Add ERC: Cancelation for ERC-7540 Tokenized Vaults

ERCS/erc-x.md

@@ -0,0 +1,360 @@
+---
+eip: x
+title: Cancelation for ERC-7540 Tokenized Vaults
+description: Extension of ERC-7540 with cancelation support
+author: Jeroen Offerijns (@hieronx), Vikram Arun (@vikramarun)
+discussions-to: TODO
+status: Draft
+type: Standards Track
+category: ERC
+created: 2025-02-18
+requires: 165, 7540
+---
+
+## Abstract
+
+The following standard extends [ERC-7540](./eip-7540.md) by adding support for asynchronous cancelation flows.
+
+## Motivation
+
+Shares or assets locked for Requests can be stuck in the Pending state. For some use cases, such as redeeming from a pool of long-dated real-world assets, this can take a considerable amount of time.
+
+This standard expands the scope Asynchronous ERC-7540 Vaults by adding cancelation support.
+
+## Specification
+
+### Definitions:
+
+The existing definitions from [ERC-7540](./eip-7540.md) apply.
+
+### Cancelation Lifecycle
+
+After submission, cancelation Requests go through Pending, Claimable, and Claimed stages. An example lifecycle for a deposit cancelation Request is visualized in the table below.
+
+| **State**   | **User**                         | **Vault** |
+|-------------|---------------------------------|-----------|
+| Pending     | `cancelDepositRequest(requestId, controller)` | `pendingCancelDepositRequest[controller] = true` |
+| Claimable   |                                 | *Internal cancelation fulfillment*:  `pendingCancelDepositRequest[controller] = false`; `claimableCancelDepositRequest[controller] = assets` |
+| Claimed     | `claimCancelDepositRequest(requestId, receiver, controller)`      | `claimableDepositRequest[controller] -= assets`; `asset.balanceOf[receiver] += assets` |
+
+Requests MUST NOT skip or otherwise short-circuit the Claim state. In other words, to initiate and claim a Request, a user MUST call both cancel* and the corresponding Claim function separately, even in the same block. Vaults MUST NOT "push" tokens onto the user after a Request, users MUST "pull" the tokens via the Claim function.
+
+Requests MAY skip straight from the Pending to the Claimable stage, in the case of synchronous cancelation flows.
+
+While a deposit cancelation Request is Pending, new deposit Requests are blocked. Likewise, while a redeem cancelation Request is Pending, new redeem Requests are blocked.
+
+### Methods
+
+#### cancelDepositRequest
+
+Submits a Request for asynchronous deposit cancelation. This places the Request in Pending state, with a corresponding increase in `pendingCancelDepositRequest` for the full amount of the pending deposit Request. 
+
+When the cancelation is Pending, new deposit Requests are blocked and `requestDeposit` MUST revert.
+
+When the cancelation is Claimable, `claimableCancelDepositRequest` will be increased for the `controller`. `claimCancelDepositRequest` can subsequently be called by `controller` to receive `assets`. A Request MAY transition straight to Claimable state but MUST NOT skip the Claimable state.
+
+`controller` MUST equal `msg.sender` unless the `controller` has approved the `msg.sender` as an operator.
+
+MUST emit the `CancelDepositRequest` event.
+
+```yaml
+- name: cancelDepositRequest
+  type: function
+  stateMutability: nonpayable
+
+  inputs:
+    - name: requestId
+      type: uint256
+    - name: controller
+      type: address
+  outputs:
+```
+
+#### pendingCancelDepositRequest
+
+Whether the given `requestId` and `controller` have a pending deposit cancelation Request.
+
+MUST NOT show any variations depending on the caller.
+
+MUST NOT revert unless due to integer overflow caused by an unreasonably large input.
+
+```yaml
+- name: pendingCancelDepositRequest
+  type: function
+  stateMutability: view
+
+  inputs:
+    - name: requestId
+      type: uint256
+    - name: controller
+      type: address
+
+  outputs:
+    - name: isPending
+      type: bool
+```
+
+#### claimableCancelDepositRequest
+
+The amount of `assets` in Claimable cancelation state for the `controller` to claim.
+
+MUST NOT show any variations depending on the caller.
+
+MUST NOT revert unless due to integer overflow caused by an unreasonably large input.
+
+```yaml
+- name: claimableCancelDepositRequest
+  type: function
+  stateMutability: view
+
+  inputs:
+    - name: requestId
+      type: uint256
+    - name: controller
+      type: address
+
+  outputs:
+    - name: assets
+      type: uint256
+```
+
+#### claimCancelDepositRequest
+
+Claims the deposit cancelation Request with `requestId` and `controller`.
+
+Transfers `assets` to `receiver`.
+
+`controller` MUST equal `msg.sender` unless the `controller` has approved the `msg.sender` as an operator.
+
+MUST emit the `ClaimCancelDepositRequest` event.
+
+```yaml
+- name: claimCancelDepositRequest
+  type: function
+  stateMutability: nonpayable
+
+  inputs:
+    - name: requestId
+      type: uint256
+    - name: receiver
+      type: address
+    - name: controller
+      type: address
+  outputs:
+```
+
+#### cancelRedeemRequest
+
+Submits a Request for asynchronous redeem cancelation. This places the Request in Pending state, with a corresponding increase in `pendingCancelRedeemRequest` for the full amount of the pending redeem Request. 
+
+When the cancelation is Pending, new redeem Requests are blocked and `requestRedeem` MUST revert.
+
+When the cancelation is Claimable, `claimableCancelRedeemRequest` will be increased for the `controller`. `claimCancelRedeemRequest` can subsequently be called by `controller` to receive `shares`. A Request MAY transition straight to Claimable state but MUST NOT skip the Claimable state.
+
+`controller` MUST equal `msg.sender` unless the `controller` has approved the `msg.sender` as an operator.
+
+MUST emit the `CancelRedeemRequest` event.
+
+```yaml
+- name: cancelRedeemRequest
+  type: function
+  stateMutability: nonpayable
+
+  inputs:
+    - name: requestId
+      type: uint256
+    - name: controller
+      type: address
+  outputs:
+```
+
+#### pendingCanceRedeemRequest
+
+Whether the given `requestId` and `controller` have a pending redeem cancelation Request.
+
+MUST NOT show any variations depending on the caller.
+
+MUST NOT revert unless due to integer overflow caused by an unreasonably large input.
+
+```yaml
+- name: pendingCanceRedeemRequest
+  type: function
+  stateMutability: view
+
+  inputs:
+    - name: requestId
+      type: uint256
+    - name: controller
+      type: address
+
+  outputs:
+    - name: isPending
+      type: bool
+```
+
+#### claimableCancelRedeemRequest
+
+The amount of `shares` in Claimable cancelation state for the `controller` to claim.
+
+MUST NOT show any variations depending on the caller.
+
+MUST NOT revert unless due to integer overflow caused by an unreasonably large input.
+
+```yaml
+- name: claimableCancelRedeemRequest
+  type: function
+  stateMutability: view
+
+  inputs:
+    - name: requestId
+      type: uint256
+    - name: controller
+      type: address
+
+  outputs:
+    - name: shares
+      type: uint256
+```
+
+#### claimCancelRedeemRequest
+
+Claims the redeem cancelation Request with `requestId` and `controller`.
+
+Transfers `assets` to `receiver`.
+
+`controller` MUST equal `msg.sender` unless the `controller` has approved the `msg.sender` as an operator.
+
+MUST emit the `ClaimCancelRedeemRequest` event.
+
+```yaml
+- name: claimCancelRedeemRequest
+  type: function
+  stateMutability: nonpayable
+
+  inputs:
+    - name: requestId
+      type: uint256
+    - name: receiver
+      type: address
+    - name: owner
+      type: address
+  outputs:
+```
+
+### Events
+
+#### CancelDepositRequest
+
+`controller` has requested cancelation of their deposit Request with request ID `requestId`. `sender` is the caller of the `cancelDepositRequest` which may not be equal to the `controller`.
+
+MUST be emitted when a deposit cancelation Request is submitted using the `cancelDepositRequest` method.
+
+```yaml
+- name: CancelDepositRequest
+  type: event
+
+  inputs:
+    - name: controller
+      indexed: true
+      type: address
+    - name: requestId
+      indexed: true
+      type: uint256
+    - name: sender
+      indexed: false
+      type: address
+```
+
+#### CancelDepositClaim
+
+`controller` has claimed their deposit cancelation Request with request ID `requestId`. `receiver` is the destination of the `assets`. `sender` is the caller of the `claimCancelDepositRequest` which may not be equal to the `controller`.
+
+MUST be emitted when a deposit cancelation Request is submitted using the `claimCancelDepositRequest` method.
+
+```yaml
+- name: CancelDepositClaim
+  type: event
+
+  inputs:
+    - name: controller
+      indexed: true
+      type: address
+    - name: receiver
+      indexed: true
+      type: address
+    - name: requestId
+      indexed: true
+      type: uint256
+    - name: sender
+      indexed: false
+      type: address
+    - name: assets
+      indexed: false
+      type: uint256
+```
+
+#### CancelRedeemRequest
+
+`controller` has requested cancelation of their deposit Request with request ID `requestId`. `sender` is the caller of the `cancelRedeemRequest` which may not be equal to the `controller`.
+
+MUST be emitted when a deposit cancelation Request is submitted using the `cancelRedeemRequest` method.
+
+```yaml
+- name: CancelRedeemRequest
+  type: event
+
+  inputs:
+    - name: controller
+      indexed: true
+      type: address
+    - name: requestId
+      indexed: true
+      type: uint256
+    - name: sender
+      indexed: false
+      type: address
+```
+
+#### CancelRedeemClaim
+
+`controller` has claimed their redeem cancelation Request with request ID `requestId`. `receiver` is the destination of the `shares`. `sender` is the caller of the `claimCancelRedeemRequest` which may not be equal to the `controller`.
+
+MUST be emitted when a redeem cancelation Request is submitted using the `claimCancelRedeemRequest` method.
+
+```yaml
+- name: CancelRedeemClaim
+  type: event
+
+  inputs:
+    - name: controller
+      indexed: true
+      type: address
+    - name: receiver
+      indexed: true
+      type: address
+    - name: requestId
+      indexed: true
+      type: uint256
+    - name: sender
+      indexed: false
+      type: address
+    - name: shares
+      indexed: false
+      type: uint256
+```
+
+### [ERC-165](./eip-165.md) support
+
+Smart contracts implementing this Vault standard MUST implement the [ERC-165](./eip-165.md) `supportsInterface` function.
+
+Asynchronous deposit Vaults with cancelation support MUST return the constant value `true` if `0x8bf840e3` is passed through the `interfaceID` argument.
+
+Asynchronous redemption Vaults with cancelation support MUST return the constant value `true` if `0xe76cffc7` is passed through the `interfaceID` argument.
+
+## Backwards Compatibility
+
+The interface is fully backwards compatible with [ERC-7540](./eip-7540.md).
+
+## Copyright
+
+Copyright and related rights waived via [CC0](../LICENSE.md).