Fix app killing on Frida script failures, to ensure clean shutdown

Previously we killed without resume, which doesn't actually work in all
(some?) cases. This does now seem to reliably work everywhere.

Author: pimterry

src/interceptors/frida/frida-android-integration.ts

@@ -16,6 +16,7 @@ import {
     FRIDA_DEFAULT_PORT,
     FRIDA_VERSION,
     FridaHost,
+    killProcess,
     launchScript,
     testAndSelectProxyAddress
 } from './frida-integration';
@@ -210,7 +211,7 @@ export async function interceptAndroidFridaTarget(
         console.log(`Frida Android interception started: ${appId} on ${hostId} forwarding to ${proxyIp}:${proxyPort}`);
     } catch (e) {
         // If anything goes wrong, just make sure we shut down the app again
-        await session.kill();
+        await killProcess(session).catch(console.log)
         throw e;
     }
 }

src/interceptors/frida/frida-integration.ts

@@ -1,5 +1,5 @@
 import * as FridaJs from 'frida-js';
-import { CustomError } from '@httptoolkit/util';
+import { CustomError, delay } from '@httptoolkit/util';
 
 import { getReachableInterfaces } from '../../util/network';
 import { buildIpTestScript } from './frida-scripts';
@@ -55,6 +55,15 @@ class FridaProxyError extends CustomError {
     }
 }
 
+export async function killProcess(session: FridaJs.FridaAgentSession) {
+    // We have to resume and then wait briefly before we can kill:
+    await session.resume()
+        .then(() => delay(100)) // Even 0 seems to work - but let's be safe
+        .catch(() => {});
+
+    await session.kill();
+}
+
 export async function testAndSelectProxyAddress(
     session: FridaJs.FridaAgentSession,
     proxyPort: number,

src/interceptors/frida/frida-ios-integration.ts

@@ -6,6 +6,7 @@ import { buildIosFridaScript } from './frida-scripts';
 import {
     FRIDA_DEFAULT_PORT,
     FridaHost,
+    killProcess,
     launchScript,
     testAndSelectProxyAddress
 } from './frida-integration';
@@ -127,7 +128,7 @@ export async function interceptIosFridaTarget(
         console.log(`Frida iOS interception started: ${appId} on ${hostId} forwarding to ${proxyIp}:${proxyPort}`);
     } catch (e) {
         // If anything goes wrong, just make sure we shut down the app again
-        await session.kill();
+        await killProcess(session).catch(console.log);
         throw e;
     }
 }