This post accompanies a talk on Frida me and my colleague Thomas Wimmer are giving at the FH Linux User Group in Hagenberg. GUM_API GumReplaceReturn gum_interceptor_replace (GumInterceptor * self, gpointer function_address, gpointer replacement_function, What you can do is compile your c code to an .so library that contains this function and use Frida to load it into the process. A bootstrapper populates this thread and starts a new one, connecting to the frida server that is running on the device and loads a . Interceptor. replace (sleepPtr, new NativeCallback (function (seconds) {Thread. Sign up for a free GitHub account to open an issue and contact its maintainers and the community. - malloc_hook.js. gadget: Add interaction.parameters in connect mode. To do so, we used the Interceptor.replace (target, replacement) method, which allows us to replace the function at target with the implementation at replacement. But avoid . Skip to content. Interceptor.replace(mainPtr, new NativeCallback(function (argc, argv) {console.error("[+] entry point hit - starting heap tracing"); All that was left to do was to hook the unlink() function and skip it. attach (Module. replace (1);}}); The above script replaces the return value of the function int a(), causing the instrumented test process to print "1" instead of "0". but cant't hook in specific method in android application.so For solving these issues frida provides a powerful API Interceptor. . GUM_API GumReplaceReturn gum_interceptor_replace (GumInterceptor * self, gpointer function_address, gpointer replacement_function, Interceptor. Only use Frida scripts to disable pining. As usual, let's spend a couple of word to let the folks understand what was the goal. . to print the values of the main function arguments using frida we will use frida interceptor api, the interceptor allows you to define two functions, the first one is onenter which is the handler that will be called right before the execution of the hooked function (in this case we will hook the main function) and the second one is onleave which Martin Schwaighofer's blog. Using Frida to find hooks. Asking for help, clarification, or responding to other answers. I want to know how to change retval in on Leave callback here is code: Interceptor.attach (Module.findExportByName ( "libnative-lib.so", "Java_com_targetdemo_MainA. $ cat test.js var dlopen = new NativeFunction(Module.findExportByName(null, 'dlopen'), 'pointer', ['pointer', 'int']); Interceptor.replace(dlopen, new NativeCallback . 1.2 Interceptor. This shows the real power of Frida - no patching, complicated reversing, nor difficult hours spent staring at dissassembly without end. when jni method return string value,and I use frida to hook native code. Interceptor.attach (target, callbacks) : target so target NativePointer NativePointer . frida/frida-gum. The script can be attached with the following . People following me through twitter or github already know that I recently came out with a new tool called frick, which is a Frida cli that sleep the target thread once the hook is hit giving a context with commands to play with. Intercept Swift functions and automatically parse their arguments and return values. While Frida's instrumentation core, Gum, is written in C and can be used from C, most use-cases are better off using its JavaScript bindings. As of Frida 12.5, there's a brand new JavaScript API that takes care of all the platform-specific quirks for you: const hooks = Module. Our sample application is very simple (let's call it test.c ). All gists Back to GitHub Sign in Sign up Sign in Sign up . Calls from Frida's own threads are ignored. Interceptor.replace(target, replacement[, data]): replacement target . We used Module.findExportByName (module, exp) to get the pointer to our function; null can be passed as the module in case the module name is unknown (but it will affect speed). Frida is writing code directly in process memory. We used Interceptor.revert(target): Interceptor.replace; Interceptor.flush(): attach() replace() . Have a question about this project? - malloc_hook.js. replace (Module. All gists Back to GitHub Sign in Sign up Sign in Sign up . sleep (1) return 0;}, 'int', ['uint'])); NativeCallback JavaScript replacement. . And perhaps the hook only needs to do something really simple, so most of the time is actually spent on entering and leaving the VM. Interceptor. About Me. frida-server; frida-gadget; Tools# frida CLI#. These parameters are then "reflected" into app's info under parameters.config. Frida hooks for malloc functions for further inspection. use Interceptor.attach()and only specify onEnter, and leave it empty. Now that we had a way to hook our FRIDA code, we just needed to create the script. . To do so, we used the Interceptor.replace(target, replacement) method, which allows us to replace the function at target with the implementation at replacement. 1. This post accompanies a talk on Frida me and my colleague Thomas Wimmer are giving at the FH Linux User Group in Hagenberg. frida/frida-gum. When using the resulting callback with Interceptor.replace(), func will be invoked with this bound to an object with some useful properties . Frida hooks for malloc functions for further inspection. The program is going to loop through the arguments (argv array . {retval. replace (sleepPtr, new NativeCallback (function (seconds) {Thread. findExportByName . About Me. Frida. 5 bronze badges. sleep (1) return 0;}, 'int', ['uint'])); frida-struct-pointer-pointer.js This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. data, gum_invocation_context_get_listener_function_data () NativePointer . The linked script only works for apps that are not obfuscated and that include OkHttp library. Redirecting to https://www.corellium.com/blog/android-frida-finding-hooks (308) , CModule C replacement. In this post I will show you how to use the frida Javascript API to hook the main function and print its arguments, also I will show you how to replace one of the arguments with a string allocated in memory by frida. . getExportByName (' libc.so ', ' read '), hooks. mrgreywater commented on Feb 9, 2017 edited Then you have the function and use it. - In general IMHO interception should done on network level using a proxy like mitmproxy or Fiddler, not on application level. . getExportByName (' replacement_read ')); Android. Skip to content. Fix i/macOS regression where changes related to iOS 15 support ended up breaking support for attaching to Apple system daemons. You can however use Interceptor.replace () if you need a hook that triggers regardless of caller. , CModule C replacement. 1.2 Interceptor. replace (openImpl, m. open); (Note that this and the following examples use modern JavaScript features like template literals, so they either need to be run on our V8 runtime, . $ cat test.js var dlopen = new NativeFunction(Module.findExportByName(null, 'dlopen'), 'pointer', ['pointer', 'int']); Interceptor.replace(dlopen, new NativeCallback . Interceptor.attach (target, callbacks) : target so target NativePointer NativePointer . This, specifically, is utilized by Android packers as a way to protect the contents of the underlying application. Interceptor.replace(mainPtr, new NativeCallback(function (argc, argv) {console.error("[+] entry point hit - starting heap tracing"); Frida. Frida Hook Native 4.1Hook nativeintdemo 1democnativesonative . Other examples can be seen in the wild in security products, malware, or even games deploying anti-cheat . Please be sure to answer the question.Provide details and share your research! NativeCallback JavaScript replacement. Note that the returned object is also a NativePointer, and can thus be passed to Interceptor#replace. Using the memory base address and the size of library, monitor the memory to extract useful values We can only enumerate modules from above Frida Apis . A typical Frida script (mod.js) will look something like the following: 'use strict'; Interceptor. Otherwise you'd be hooking functions and seeing calls that are made by Frida's internals, and that would be confusing. We have successfully hijacked the raw networking by injecting our own data object into memory and hooking our process with Frida, and using Interceptor to do our dirty work in manipulating the function. This may not sound like a lot, but if a function is called a million times, it's going to amount to 6 seconds of added overhead. . By Using Interceptor we can intercept calls of a Specific . Remote execution (debugging)# Proptip: Just add -H or -R if you want to use remote mode with default settings or you want to provide remote connection details. When using the resulting callback with Interceptor.replace(), func will be invoked with this bound to an object with some useful properties . Note that the returned object is also a NativePointer, and can thus be passed to Interceptor#replace. Some theoretical background on how frida works. To review, open the file in an editor that reveals hidden Unicode characters. Martin Schwaighofer's blog. Frida.version: property containing the current Frida version, . When you attach frida to a running application, frida on the background uses ptrace to hijack the thread. Frida.version: property containing the current Frida version, . Interceptor.replace (target, replacement [, data]): replacement target . Python Setup Simple as before (this is already installed with frida-tools) pip install frida Python Script First we gotta attach and create a session One technique that Android applications sometimes use to obfuscate how they work is self-hooking. We fixed so many Android-specific bugs . load (' /path/to/my-native-hooks.so '); Interceptor. Thanks for contributing an answer to Stack Overflow! If we want to change a function/replace value, (if I read it right) we have to replace the function and that's not possible with frida-trace. I am not sure if it is possible to create functions in Frida. Open binary with frida <exec> command and play with it in interactive shell session.. frida-server (remote)#