hook_art.js

/*
GetFieldID is at  0xe39b87c5 _ZN3art3JNI10GetFieldIDEP7_JNIEnvP7_jclassPKcS6_
GetMethodID is at  0xe39a1a19 _ZN3art3JNI11GetMethodIDEP7_JNIEnvP7_jclassPKcS6_
NewStringUTF is at  0xe39cff25 _ZN3art3JNI12NewStringUTFEP7_JNIEnvPKc
RegisterNatives is at  0xe39e08fd _ZN3art3JNI15RegisterNativesEP7_JNIEnvP7_jclassPK15JNINativeMethodi
GetStaticFieldID is at  0xe39c9635 _ZN3art3JNI16GetStaticFieldIDEP7_JNIEnvP7_jclassPKcS6_
GetStaticMethodID is at  0xe39be0ed _ZN3art3JNI17GetStaticMethodIDEP7_JNIEnvP7_jclassPKcS6_
GetStringUTFChars is at  0xe39d06e5 _ZN3art3JNI17GetStringUTFCharsEP7_JNIEnvP8_jstringPh
FindClass is at  0xe399ae5d _ZN3art3JNI9FindClassEP7_JNIEnvPKc
*/  

function hook_libart() {
    var symbols = Module.enumerateSymbolsSync("libart.so");
    var addrGetStringUTFChars = null;
    var addrNewStringUTF = null;
    var addrFindClass = null;
    var addrGetMethodID = null;
    var addrGetStaticMethodID = null;
    var addrGetFieldID = null;
    var addrGetStaticFieldID = null;
    var addrRegisterNatives = null;
    for (var i = 0; i < symbols.length; i++) {
        var symbol = symbols[i];
        if (symbol.name.indexOf("art") >= 0 &&
            symbol.name.indexOf("JNI") >= 0 &&
            symbol.name.indexOf("CheckJNI") < 0
        ) {
            if (symbol.name.indexOf("GetStringUTFChars") >= 0) {
                addrGetStringUTFChars = symbol.address;
                console.log("GetStringUTFChars is at ", symbol.address, symbol.name);
            } else if (symbol.name.indexOf("NewStringUTF") >= 0) {
                addrNewStringUTF = symbol.address;
                console.log("NewStringUTF is at ", symbol.address, symbol.name);
            } else if (symbol.name.indexOf("FindClass") >= 0) {
                addrFindClass = symbol.address;
                console.log("FindClass is at ", symbol.address, symbol.name);
            } else if (symbol.name.indexOf("GetMethodID") >= 0) {
                addrGetMethodID = symbol.address;
                console.log("GetMethodID is at ", symbol.address, symbol.name);
            } else if (symbol.name.indexOf("GetStaticMethodID") >= 0) {
                addrGetStaticMethodID = symbol.address;
                console.log("GetStaticMethodID is at ", symbol.address, symbol.name);
            } else if (symbol.name.indexOf("GetFieldID") >= 0) {
                addrGetFieldID = symbol.address;
                console.log("GetFieldID is at ", symbol.address, symbol.name);
            } else if (symbol.name.indexOf("GetStaticFieldID") >= 0) {
                addrGetStaticFieldID = symbol.address;
                console.log("GetStaticFieldID is at ", symbol.address, symbol.name);
            } else if (symbol.name.indexOf("RegisterNatives") >= 0) {
                addrRegisterNatives = symbol.address;
                console.log("RegisterNatives is at ", symbol.address, symbol.name);
            }
        }
    }

    if (addrGetStringUTFChars != null) {
        Interceptor.attach(addrGetStringUTFChars, {
            onEnter: function (args) {},
            onLeave: function (retval) {
                if (retval != null) {
                    var bytes = Memory.readCString(retval);
                    console.log("[GetStringUTFChars] result:" + bytes);
                }
            }
        });
    }
    if (addrNewStringUTF != null) {
        Interceptor.attach(addrNewStringUTF, {
            onEnter: function (args) {
                if (args[1] != null) {
                    var string = Memory.readCString(args[1]);
                    console.log("[NewStringUTF] bytes:" + string);
                }
            },
            onLeave: function (retval) {}
        });
    }
    if (addrFindClass != null) {
        Interceptor.attach(addrFindClass, {
            onEnter: function (args) {
                if (args[1] != null) {
                    var name = Memory.readCString(args[1]);
                    console.log("[FindClass] name:" + name);
                }
            },
            onLeave: function (retval) {}
        });
    }
    if (addrGetMethodID != null) {
        Interceptor.attach(addrGetMethodID, {
            onEnter: function (args) {
                if (args[2] != null) {
                    var name = Memory.readCString(args[2]);
                    if (args[3] != null) {
                        var sig = Memory.readCString(args[3]);
                        console.log("[GetMethodID] name:" + name + ", sig:" + sig);
                    } else {
                        console.log("[GetMethodID] name:" + name);
                    }

                }
            },
            onLeave: function (retval) {}
        });
    }
    if (addrGetStaticMethodID != null) {
        Interceptor.attach(addrGetStaticMethodID, {
            onEnter: function (args) {
                if (args[2] != null) {
                    var name = Memory.readCString(args[2]);
                    if (args[3] != null) {
                        var sig = Memory.readCString(args[3]);
                        console.log("[GetStaticMethodID] name:" + name + ", sig:" + sig);
                    } else {
                        console.log("[GetStaticMethodID] name:" + name);
                    }

                }
            },
            onLeave: function (retval) {}
        });
    }
    if (addrGetFieldID != null) {
        Interceptor.attach(addrGetFieldID, {
            onEnter: function (args) {
                if (args[2] != null) {
                    var name = Memory.readCString(args[2]);
                    if (args[3] != null) {
                        var sig = Memory.readCString(args[3]);
                        console.log("[GetFieldID] name:" + name + ", sig:" + sig);
                    } else {
                        console.log("[GetFieldID] name:" + name);
                    }

                }
            },
            onLeave: function (retval) {}
        });
    }
    if (addrGetStaticFieldID != null) {
        Interceptor.attach(addrGetStaticFieldID, {
            onEnter: function (args) {
                if (args[2] != null) {
                    var name = Memory.readCString(args[2]);
                    if (args[3] != null) {
                        var sig = Memory.readCString(args[3]);
                        console.log("[GetStaticFieldID] name:" + name + ", sig:" + sig);
                    } else {
                        console.log("[GetStaticFieldID] name:" + name);
                    }

                }
            },
            onLeave: function (retval) {}
        });
    }

    if (addrRegisterNatives != null) {
        Interceptor.attach(addrRegisterNatives, {
            onEnter: function (args) {
                console.log("[RegisterNatives] method_count:", args[3]);
                var env = args[0];
                var java_class = args[1];
                var class_name = Java.vm.tryGetEnv().getClassName(java_class);

                var methods_ptr = ptr(args[2]);

                var method_count = parseInt(args[3]);
                for (var i = 0; i < method_count; i++) {
                    var name_ptr = Memory.readPointer(methods_ptr.add(i * Process.pointerSize * 3));
                    var sig_ptr = Memory.readPointer(methods_ptr.add(i * Process.pointerSize * 3 + Process.pointerSize));
                    var fnPtr_ptr = Memory.readPointer(methods_ptr.add(i * Process.pointerSize * 3 + Process.pointerSize * 2));

                    var name = Memory.readCString(name_ptr);
                    var sig = Memory.readCString(sig_ptr);
                    var find_module = Process.findModuleByAddress(fnPtr_ptr);
                    console.log("[RegisterNatives] java_class:", class_name, "name:", name, "sig:", sig, "fnPtr:", fnPtr_ptr, "module_name:", find_module.name, "module_base:", find_module.base, "offset:", ptr(fnPtr_ptr).sub(find_module.base));

                }
            },
            onLeave: function (retval) {}
        });
    }
}

setImmediate(hook_libart);