Frida Intro

hello.c

#include <stdio.h>
#include <unistd.h>

void
f (int n)
{
  printf ("Number: %d\n", n);
}

int
main ()
{
  int i = 0;

  printf ("f() is at %p\n", f);

  while (1)
  {
    f (i++);
    sleep (1);
  }
}

modify.js

'use strict';

const co = require('co');
const frida = require('frida');

let session, script;
co(function *() {
  session = yield frida.attach('hello');
  script = yield session.createScript('(' + agent.toString() + ').call(this);');
  yield script.load();
});

function agent() {
  'use strict';

  Interceptor.attach(ptr('0x106a81ec0'), {
    onEnter: function (args) {
      args[0] = ptr("1337");
    }
  });
}