Delegatable resolver

README.md

@@ -176,8 +176,8 @@ yarn pub
 5. Create a "Release Candidate" [release](https://docs.github.com/en/repositories/releasing-projects-on-github/about-releases) on GitHub. This will be of the form `v1.2.3-RC0`. This tagged commit is now subject to our bug bounty.
 6. Have the tagged commit audited if necessary
 7. If changes are required, make the changes and then once ready for review create another GitHub release with an incremented RC value `v1.2.3-RC0` -> `v.1.2.3-RC1`. Repeat as necessary.
-8. Deploy to testnet. Open a pull request to merge the deploy artifacts into 
-the `feature` branch. Get someone to review and approve the deployment and then merge. You now MUST merge this branch into `staging` branch.
+8. Deploy to testnet. Open a pull request to merge the deploy artifacts into
+   the `feature` branch. Get someone to review and approve the deployment and then merge. You now MUST merge this branch into `staging` branch.
 9. Create GitHub release of the form `v1.2.3-testnet` from the commit that has the new deployment artifacts.
 10. If any further changes are needed, you can either make them on the existing feature branch that is in sync or create a new branch, and follow steps 1 -> 9. Repeat as necessary.
 11. Make Deployment to mainnet from `staging`. Commit build artifacts. You now MUST merge this branch into `main`.

contracts/resolvers/DelegatableResolver.sol

@@ -0,0 +1,121 @@
+pragma solidity >=0.8.4;
+import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
+import "./profiles/ABIResolver.sol";
+import "./profiles/AddrResolver.sol";
+import "./profiles/ContentHashResolver.sol";
+import "./profiles/DNSResolver.sol";
+import "./profiles/InterfaceResolver.sol";
+import "./profiles/NameResolver.sol";
+import "./profiles/PubkeyResolver.sol";
+import "./profiles/TextResolver.sol";
+import "./profiles/ExtendedResolver.sol";
+import "./Multicallable.sol";
+import "./IDelegatableResolver.sol";
+
+/**
+ * A delegated resolver that allows the resolver owner to add an operator to update records of a node on behalf of the owner.
+ * address.
+ */
+contract DelegatableResolver is
+    Ownable,
+    Multicallable,
+    ABIResolver,
+    AddrResolver,
+    ContentHashResolver,
+    DNSResolver,
+    InterfaceResolver,
+    NameResolver,
+    PubkeyResolver,
+    TextResolver,
+    ExtendedResolver
+{
+    using BytesUtils for bytes;
+
+    // Logged when an operator is added or removed.
+    event Approval(
+        bytes32 indexed node,
+        address indexed operator,
+        bytes name,
+        bool approved
+    );
+
+    error NotAuthorized(bytes32 node);
+
+    constructor(address owner) {
+        operators[bytes32(0)][owner] = true;
+        transferOwnership(owner);
+    }
+
+    //node => (delegate => isAuthorised)
+    mapping(bytes32 => mapping(address => bool)) operators;
+
+    /**
+     * @dev Check to see if the operator has been approved by the owner for the node.
+     */
+    function getAuthorizedNode(
+        bytes memory name,
+        uint256 offset,
+        address operator
+    ) public view returns (bytes32 node, bool authorized) {
+        uint256 len = name.readUint8(offset);
+        node = bytes32(0);
+        if (len > 0) {
+            bytes32 label = name.keccak(offset + 1, len);
+            (node, authorized) = getAuthorizedNode(
+                name,
+                offset + len + 1,
+                operator
+            );
+            node = keccak256(abi.encodePacked(node, label));
+        }
+        return (node, authorized || operators[node][operator]);
+    }
+
+    /**
+     * @dev Approve an operator to be able to updated records on a node.
+     */
+    function approve(
+        bytes memory name,
+        address operator,
+        bool approved
+    ) external {
+        (bytes32 node, bool authorized) = getAuthorizedNode(
+            name,
+            0,
+            msg.sender
+        );
+        if (!authorized) {
+            revert NotAuthorized(node);
+        }
+        operators[node][operator] = approved;
+        emit Approval(node, operator, name, approved);
+    }
+
+    function isAuthorised(bytes32 node) internal view override returns (bool) {
+        return msg.sender == owner() || operators[node][msg.sender];
+    }
+
+    function supportsInterface(
+        bytes4 interfaceID
+    )
+        public
+        view
+        virtual
+        override(
+            Multicallable,
+            ABIResolver,
+            AddrResolver,
+            ContentHashResolver,
+            DNSResolver,
+            InterfaceResolver,
+            NameResolver,
+            PubkeyResolver,
+            TextResolver
+        )
+        returns (bool)
+    {
+        return
+            interfaceID == type(IDelegatableResolver).interfaceId ||
+            super.supportsInterface(interfaceID);
+    }
+}

contracts/resolvers/IDelegatableResolver.sol

@@ -0,0 +1,16 @@
+// SPDX-License-Identifier: MIT
+pragma solidity >=0.8.4;
+
+interface IDelegatableResolver {
+    function approve(
+        bytes memory name,
+        address operator,
+        bool approved
+    ) external;
+
+    function getAuthorizedNode(
+        bytes memory name,
+        uint256 offset,
+        address operator
+    ) external returns (bytes32 node, bool authorized);
+}

test/resolvers/TestDelegatableResolver.js

@@ -0,0 +1,136 @@
+const DelegatableResolver = artifacts.require('DelegatableResolver.sol')
+const { encodeName, namehash } = require('../test-utils/ens')
+const { exceptions } = require('../test-utils')
+const { expect } = require('chai')
+
+contract('DelegatableResolver', function (accounts) {
+  let node
+  let encodedname
+  let resolver
+  let signers
+  let deployer
+  let owner
+  let operator
+  let operator2
+
+  beforeEach(async () => {
+    signers = await ethers.getSigners()
+    deployer = await signers[0].getAddress()
+    owner = await signers[1].getAddress()
+    operator = await signers[2].getAddress()
+    operator2 = await signers[3].getAddress()
+    node = namehash('eth')
+    encodedname = encodeName('eth')
+    resolver = await DelegatableResolver.new(owner)
+  })
+
+  describe('supportsInterface function', async () => {
+    it('supports known interfaces', async () => {
+      assert.equal(await resolver.supportsInterface('0x3b3b57de'), true) // IAddrResolver
+      assert.equal(await resolver.supportsInterface('0xf1cb7e06'), true) // IAddressResolver
+      assert.equal(await resolver.supportsInterface('0x691f3431'), true) // INameResolver
+      assert.equal(await resolver.supportsInterface('0x2203ab56'), true) // IABIResolver
+      assert.equal(await resolver.supportsInterface('0xc8690233'), true) // IPubkeyResolver
+      assert.equal(await resolver.supportsInterface('0x59d1d43c'), true) // ITextResolver
+      assert.equal(await resolver.supportsInterface('0xbc1c58d1'), true) // IContentHashResolver
+      assert.equal(await resolver.supportsInterface('0xa8fa5682'), true) // IDNSRecordResolver
+      assert.equal(await resolver.supportsInterface('0x5c98042b'), true) // IDNSZoneResolver
+      assert.equal(await resolver.supportsInterface('0x01ffc9a7'), true) // IInterfaceResolver
+      assert.equal(await resolver.supportsInterface('0x4fbf0433'), true) // IMulticallable
+      assert.equal(await resolver.supportsInterface('0xdd48591c'), true) // IDelegatable
+    })
+
+    it('does not support a random interface', async () => {
+      assert.equal(await resolver.supportsInterface('0x3b3b57df'), false)
+    })
+  })
+
+  describe('addr', async () => {
+    it('permits setting address by owner', async () => {
+      await resolver.methods['setAddr(bytes32,address)'](node, operator, {
+        from: owner,
+      })
+      assert.equal(await resolver.methods['addr(bytes32)'](node), operator)
+    })
+
+    it('forbids setting new address by non-owners', async () => {
+      await exceptions.expectFailure(
+        resolver.methods['setAddr(bytes32,address)'](node, operator, {
+          from: operator,
+        }),
+      )
+    })
+  })
+
+  describe('authorisations', async () => {
+    it('owner is the owner', async () => {
+      assert.equal(await resolver.owner(), owner)
+    })
+
+    it('approves multiple users', async () => {
+      await resolver.approve(encodedname, operator, true, { from: owner })
+      await resolver.approve(encodedname, operator2, true, { from: owner })
+      const result = await resolver.getAuthorizedNode(encodedname, 0, operator)
+      assert.equal(result.node, node)
+      assert.equal(result.authorized, true)
+      assert.equal(
+        (await resolver.getAuthorizedNode(encodedname, 0, operator2))
+          .authorized,
+        true,
+      )
+    })
+
+    it('approves subnames', async () => {
+      const subname = 'a.b.c.eth'
+      await resolver.approve(encodeName(subname), operator, true, {
+        from: owner,
+      })
+      await resolver.methods['setAddr(bytes32,address)'](
+        namehash(subname),
+        operator,
+        {
+          from: operator,
+        },
+      )
+    })
+
+    it('approves users to make changes', async () => {
+      await resolver.approve(encodedname, operator, true, { from: owner })
+      await resolver.methods['setAddr(bytes32,address)'](node, operator, {
+        from: operator,
+      })
+      assert.equal(await resolver.addr(node), operator)
+    })
+
+    it('approves to be revoked', async () => {
+      await resolver.approve(encodedname, operator, true, { from: owner })
+      resolver.methods['setAddr(bytes32,address)'](node, operator2, {
+        from: operator,
+      }),
+        await resolver.approve(encodedname, operator, false, { from: owner })
+      await exceptions.expectFailure(
+        resolver.methods['setAddr(bytes32,address)'](node, operator2, {
+          from: operator,
+        }),
+      )
+    })
+
+    it('does not allow non owner to approve', async () => {
+      await expect(
+        resolver.approve(encodedname, operator, true, { from: operator }),
+      ).to.be.revertedWith('NotAuthorized')
+    })
+
+    it('emits an Approval log', async () => {
+      var tx = await resolver.approve(encodedname, operator, true, {
+        from: owner,
+      })
+      assert.equal(tx.logs.length, 1)
+      assert.equal(tx.logs[0].event, 'Approval')
+      assert.equal(tx.logs[0].args.node, node)
+      assert.equal(tx.logs[0].args.operator, operator)
+      assert.equal(tx.logs[0].args.name, encodedname)
+      assert.equal(tx.logs[0].args.approved, true)
+    })
+  })
+})