Please implement support for Blind Key Rotation (privacy feature)
#398
Closed
opened 5 years ago by kaniini
·
3 comments
No Branch/Tag Specified
paginate-search-init
main
s3
fix-delete-user
timeline-cli
blog-title
signature
remove-dup-images
ldap-non-anon
drone-ci
DearRude/force-lang
igalic/go/async-all-mut
go/async
floreal/translations-update
missing-docs
RAOF/fix-arm64-build
epsilon-phase/authorized-fetch
upgrade
improve-the-editor-once-again
igalic/feat/custom-fairing-domains
feature/ldap
test/dotenv_error
fix-mobile-margin
0.7.2
0.7.0
0.2.0-alpha-1
0.3.0-alpha-2
0.4.0-alpha-4
0.5.0
0.6.0
0.7.1
Labels
Clear labels
Related to the REST API
Code running on the server
Stuff related to Federation
Related to the front-end
Translations, and related code
More about project management or code than the project itself
The building, or installation process of Plume
Something isn't working
We need to talk
New feature or request
This is a new feature
Compatibility with different browsers, readers and OS
Related to an external package that Plume uses
UI/UX related issues and PRs
Good for newcomers
Extra attention is needed
Issues affecting only mobile UX
How elements're rendered out for the end user
Something else needs to be fixed first
This issue or pull request already exists
This PR is not complete yet
Issues concern a limited number of instances
This doesn't seem right
Need to be discussed by the community (on Loomio)
This PR is ready to be reviewed
Proposed ideas worth considering
This is issue has been created after a vote on Loomio
This will not be worked on
Apply labels
A: API
Related to the REST API
A: Backend
Code running on the server
A: Federation
Stuff related to Federation
A: Front-End
Related to the front-end
A: I18N
Translations, and related code
A: Meta
More about project management or code than the project itself
A: Security
Build
The building, or installation process of Plume
C: Bug
Something isn't working
C: Discussion
We need to talk
C: Enhancement
New feature or request
C: Feature
This is a new feature
Compatibility
Compatibility with different browsers, readers and OS
Dependency
Related to an external package that Plume uses
Design
UI/UX related issues and PRs
Documentation
Good first issue
Good for newcomers
Help welcome
Extra attention is needed
Mobile
Issues affecting only mobile UX
Rendering
How elements're rendered out for the end user
S: Blocked
Something else needs to be fixed first
S: Duplicate
This issue or pull request already exists
S: Incomplete
This PR is not complete yet
S: Instance specific
Issues concern a limited number of instances
S: Invalid
This doesn't seem right
S: Needs Voting/Discussion
Need to be discussed by the community (on Loomio)
S: Ready for review
This PR is ready to be reviewed
Suggestion
Proposed ideas worth considering
S: Voted on Loomio
This is issue has been created after a vote on Loomio
S: Wontfix
This will not be worked on
No Label
A: API
A: Backend
A: Federation
A: Front-End
A: I18N
A: Meta
A: Security
Build
C: Bug
C: Discussion
C: Enhancement
C: Feature
Compatibility
Dependency
Design
Documentation
Good first issue
Help welcome
Mobile
Rendering
S: Blocked
S: Duplicate
S: Incomplete
S: Instance specific
S: Invalid
S: Needs Voting/Discussion
S: Ready for review
Suggestion
S: Voted on Loomio
S: Wontfix
Milestone
Set milestone
Clear milestone
No items
No Milestone
Assignees
Assign users
Clear assignees
No Assignees
2 Participants
Notifications
Due Date
The due date is invalid or out of range. Please use the format 'yyyy-mm-dd'.
No due date set.
Dependencies
No dependencies set.
Reference: Plume/Plume#398
Reference in New Issue
There is no content yet.
Delete Branch '%!s(<nil>)'
Deleting a branch is permanent. It CANNOT be undone. Continue?
No
Yes
Background
Blind Key Rotation is a mitigation for the problem that JSON-LD Linked Data Signatures are irrevocable. It is also useful (albeit less so) in the context of HTTP Signatures, since HTTP Signatures only sign headers and not the object itself, and are also detached from the object.
As Plume implements JSON-LD Linked Data Signatures, implementing Blind Key Rotation is important for resolving trust and safety issues with this signature scheme!
Implementation - receiving objects
Supporting Blind Key Rotation in the validation pipeline is simple enough: if a signature validation fails, refetch the remote actor and recheck the signature accordingly.
This would be done here:
80a4dae8bd/src/routes/instance.rs (L188-L193)
Implementation - deleting objects
Supporting Blind Key Rotation to enhance the deniability of deleted objects is also simple enough: send the
Delete
signed with the original key and then silently replace the keypair. The new keys will be fetched when the user publishes new content.I'm not quite certain where to implement this part, but it is probably not that hard to implement.
Questions?
Contact me on fediverse: https://pleroma.site/kaniini
An activity pub user has also opened a small bounty for this https://social.holdmybeer.solutions/objects/44515888-e4c2-4043-b0e8-96e15b7a254c
So if I understood well:
Delete
(doUndo
s count too?) : sign with the current key, then regenerate a new oneAm I right?
I have a few more questions:
original key
(in deleting Object) need to be the one which was used in theCreate
activity, or can it be an other key assuming something else was deleted between creation and deletion of this Object?https://<domain>/@/<user>/#main-key
. Should this value be updated whenever a new key is issued, or not?Delete
activity is sent, or some time later (how much?) to make sure instances who did not know the key for thisDelete
can still fetch it to validate the deletion?@fdb-hiroshima
Your understanding is basically correct. I would suggest rotating the key a little while after the
Delete
so if there's multipleDelete
activities you can batch them together.The original key should be whatever key would normally sign the Delete.
The key ID should not ever be updated when rotated.