WebSocket API for CDS

ts/textsecure/CDSSocketManager.ts

@@ -0,0 +1,82 @@
+// Copyright 2021 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import ProxyAgent from 'proxy-agent';
+import { HsmEnclaveClient, PublicKey } from '@signalapp/signal-client';
+import type { connection as WebSocket } from 'websocket';
+
+import * as Bytes from '../Bytes';
+import type { AbortableProcess } from '../util/AbortableProcess';
+import * as log from '../logging/log';
+import type { UUIDStringType } from '../types/UUID';
+import { CDSSocket } from './CDSSocket';
+import { connect as connectWebSocket } from './WebSocket';
+
+export type CDSSocketManagerOptionsType = Readonly<{
+  url: string;
+  publicKey: string;
+  codeHash: string;
+  certificateAuthority: string;
+  proxyUrl?: string;
+  version: string;
+}>;
+
+export class CDSSocketManager {
+  private readonly publicKey: PublicKey;
+
+  private readonly codeHash: Buffer;
+
+  private readonly proxyAgent?: ReturnType<typeof ProxyAgent>;
+
+  constructor(private readonly options: CDSSocketManagerOptionsType) {
+    this.publicKey = PublicKey.deserialize(
+      Buffer.from(Bytes.fromHex(options.publicKey))
+    );
+    this.codeHash = Buffer.from(Bytes.fromHex(options.codeHash));
+    if (options.proxyUrl) {
+      this.proxyAgent = new ProxyAgent(options.proxyUrl);
+    }
+  }
+
+  public async request({
+    e164s,
+    timeout,
+  }: {
+    e164s: ReadonlyArray<string>;
+    timeout?: number;
+  }): Promise<ReadonlyArray<UUIDStringType | null>> {
+    log.info('CDSSocketManager: connecting socket');
+    const socket = await this.connect().getResult();
+    log.info('CDSSocketManager: connected socket');
+
+    try {
+      return await socket.request({ e164s, timeout });
+    } finally {
+      log.info('CDSSocketManager: closing socket');
+      socket.close(3000, 'Normal');
+    }
+  }
+
+  private connect(): AbortableProcess<CDSSocket> {
+    const enclaveClient = HsmEnclaveClient.new(this.publicKey, [this.codeHash]);
+
+    const {
+      publicKey: publicKeyHex,
+      codeHash: codeHashHex,
+      version,
+    } = this.options;
+
+    const url = `${this.options.url}/discovery/${publicKeyHex}/${codeHashHex}`;
+
+    return connectWebSocket<CDSSocket>({
+      url,
+      version,
+      proxyAgent: this.proxyAgent,
+      certificateAuthority: this.options.certificateAuthority,
+
+      createResource: (socket: WebSocket): CDSSocket => {
+        return new CDSSocket(socket, enclaveClient);
+      },
+    });
+  }
+}