jnitrace engine

محرك Jnitrace

المحرك المستخدم من قبل Jnitrace لاعتراض مكالمات API JNI.

jnitrace-engine هو المشروع الذي تستخدمه Jnitrace لاعتراض وتهدر مكالمات API JNI. لقد تم تعريضه كمشروع منفصل للسماح لمطوري وحدة Frida باستخدام نفس المحرك لاعتراض وتعديل مكالمات API JNI التي تم إجراؤها بواسطة تطبيقات Android.

تثبيت:

أسهل طريقة للركض مع jnitrace-engine هي استخدام NPM:

npm install jnitrace-engine

استخدام بسيط:

يحاول jnitrace-engine عكس أكبر قدر ممكن من واجهة برمجة تطبيقات Frida. يوفر JNIInterceptor واجهة برمجة تطبيقات لإرفاق مكالمات JNI API بطريقة مشابهة للغاية مع Interceptor Frida. تتمثل الفكرة في جعل استخدام المكتبة سهلة الاستخدام لأولئك على دراية بالفعل بـ Frida. الأمثلة أدناه هي JavaScript ولكن الوحدة النمطية تدعم أيضًا TypeScript.

 import { JNIInterceptor } from "jnitrace-engine" ;

// Attach to the JNI FindClass method
JNIInterceptor . attach ( "FindClass" , {
    onEnter ( args ) {
        // called whenever the FindClass is about to be called
        console . log ( "FindClass method called" ) ;
        this . className = Memory . readCString ( args [ 1 ] ) ;
    } ,
    onLeave ( retval ) {
        // called whenever the FindClass method has finished executing
        console . log ( "tLoading Class:" , this . className ) ;
        console . log ( "tClass ID:" , retval . get ( ) ) ;
    }
} ) ; 

الاستخدام المتقدم:

 import { JNIInterceptor } from "jnitrace-engine" ;
import { JNILibraryWatcher } from "jnitrace-engine" ;
import { JNINativeReturnValue } from "jnitrace-engine" ;
import { ConfigBuilder } from "jnitrace-engine" ;

// configure the jnitrace-engine to limit what libraries to traces
const builder : ConfigBuilder = new ConfigBuilder ( ) ;

builder . libraries = [ "libnative-lib.so" ] ; // set a list of libraries to track
builder . backtrace = "fuzzy" ; // choose the backtracer type to use [accurate/fuzzy/none]
builder . includeExports = [ "Java_com_nativetest_MainActivity_stringFromJNI" ] ; // provide a list of library exports to track
builder . excludeExports = [ ] ; // provide a list of library exports to ignore
builder . env = true ; // set whether to trace the JNIEnv struct or ignore all of it
builder . vm = false ; // set whether to trace the JavaVM struct or ignore all of it

const config = builder . build ( ) ; //initialise the config - this makes it available to the engine

// An additional callback that can be used for listening to new libraries being loaded by an application
// Note this callback will be called for all libraries, not just the ones in the config
// libraries list
JNILibraryWatcher . setCallback ( {
    onLoaded ( path : string ) {
        console . log ( "Library Loaded " + path ) ;
        console . log ( "Currently Traced Libraries" , JSON . stringify ( config . libraries ) ) ;
    }
} ) ;

const findClassIntercept = JNIInterceptor . attach ( "FindClass" , {
    onEnter ( args : NativeArgumentValue [ ] ) {
        console . log ( "Find Class called" ) ;
        args [ 1 ] = NULL ; // Change the arguments to the FindClass function
        console . log ( "ThreadId" , this . threadId ) ;
        console . log ( "Address of FindClass method" , this . jniAddress ) ;
        this . backtrace . forEach ( ( element : NativePointer ) => {
            console . log ( "backtrace" , element ) ;
        } ) ;
    } ,
    onLeave ( retval : JNINativeReturnValue ) {
        // Change the retval to be returned to the caller of FindClass
        retval . replace ( NULL ) ;
        // Detach all JNI intercepts
        JNIInterceptor . detatchAll ( ) ;
    }
} ) ;

JNIInterceptor . attach ( "CallDoubleMethodV" , {
    onLeave ( retval : JNINativeReturnValue ) {
        // Log the method params of the Java method the JNI API is calling.
        // this.javaMethod will only exist if a Java method has been called.
        console . log ( "Java Method Args" , JSON . stringify ( this . javaMethod . params ) ) ;
        // Detach from the FindClass intercept
        findClassIntercept . detach ( ) ;
    }
} ) ;