fix: Multiaddr from fields function

src/lib/enr/enr.ts

@@ -347,7 +347,7 @@ export class ENR extends Map<ENRKey, ENRValue> {
     const isIpv6 = protocol.endsWith("6");
     const ipVal = this.get(isIpv6 ? "ip6" : "ip");
     if (!ipVal) {
-      return undefined;
+      return;
     }
 
     const isUdp = protocol.startsWith("udp");
@@ -367,7 +367,12 @@ export class ENR extends Map<ENRKey, ENRValue> {
       return;
     }
 
-    return mulitaddrFromFields(isIpv6, protoName, ipVal, protoVal);
+    return mulitaddrFromFields(
+      isIpv6 ? "ip6" : "ip4",
+      protoName,
+      ipVal,
+      protoVal
+    );
   }
 
   setLocationMultiaddr(multiaddr: Multiaddr): void {

src/lib/enr/multiaddr_from_fields.spec.ts

@@ -8,8 +8,17 @@ describe("Multiaddr from fields", () => {
     const ipBytes = convertToBytes("ip4", "1.2.3.4");
     const portBytes = convertToBytes("tcp", "3333");
 
-    const ma = mulitaddrFromFields(false, "tcp", ipBytes, portBytes);
+    const ma = mulitaddrFromFields("ip4", "tcp", ipBytes, portBytes);
 
     expect(ma.toString()).to.eq("/ip4/1.2.3.4/tcp/3333");
   });
+
+  it("udp ip6 address", function () {
+    const ipBytes = convertToBytes("ip6", "2345:425:2ca1::5673:23b5");
+    const portBytes = convertToBytes("udp", "1111");
+
+    const ma = mulitaddrFromFields("ip6", "udp", ipBytes, portBytes);
+
+    expect(ma.toString()).to.eq("/ip6/2345:425:2ca1::5673:23b5/udp/1111");
+  });
 });

src/lib/enr/multiaddr_from_fields.ts

@@ -1,17 +1,21 @@
 import { Multiaddr } from "@multiformats/multiaddr";
+import { convertToString } from "@multiformats/multiaddr/convert";
 
 export function mulitaddrFromFields(
-  isIpv6: boolean,
+  ipFamily: string,
   protocol: string,
   ipBytes: Uint8Array,
-  portBytes: Uint8Array
+  protocolBytes: Uint8Array
 ): Multiaddr {
-  const familyStr = isIpv6 ? "ip6" : "ip4";
-  let ma = new Multiaddr("/" + familyStr);
+  let ma = new Multiaddr(
+    "/" + ipFamily + "/" + convertToString(ipFamily, ipBytes)
+  );
 
-  ma = ma.encapsulate(new Multiaddr(ipBytes));
-  ma = ma.encapsulate(new Multiaddr("/" + protocol));
-  ma = ma.encapsulate(portBytes);
+  ma = ma.encapsulate(
+    new Multiaddr(
+      "/" + protocol + "/" + convertToString(protocol, protocolBytes)
+    )
+  );
 
   return ma;
 }