某站App签名算法解析(一)

// hook register 打印动态注册的函数地址
function hook_register(){
    // libart.so 所有导出函数表
    var symbols = Module.enumerateSymbolsSync("libart.so");
    var addr_register = null;
    for(var i = 0; i < symbols.length; i++){
        var symbol = symbols[i];
        var method_name = symbol.name;
        if(method_name.indexOf("art") >= 0){

            if(method_name.indexOf("_ZN3art3JNI15RegisterNativesEP7_JNIEnvP7_jclassPK15JNINativeMethodi") >= 0){
                addr_register = symbol.address;
            }
        }
    }

    // 开始hook
    if(addr_register){
        Interceptor.attach(addr_register, {
            onEnter: function(args){
                var methods = ptr(args[2]);
                var method_count = args[3];
                console.log("[RegisterNatives] method_count:", method_count);
                for(var i = 0; i < method_count; i++){
                    var fn_ptr = methods.add(i * Process.pointerSize * 3 + Process.pointerSize * 2).readPointer();
                    var find_module = Process.findModuleByAddress(fn_ptr);
                    if(i == 0){
                        console.log("module name", find_module.name);
                        console.log("module base", find_module.base);
                    }
                    console.log("\t method_name:", methods.add(i * Process.pointerSize * 3).readPointer().readCString(), "method_sign:", methods.add(i * Process.pointerSize * 3 + Process.pointerSize).readPointer().readCString(), "method_fnPtr:", fn_ptr, "method offset:", fn_ptr.sub(find_module.base));
                }
            }, onLeave(retval){

            }
        })
    }

}

[RegisterNatives] method_count: 0x6
module name libimagepipeline.so
module base 0x7c29c000
	 method_name: nativeAllocate method_sign: (I)J method_fnPtr: 0x7c29cc6d method offset: 0xc6d
	 method_name: nativeFree method_sign: (J)V method_fnPtr: 0x7c29ccb5 method offset: 0xcb5
	 method_name: nativeCopyToByteArray method_sign: (J[BII)V method_fnPtr: 0x7c29ccbb method offset: 0xcbb
	 method_name: nativeCopyFromByteArray method_sign: (J[BII)V method_fnPtr: 0x7c29ccd7 method offset: 0xcd7
	 method_name: nativeMemcpy method_sign: (JJI)V method_fnPtr: 0x7c29ccf3 method offset: 0xcf3
	 method_name: nativeReadByte method_sign: (J)B method_fnPtr: 0x7c29ccff method offset: 0xcff

[RegisterNatives] method_count: 0x7
module name libbili.so
module base 0x88e2b000
	 method_name: a method_sign: (Ljava/lang/String;)Ljava/lang/String; method_fnPtr: 0x88e2cc35 method offset: 0x1c35
	 method_name: ao method_sign: (Ljava/lang/String;II)Ljava/lang/String; method_fnPtr: 0x88e2cc3b method offset: 0x1c3b
	 method_name: b method_sign: (Ljava/lang/String;)Ljavax/crypto/spec/IvParameterSpec; method_fnPtr: 0x88e2cc49 method offset: 0x1c49
	 method_name: s method_sign: (Ljava/util/SortedMap;)Lcom/bilibili/nativelibrary/SignedQuery; method_fnPtr: 0x88e2cc4f method offset: 0x1c4f
	 method_name: so method_sign: (Ljava/util/SortedMap;II)Lcom/bilibili/nativelibrary/SignedQuery; method_fnPtr: 0x88e2cc55 method offset: 0x1c55
	 method_name: getCpuCount method_sign: ()I method_fnPtr: 0x88e2cc63 method offset: 0x1c63
	 method_name: getCpuId method_sign: ()I method_fnPtr: 0x88e2cc67 method offset: 0x1c67

var biliNative = Java.use("com.bilibili.nativelibrary.LibBili");

biliNative.a.implementation = function(a){
	var result = this.a(a);
    console.log("biliNative a(" + a + ") = " + result);
	return result;
}

biliNative.ao.implementation = function(a,b,c){
     var result = this.ao(a,b,c);
     console.log("biliNative ao(" + a + "," + b + "," + c + ") = " + result);
	return result;
}

biliNative.b.overload('java.lang.String').implementation = function(a){
	var result = this.b(a);
    console.log("biliNative b(" + a + ") = " + result);
	return result;
}

biliNative.s.implementation = function(map){
	var result = this.s(map);
    console.log("biliNative s(" + map + ") = " + result);
	return result;
}

biliNative.so.implementation = function(a,b,c){
     var result = this.so(a,b,c);
     console.log("biliNative so(" + a + "," + b + "," + c + ") = " + result);
	return result;
}

biliNative.s.implementation = function(HashMap){
	   var result = this.s(HashMap);

	var keys = HashMap.keySet();
	var key_set = keys.iterator();
	while (key_set.hasNext()) {
    var key = key_set.next().toString();
    var value = HashMap.get(key).toString();
    console.log(key + ": " + value);
	}

       console.log("biliNative s(" + HashMap + ") = " + result);
	   return result;
}

{'type': 'error', 'description': "TypeError: undefined not callable (property 'get' of [object Object])", 'stack': "TypeError: undefined not callable (property 'get' of [object Object])\n    at [anon] (../../../frida-gum/bindings/gumjs/duktape.c:67616)\n    at /script1.js:111\n    at je (frida/node_modules/frida-java-bridge/lib/class-factory.js:633)\n    at frida/node_modules/frida-java-bridge/lib/class-factory.js:616", 'fileName': '/script1.js', 'lineNumber': 111, 'columnNumber': 1}

biliNative.s.implementation = function(map){
	var result = this.s(map);

	var keyStr = ""
	var keys = map.keySet();
	var key_set = keys.iterator();
	while (key_set.hasNext()) {
		var key = key_set.next().toString();
		keyStr += ","+key
	}

	console.log(keyStr)
	console.log(map.values().toArray());

	console.log("biliNative s(" + map + ") = " + result);
	return result;
}