Step by Step solution about How to resolve the algorithm Break OO privacy step by step in the PHP programming language

Sourcecode 1

1. The first snippet of code creates a class called SimpleClass with a private property answer set to the string "hello\"world\nforever :)".
2. It then creates an instance of the SimpleClass class and uses ob_start() to start buffering output.
3. It then uses var_export() to export the class to a string, but removes the __set_state() method from the result using preg_replace().
4. It then uses eval() to evaluate the string and create a new instance of the SimpleClass class with the same private property value as the original class.
5. Finally, it prints the value of the answer property of the new class instance.

Sourcecode 2

1. The second snippet of code creates a class called SimpleClass with a private property answer set to the integer 42.
2. It then creates an instance of the SimpleClass class and uses (array) to convert it to an array.
3. It then prints the value of the answer property of the array using the array syntax ["\0SimpleClass\0answer"].

Sourcecode 3

1. The third snippet of code creates a class called fragile with a private property foo set to the string 'bar'.
2. It then creates an instance of the fragile class and uses ReflectionObject() to create a reflection object for the class.
3. It then uses getProperty() to get the reflection property for the foo property and uses setAccessible(true) to make the property accessible.
4. It then uses getValue() to get the value of the foo property and prints it.
5. It then uses setValue() to set the value of the foo property to the string 'haxxorz!' and prints the new value.
6. Finally, it prints the fragile class instance to show that the value of the foo property has been changed.

<?php
class SimpleClass {
    private $answer = "hello\"world\nforever :)";
}
 
$class = new SimpleClass;
ob_start();
 
// var_export() expects class to contain __set_state() method which would import
// data from array. But let's ignore this and remove from result the method which
// sets state and just leave data which can be used everywhere... 
var_export($class);
$class_content = ob_get_clean();
 
$class_content = preg_replace('"^SimpleClass::__set_state\("', 'return ', $class_content);
$class_content = preg_replace('"\)$"', ';', $class_content);

$new_class = eval($class_content);
echo $new_class['answer'];


<?php
class SimpleClass {
    private $answer = 42;
}

$class = new SimpleClass;
$classvars = (array)$class;
echo $classvars["\0SimpleClass\0answer"];


<?php
class fragile {
    private $foo = 'bar';
}
$fragile = new fragile;
$ro = new ReflectionObject($fragile);
$rp = $ro->getProperty('foo');
$rp->setAccessible(true);
var_dump($rp->getValue($fragile));
$rp->setValue($fragile, 'haxxorz!');
var_dump($rp->getValue($fragile));
var_dump($fragile);