# Permission System 2.0
## Background
This PR migrates the extension permission system to [the new `PermissionController`](https://github.com/MetaMask/snaps-skunkworks/tree/main/packages/controllers/src/permissions).
The original permission system, based on [`rpc-cap`](https://github.com/MetaMask/rpc-cap), introduced [`ZCAP-LD`](https://w3c-ccg.github.io/zcap-ld/)-like permissions to our JSON-RPC stack.
We used it to [implement](https://github.com/MetaMask/metamask-extension/pull/7004) what we called "LoginPerSite" in [version 7.7.0](https://github.com/MetaMask/metamask-extension/releases/tag/v7.7.0) of the extension, which enabled the user to choose which accounts, if any, should be exposed to each dapp.
While that was a worthwhile feature in and of itself, we wanted a permission _system_ in order to enable everything we are going to with Snaps.
Unfortunately, the original permission system was difficult to use, and necessitated the creation of the original `PermissionsController` (note the "s"), which was more or less a wrapper for `rpc-cap`.
With this PR, we shake off the yoke of the original permission system, in favor of the modular, self-contained, ergonomic, and more mature permission system 2.0.
Note that [the `PermissionController` readme](https://github.com/MetaMask/snaps-skunkworks/tree/main/packages/controllers/src/permissions/README.md) explains how the new permission system works.
The `PermissionController` and `SubjectMetadataController` are currently shipped via `@metamask/snap-controllers`. This is a temporary state of affairs, and we'll move them to `@metamask/controllers` once they've landed in prod.
## Changes in Detail
First, the changes in this PR are not as big as they seem. Roughly half of the additions in this PR are fixtures in the test for the new migration (number 68), and a significant portion of the remaining ~2500 lines are due to find-and-replace changes in other test fixtures and UI files.
- The extension `PermissionsController` has been deleted, and completely replaced with the new `PermissionController` from [`@metamask/snap-controllers`](https://www.npmjs.com/package/@metamask/snap-controllers).
- The original `PermissionsController` "domain metadata" functionality is now managed by the new `SubjectMetadataController`, also from [`@metamask/snap-controllers`](https://www.npmjs.com/package/@metamask/snap-controllers).
- The permission activity and history log controller has been renamed `PermissionLogController` and has its own top-level state key, but is otherwise functionally equivalent to the existing implementation.
- Migration number 68 has been added to account for the new state changes.
- The tests in `app/scripts/controllers/permissions` have been migrated from `mocha` to `jest`.
Reviewers should focus their attention on the following files:
- `app/scripts/`
- `metamask-controller.js`
- This is where most of the integration work for the new `PermissionController` occurs.
Some functions that were internal to the original controller were moved here.
- `controllers/permissions/`
- `selectors.js`
- These selectors are for `ControllerMessenger` selector subscriptions. The actual subscriptions occur in `metamask-controller.js`. See the `ControllerMessenger` implementation for details.
- `specifications.js`
- The caveat and permission specifications are required by the new `PermissionController`, and are used to specify the `eth_accounts` permission and its JSON-RPC method implementation.
See the `PermissionController` readme for details.
- `migrations/068.js`
- The new state should be cross-referenced with the controllers that manage it.
The accompanying tests should also be thoroughly reviewed.
Some files may appear new but have just moved and/or been renamed:
- `app/scripts/lib/rpc-method-middleware/handlers/request-accounts.js`
- This was previously implemented in `controllers/permissions/permissionsMethodMiddleware.js`.
- `test/mocks/permissions.js`
- A truncated version of `test/mocks/permission-controller.js`.
Co-authored-by: Mark Stacey <markjstacey@gmail.com>
`eth_getProof` is an unpermissioned, read-only RPC method for getting account-related Merkle proofs, specified here: https://eips.ethereum.org/EIPS/eip-1186
It's been supported by major Ethereum clients, and Infura, for some time. By adding it to the safe methods list, we enable this method for our users.
This PR introduces the new approval controller to the extension codebase. We use it for the permissions controller's pending approval functionality.
The approval controller sets us up for a new pattern of requesting and managing user confirmations in RPC methods. Along with the generic RPC method middleware, the approval controller will allow us to eliminate our message managers, and decouple various method handlers from our provider stack, making the implementations more portable between the extension and mobile.
* @metamask/inpage-provider@^8.0.0
* Replace public config store with JSON-RPC notifications
* Encapsulate notification permissioning in permissions controller
* Update prefix of certain internal RPC methods and notifications
* Add accounts to getProviderState
* Send accounts with isUnlocked notification (#10007)
* Rename provider streams, notify provider of stream failures (#10006)
This method was accidentally broken with the introduction of the
permissions controller, as this was missing from the list of safe
methods.
It is now included in the list of safe methods.
Fixes#8993
Implement `eth_decrypt` and `eth_getEncryptionPublicKey`. This allows decryption backed by the user's private key. The message decryption uses a confirmation flow similar to the messaging signing flow, where the message to be decrypted is also able to be decrypted inline for the user to read directly before confirming.
Update accounts permission history on accountsChanged
Create PermissionsLogController
Fix permissions activity log pruning
Add selectors, background hooks for better UX
Make selected account the first account returned
Use enums for store keys in log controller
Add last selected address history to PreferencesController
