Merge pull request #2218 from getAlby/fix/race-condition

fix: race conditions

src/app/screens/Nostr/ConfirmSignMessage.tsx

@@ -13,7 +13,7 @@ import ScreenHeader from "~/app/components/ScreenHeader";
 import { useNavigationState } from "~/app/hooks/useNavigationState";
 import { USER_REJECTED_ERROR } from "~/common/constants";
 import msg from "~/common/lib/msg";
-import { Event } from "~/extension/ln/nostr/types";
+import { Event } from "~/extension/providers/nostr/types";
 import type { OriginData } from "~/types";
 
 function ConfirmSignMessage() {

src/extension/background-script/actions/nostr/helpers.ts

@@ -3,7 +3,7 @@ import Hex from "crypto-js/enc-hex";
 import sha256 from "crypto-js/sha256";
 import db from "~/extension/background-script/db";
 import state from "~/extension/background-script/state";
-import { Event } from "~/extension/ln/nostr/types";
+import { Event } from "~/extension/providers/nostr/types";
 
 export async function hasPermissionFor(method: string, host: string) {
   if (!host) {

src/extension/background-script/nostr/index.ts

@@ -5,7 +5,7 @@ import { AES } from "crypto-js";
 import Base64 from "crypto-js/enc-base64";
 import Hex from "crypto-js/enc-hex";
 import Utf8 from "crypto-js/enc-utf8";
-import { Event } from "~/extension/ln/nostr/types";
+import { Event } from "~/extension/providers/nostr/types";
 
 import { getEventHash, signEvent } from "../actions/nostr/helpers";
 

src/extension/content-script/onend.js

@@ -55,14 +55,15 @@ async function init() {
     if (ev.data && !ev.data.response) {
       // if an enable call railed we ignore the request to prevent spamming the user with prompts
       if (isRejected) {
-        console.error(
-          "Enable had failed. Rejecting further WebLN calls until the next reload"
-        );
+        postMessage(ev, {
+          error:
+            "webln.enable() failed (rejecting further window.webln calls until the next reload)",
+        });
         return;
       }
       // if a call is active we ignore the request
       if (callActive) {
-        console.error("WebLN call already executing");
+        postMessage(ev, { error: "window.webln call already executing" });
         return;
       }
       // limit the calls that can be made from webln
@@ -96,16 +97,7 @@ async function init() {
             isRejected = true;
           }
         }
-        window.postMessage(
-          {
-            application: "LBE",
-            response: true,
-            data: response,
-            //action: ev.data.action,
-            scope: "webln",
-          },
-          "*" // TODO use origin
-        );
+        postMessage(ev, response);
       };
       callActive = true;
       return browser.runtime
@@ -118,4 +110,17 @@ async function init() {
 
 init();
 
+function postMessage(ev, response) {
+  window.postMessage(
+    {
+      id: ev.data.id,
+      application: "LBE",
+      response: true,
+      data: response,
+      scope: "webln",
+    },
+    "*"
+  );
+}
+
 export {};

src/extension/content-script/onendnostr.js

@@ -27,7 +27,7 @@ async function init() {
     return;
   }
 
-  // message listener to listen to inpage webln calls
+  // message listener to listen to inpage nostr calls
   // those calls get passed on to the background script
   // (the inpage script can not do that directly, but only the inpage script can make webln available to the page)
   window.addEventListener("message", (ev) => {
@@ -43,14 +43,16 @@ async function init() {
     if (ev.data && !ev.data.response) {
       // if an enable call railed we ignore the request to prevent spamming the user with prompts
       if (isRejected) {
-        console.error(
-          "Enable had failed. Rejecting further WebLN calls until the next reload"
-        );
+        postMessage(ev, {
+          error:
+            "window.nostr call cancelled (rejecting further window.nostr calls until the next reload)",
+        });
         return;
       }
+
       // if a call is active we ignore the request
       if (callActive) {
-        console.error("nostr call already executing");
+        postMessage(ev, { error: "window.nostr call already executing" });
         return;
       }
 
@@ -86,15 +88,7 @@ async function init() {
           }
         }
 
-        window.postMessage(
-          {
-            application: "LBE",
-            response: true,
-            data: response,
-            scope: "nostr",
-          },
-          "*" // TODO use origin
-        );
+        postMessage(ev, response);
       };
 
       callActive = true;
@@ -106,6 +100,19 @@ async function init() {
   });
 }
 
+function postMessage(ev, response) {
+  window.postMessage(
+    {
+      id: ev.data.id,
+      application: "LBE",
+      response: true,
+      data: response,
+      scope: "nostr",
+    },
+    "*"
+  );
+}
+
 init();
 
 export {};

src/extension/inpage-script/index.js

@@ -1,6 +1,6 @@
 import { ABORT_PROMPT_ERROR, USER_REJECTED_ERROR } from "~/common/constants";
 
-import WebLNProvider from "../ln/webln";
+import WebLNProvider from "../providers/webln";
 
 if (document) {
   // window.webln is normally loaded onstart (see onstart.js)

src/extension/inpage-script/nostr.js

@@ -1,4 +1,4 @@
-import NostrProvider from "../ln/nostr";
+import NostrProvider from "../providers/nostr";
 
 if (document) {
   window.nostr = new NostrProvider();

src/extension/inpage-script/webln.js

@@ -1,5 +1,5 @@
-import WebBTCProvider from "../ln/webbtc";
-import WebLNProvider from "../ln/webln";
+import WebBTCProvider from "../providers/webbtc";
+import WebLNProvider from "../providers/webln";
 
 if (document) {
   window.webln = new WebLNProvider();

src/extension/providers/nostr/index.ts

@@ -0,0 +1,70 @@
+import { postMessage } from "../postMessage";
+import { Event } from "./types";
+
+declare global {
+  interface Window {
+    nostr: NostrProvider;
+  }
+}
+
+export default class NostrProvider {
+  nip04 = new Nip04(this);
+  enabled: boolean;
+
+  constructor() {
+    this.enabled = false;
+  }
+
+  async enable() {
+    if (this.enabled) {
+      return { enabled: true };
+    }
+    return await this.execute("enable");
+  }
+
+  async getPublicKey() {
+    await this.enable();
+    return await this.execute("getPublicKeyOrPrompt");
+  }
+
+  async signEvent(event: Event) {
+    await this.enable();
+    return this.execute("signEventOrPrompt", { event });
+  }
+
+  async signSchnorr(sigHash: string) {
+    await this.enable();
+    return this.execute("signSchnorrOrPrompt", { sigHash });
+  }
+
+  async getRelays() {
+    await this.enable();
+    return this.execute("getRelays");
+  }
+
+  // NOTE: new call `action`s must be specified also in the content script
+  execute(
+    action: string,
+    args?: Record<string, unknown>
+  ): Promise<Record<string, unknown>> {
+    return postMessage("nostr", action, args);
+  }
+}
+
+class Nip04 {
+  provider: NostrProvider;
+
+  constructor(provider: NostrProvider) {
+    this.provider = provider;
+  }
+
+  async encrypt(peer: string, plaintext: string) {
+    await this.provider.enable();
+    return this.provider.execute("encryptOrPrompt", { peer, plaintext });
+  }
+
+  async decrypt(peer: string, ciphertext: string) {
+    await this.provider.enable();
+    return this.provider.execute("decryptOrPrompt", { peer, ciphertext });
+  }
+}

src/extension/providers/postMessage.ts

@@ -0,0 +1,51 @@
+export function postMessage<T>(
+  scope: string,
+  action: string,
+  args: T | undefined
+): Promise<T> {
+  return new Promise((resolve, reject) => {
+    const id = Math.random().toString().slice(4);
+
+    // post the request to the content script. from there it gets passed to the background script and back
+    // in page script can not directly connect to the background script
+    window.postMessage(
+      {
+        id: id,
+        application: "LBE",
+        prompt: true,
+        action: `${scope}/${action}`,
+        scope: scope,
+        args,
+      },
+      "*" // TODO use origin
+    );
+
+    function handleWindowMessage(messageEvent: MessageEvent) {
+      // check if it is a relevant message
+      // there are some other events happening
+      if (
+        !messageEvent.data ||
+        !messageEvent.data.response ||
+        messageEvent.data.application !== "LBE" ||
+        messageEvent.data.scope !== scope ||
+        messageEvent.data.id !== id
+      ) {
+        return;
+      }
+
+      if (messageEvent.data.data.error) {
+        reject(new Error(messageEvent.data.data.error));
+      } else {
+        // 1. data: the message data
+        // 2. data: the data passed as data to the message
+        // 3. data: the actual response data
+        resolve(messageEvent.data.data.data);
+      }
+
+      // For some reason must happen only at the end of this function
+      window.removeEventListener("message", handleWindowMessage);
+    }
+
+    window.addEventListener("message", handleWindowMessage);
+  });
+}