Implement watchpoints

[trufae]

• change memory protections with Memory.protect()
• hook the setExceptionHandler() and catch if it's R,W,X and the address matches.

Ole André Vadla Ravnås, [19 Feb 2017 01:46]:

(on top of Memory.protect() and Process.setExceptionHandler())

only part I don't like is that Process.setExceptionHandler() is just a single handler obviously
so it would be nice to have API that has a chain of handlers
where they're called in order

[ghostkkk]

Hi~

I'd like to ask you a question.

r2Frida has no watch function.

so I tried the above method.

Memroy.protect made the write part of a specific memory area read only.

a moment to write, Process.setExceptionHandler does not work. Attated Process Close immediately.

Perhaps...Process.setExceptionHandler function is not implemented yet.

my test version.
server : frida-server-12.2.5-android-x86
r2frida : v2.9.0

// test sample
function fnExcetion(v){
		console.log('Enter:');
		return true;
}

// register ExceptionHandler 
Process.setExceptionHandler(fnExcetion);

// Variable Address in program
address = "0xb2dd5040";
Memory.protect(ptr(address), 4, 'r--');

What's wrong?
If you tested it, Can I see a sample code or Test version?

[trufae]

closing as dup for #496 and may be helpful to keep it here for our future selfs when implementing it