Working DNS resolution in eSIM Frida mocking

bridge-system/src/main/java/com/penumbraos/bridge_system/provider/DnsProvider.kt

@@ -1,7 +1,9 @@
 package com.penumbraos.bridge_system.provider
 
+import android.util.Log
 import com.penumbraos.bridge.IDnsProvider
 import okhttp3.Dns
+import java.net.InetAddress
 
 class DnsProvider(private val resolver: Dns) : IDnsProvider.Stub() {
     override fun lookup(hostname: String): String? {
@@ -9,7 +11,7 @@ class DnsProvider(private val resolver: Dns) : IDnsProvider.Stub() {
         return if (results.isEmpty()) {
             null
         } else {
-            results[0].hostAddress
+            (results[0] as InetAddress?)?.hostAddress
         }
     }
 }

bridge-system/src/main/java/com/penumbraos/bridge_system/util/OkHttpDnsResolver.kt

@@ -18,6 +18,12 @@ class OkHttpDnsResolver : Dns {
     private val resolver = SimpleResolver("1.1.1.1")
 
     override fun lookup(hostname: String): List<InetAddress> {
+        if (hostname.matches(Regex("^\\d+\\.\\d+\\.\\d+\\.\\d+$"))) {
+            val parts = hostname.split(".")
+            val bytes = parts.map { it.toInt().toByte() }.toByteArray()
+            return listOf(InetAddress.getByAddress(bytes))
+        }
+
         val resolvedIpString = try {
             val lookup = Lookup(hostname, Type.A)
             lookup.setResolver(resolver)

frida/src/hooks/network.ts

@@ -2,30 +2,54 @@ import { log } from "../utils/logging";
 
 let dnsProvider: any = null;
 
+// Track getDns calls to prevent infinite recursion
+let insideDnsCall = false;
+
 export const setupNetworkHooks = (): void => {
   try {
     const InetAddress = Java.use("java.net.InetAddress");
 
     const getDns = (hostname: string): string => {
-      // TODO: Something about this is incorrect
-      return dnsProvider.lookup
+      if (insideDnsCall) {
+        log(`Skipping ${hostname} fetch due to inside DNS call`);
+        return hostname;
+      }
+
+      insideDnsCall = true;
+      const result = dnsProvider.lookup
         .overload("java.lang.String")
         .call(dnsProvider, hostname);
+      insideDnsCall = false;
+      return result;
     };
 
-    const hookDnsMethod = (method: any) => {
+    const hookDnsMethod = (method: any, isList: boolean) => {
       const original = method.implementation;
       method.implementation = function (hostname: string) {
         if (dnsProvider) {
           const resolvedHostname = getDns(hostname);
+          if (isIpAddress(resolvedHostname)) {
+            log(`Creating InetAddress directly for IP ${resolvedHostname}`);
+            const parts = resolvedHostname.split(".");
+            const bytes = Java.array(
+              "byte",
+              parts.map((p) => parseInt(p))
+            );
+            const result = InetAddress.getByAddress
+              .overload("[B")
+              .call(InetAddress, bytes);
+            return isList
+              ? Java.array("java.net.InetAddress", [result])
+              : result;
+          }
           return original.call(this, resolvedHostname);
         }
         return original.call(this, hostname);
       };
     };
 
-    hookDnsMethod(InetAddress.getByName.overload("java.lang.String"));
-    hookDnsMethod(InetAddress.getAllByName.overload("java.lang.String"));
+    hookDnsMethod(InetAddress.getByName.overload("java.lang.String"), false);
+    hookDnsMethod(InetAddress.getAllByName.overload("java.lang.String"), true);
   } catch (err) {
     log(`[Frida] Network hook error: ${err}`);
   }
@@ -34,3 +58,8 @@ export const setupNetworkHooks = (): void => {
 export const setDnsProvider = (provider: any): void => {
   dnsProvider = provider;
 };
+
+const isIpAddress = (str: string): boolean => {
+  const ipv4Regex = /^(\d{1,3}\.){3}\d{1,3}$/;
+  return ipv4Regex.test(str);
+};

frida/types/index.d.ts

@@ -5,6 +5,7 @@ declare const Java: {
   ClassFactory: {
     get(loader: any): any;
   };
+  array(type: any, value: unknown[]): any;
   use(className: string): any;
   cast(obj: any, cls: any): any;
   scheduleOnMainThread(fn: () => void): void;
@@ -15,10 +16,7 @@ declare const Memory: {
 };
 
 declare const Module: {
-  getExportByName(
-    moduleName: string | null,
-    exportName: string
-  ): NativePointer;
+  getExportByName(moduleName: string | null, exportName: string): NativePointer;
 };
 
 declare const NativeFunction: new (