is then used by the jinja2 module to expose a new variable ASSERT_SRI. that can be used something like this:
Note that the SRI is not computed for remote resources, in that case None is returned. This should be handled properly, but obviously it is something that the template write will have to deal with if it can happen in their environment (and they also want to use the integrity features for local resources).
This could be extended in the future to download and calculate the hash for remote resources, but there is an inherent trust/security issue, should that resource change between builds when you don't expect it to, so I'm not sure it would be a good idea.
This has been tested on Python 2.7 and 3.7, I do not have easy ability to test anything else, and there seems to be some issue with failing unit tests in general for this project in the Travis CI setup.