ENSIP-10 Reverse Resolution

src.ts/_tests/test-providers-ccip.ts

@@ -179,4 +179,16 @@ describe("Test CCIP execution", function() {
         const result = await provider.call(tx);
         verify(address, calldata, result);
     });
+
+    // it("query a ensip-10 reverse registrar that's offchain", async function() {
+    //     this.timeout(60000);
+
+    //     const provider = connect("goerli");
+
+    //     // this accounts primary has an offchain reverse resolver
+    //     const address = '0xEB4200f750335eFb67E726485445d302D64B1c8A';
+    //     const name = await provider.lookupAddress(address);
+    //     console.log(name);
+    // });
+
 })

src.ts/providers/abstract-provider.ts

@@ -15,14 +15,11 @@
 //   of Signer/ENS name to address so we can sync respond to listenerCount.
 
 import { getAddress, resolveAddress } from "../address/index.js";
-import { ZeroAddress } from "../constants/index.js";
-import { Contract } from "../contract/index.js";
-import { namehash } from "../hash/index.js";
 import { Transaction } from "../transaction/index.js";
 import {
     concat, dataLength, dataSlice, hexlify, isHexString,
     getBigInt, getBytes, getNumber,
-    isCallException, isError, makeError, assert, assertArgument,
+    isCallException, makeError, assert, assertArgument,
     FetchRequest,
     toBeArray, toQuantity,
     defineProperties, EventPayload, resolveProperties,
@@ -1196,41 +1193,18 @@ export class AbstractProvider implements Provider {
 
     async lookupAddress(address: string): Promise<null | string> {
         address = getAddress(address);
-        const node = namehash(address.substring(2).toLowerCase() + ".addr.reverse");
-
-        try {
-
-            const ensAddr = await EnsResolver.getEnsAddress(this);
-            const ensContract = new Contract(ensAddr, [
-                "function resolver(bytes32) view returns (address)"
-            ], this);
-
-            const resolver = await ensContract.resolver(node);
-            if (resolver == null || resolver === ZeroAddress) { return null; }
-
-            const resolverContract = new Contract(resolver, [
-                "function name(bytes32) view returns (string)"
-            ], this);
-            const name = await resolverContract.name(node);
-
-            // Failed forward resolution
-            const check = await this.resolveName(name);
-            if (check !== address) { return null; }
-
-            return name;
-
-        } catch (error) {
-            // No data was returned from the resolver
-            if (isError(error, "BAD_DATA") && error.value === "0x") {
-                return null;
+        const resolver = await this.getResolver(address.substring(2).toLowerCase() + ".addr.reverse");
+        if (resolver) {
+            const name = await resolver.getName();
+            if (name) { // possible optimization: name.includes('.')
+                const expect = await this.resolveName(name);
+                // check roundtrip
+                assert(address === expect, "address->name->address mismatch", "VALUE_MISMATCH", {lhs: address, rhs: expect});
+                return name;
             }
-
-            // Something reerted
-            if (isError(error, "CALL_EXCEPTION")) { return null; }
-
-            throw error;
         }
-
+        // i think ALL errors should propagate out as reverse names are a critical piece 
+        // of ENS infrastructure and saying a primary is null should be a true-positive
         return null;
     }
 

src.ts/providers/ens-resolver.ts

@@ -188,6 +188,7 @@ export class EnsResolver {
             "function addr(bytes32, uint) view returns (bytes)",
             "function text(bytes32, string) view returns (string)",
             "function contenthash(bytes32) view returns (bytes)",
+            "function name(bytes32) view returns (string)",
         ], provider);
 
     }
@@ -313,6 +314,14 @@ export class EnsResolver {
         });
     }
 
+    /**
+     *  Resolves to the ENSIP-3 name record for %%key%%, or ``null``
+     *  if unconfigured.
+     */
+    async getName(): Promise<null | string> {
+        return this.#fetch("name(bytes32)");
+    }
+
     /**
      *  Resolves to the EIP-634 text record for %%key%%, or ``null``
      *  if unconfigured.

src.ts/utils/errors.ts

@@ -574,6 +574,20 @@ export interface ActionRejectedError extends EthersError<"ACTION_REJECTED"> {
     reason: "expired" | "rejected" | "pending"
 }
 
+/**
+ *  This Error indicates `lhs` != `rhs`.
+ */
+export interface ValueMismatchError extends EthersError<"VALUE_MISMATCH"> {
+    /**
+     *  The left-hand side.
+     */
+    lhs: any,
+    /**
+     *  The right-hand side.
+     */
+    rhs: any
+}
+
 // Coding; converts an ErrorCode its Typed Error
 
 /**
@@ -608,6 +622,7 @@ export type CodedEthersError<T> =
     T extends "UNCONFIGURED_NAME" ? UnconfiguredNameError:
 
     T extends "ACTION_REJECTED" ? ActionRejectedError:
+	T extends "VALUE_MISMATCH" ? ValueMismatchError:
 
     never;