JavaScript – the MathJax display engine .

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The MathJax is an open-source JavaScript display engine for LaTeX, MathML, and AsciiMath notation that works in all modern browsers.
Just download it from official website and used like into the next example:

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<!DOCTYPE html>
<html>
<head>
<title>MathJax TeX Test Page</title>
<script type="text/x-mathjax-config">
MathJax.Hub.Config({
  tex2jax: {inlineMath: [['$','$'], ['\\(','\\)']]}
});
</script>
<script type="text/javascript" async src="MathJax-2.6-latest/MathJax.js?config=TeX-AMS_CHTML"></script>
</head>
<body>
<p>  $$
  A=\begin{pmatrix}
  a_{11} & a_{12} & \dots & a_{1n} \\
  a_{21} & a_{22} & \dots & a_{2n} \\
  \vdots & \vdots & \ddots & \vdots \\
  a_{m1} & a_{m2} & \dots & a_{mn}
  \end{pmatrix}$$</p>
<hr>
  <p>When $a \ne 0$, there are two solutions to \(ax^2 + bx + c = 0\) and they are
$$x = {-b \pm \sqrt{b^2-4ac} \over 2a}.$$</p>
<hr>
<p>$$\alpha, \beta, …, \omega$$</p>
<hr>
<p>\[ \Phi(x) = \frac{1}{\sqrt{2 \pi}}
  \int_{-\infty}^x e^{-\xi^2/2}\; d\xi \]</p>
</body>
</html>

The result of this script can be see into the next image:

JavaScript – the glMatrix.

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The glMatrix javascript is designed to perform vector and matrix operations very fast.
The official website can be found here.
What’s new in 2.0?
The glMatrix 2.0 is the result of a lot of excellent feedback from the community, and features:

  • Revamped and consistent API (not backward compatible with 1.x)
  • New functions for each type, based on request.
  • New array operations: vec(2/3/4).forEach
  • Even more optimizations!
  • A cleaner code base, broken up by type.
  • A more complete unit testing suite.

Let’s test one example with gl matrix and shaders:

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<!DOCTYPE html>
<html>
<head>
<script type="text/javascript" src="http://glmatrix.net/dist/gl-matrix-min.js"></script>
<title>Test gl matrix </title>
<script type='text/javascript'>
window.onload=function(){
var gl = document.querySelector("canvas").getContext("experimental-webgl");
 
var str = document.querySelector("#vs").textContent;
var vs = gl.createShader(gl.VERTEX_SHADER);
gl.shaderSource(vs, str);
gl.compileShader(vs);
        
var str = document.querySelector("#fs").textContent;
var fs = gl.createShader(gl.FRAGMENT_SHADER);
gl.shaderSource(fs, str);
gl.compileShader(fs);
 
var program = gl.createProgram();
gl.attachShader(program, vs);
gl.attachShader(program, fs);
gl.linkProgram(program);
gl.useProgram(program);
 
var colorLoc = gl.getAttribLocation(program, "color");
gl.enableVertexAttribArray(colorLoc);
var colorBuffer = gl.createBuffer();
gl.bindBuffer(gl.ARRAY_BUFFER, colorBuffer);
var colors = [
         1.0, 0.0, 0.0,
         0.0, 1.0, 0.0,
         0.0, 0.0, 1.0,
         1.0, 0.0, 1.0
];
gl.bufferData(gl.ARRAY_BUFFER, new Float32Array(colors), gl.STATIC_DRAW);
gl.vertexAttribPointer(colorLoc, 3, gl.FLOAT, false, 0, 0);
 
var posLoc = gl.getAttribLocation(program, "pos");
gl.enableVertexAttribArray(posLoc);
var vertexBuffer = gl.createBuffer();
gl.bindBuffer(gl.ARRAY_BUFFER, vertexBuffer);
var vertices = [
         1.0, 0.0, 0.0,
         0.0, 1.0, 0.0,
         0.0, 0.0, 1.0,
         1.0, 0.0, 1.0
];
gl.bufferData(gl.ARRAY_BUFFER, new Float32Array(vertices), gl.STATIC_DRAW);
gl.vertexAttribPointer(posLoc, 3, gl.FLOAT, false, 0, 0);
 
var indexBuffer = gl.createBuffer();
gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, indexBuffer);
var indices = [0, 1, 2, 0, 1, 3, 1, 2, 3, 0, 2, 3];
gl.bufferData(gl.ELEMENT_ARRAY_BUFFER, new Uint8Array(indices), gl.STATIC_DRAW);
 
var mmatrix = mat4.create();
mat4.scale(mmatrix, mmatrix, vec3.fromValues(0.4, 0.8, 0.7));
var mmLoc = gl.getUniformLocation(program, "MMatrix");
 
var vmatrix = mat4.create();
mat4.translate(vmatrix, vmatrix, vec3.fromValues(0, 0, -2));
var vmLoc = gl.getUniformLocation(program, "VMatrix");
gl.uniformMatrix4fv(vmLoc, false, vmatrix);
 
var pmatrix = mat4.create();
mat4.perspective(pmatrix, Math.PI/3, 2, 0.1, 100);
var pmLoc = gl.getUniformLocation(program, "GLMatrix");
gl.uniformMatrix4fv(pmLoc, false, pmatrix);
 
gl.enable(gl.DEPTH_TEST);
var render = function() {
    mat4.rotateX(mmatrix, mmatrix, 0.01);
    mat4.rotateY(mmatrix, mmatrix, 0.01);
    gl.uniformMatrix4fv(mmLoc, false, mmatrix);
    gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
    gl.drawElements(gl.TRIANGLES, indices.length, gl.UNSIGNED_BYTE, 0);
    requestAnimationFrame(render);
}
window.requestAnimationFrame = window.requestAnimationFrame
        || window.mozRequestAnimationFrame
        || window.webkitRequestAnimationFrame
        || function(cb) { setTimeout(cb, 1000/60); };
 
render();
}</script>
</head>
<body>
<canvas></canvas>
<script id="vs" type="x-shader/x-vertex">
attribute vec3 pos;
attribute vec3 color;
varying vec3 varyingColor;
uniform mat4 MMatrix;
uniform mat4 VMatrix;
uniform mat4 GLMatrix;
void main(void) {
        gl_Position = GLMatrix * VMatrix * MMatrix * vec4(pos, 1.0);
        varyingColor = color;
}
</script>
<script id="fs" type="x-shader/x-fragment">
precision mediump float;
varying vec3 varyingColor;
void main(void) {
        gl_FragColor = vec4(varyingColor, 1.0);
}
</script>
</body>
</html>

Silver the Apple’s Swift programming language on Windows.

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NOTE: Good idea , I cannot set into Windows 10 see this (https://forums.realm.io/t/errors-in-trial-settings-elements-with-visual-studio/763/2).

Now you can use the swift programming language to create applications on all platforms.
This will working in Fire (on the Mac OS) or in Visual Studio ( on Windows OS).
This is free to use.
The development team tell us about this tool:

Silver is a free implementation of Apple’s Swift programming language.
Built on over ten years of solid compiler knowledge and technology, with Silver, you can use Swift to write code directly against the .NET, Java, Android and Cocoa APIs. And you can also share a lot of non-UI code between platforms.

Now , about the full features and options the pricing is:
You can purchase the full Elements package, with support for Oxygene, C#, Swift, and Java, all four platforms, and both IDEs at $799 per user.

This is a screenshot about start a application for android using swift programming language.

Yara python module – part 002 .

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Before we start, I have to tell you that it is the continuation of an older tutorial you find here.
As you know the YARA is tool aimed at helping malware researchers to identify and classify malware samples.
The YARA tool help you to create descriptions of malware families based on textual or binary patterns.
This patterns – rules come with description consists of a set of strings and a boolean expression which determine its logic.
The YARA tool can be found on the official website.
First you need to install the python version
I used the yara-python-3.7.0.win-amd64-py3.5 version.
You need to use Python 3.5.0 version from here.
Let’s test the yara python module:

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python.exe
Python 3.5.0 (v3.5.0:374f501f4567, Sep 13 2015, 02:27:37) [MSC v.1900 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import yara
>>> from yara import *
>>> dir(yara)
['CALLBACK_ABORT', 'CALLBACK_ALL', 'CALLBACK_CONTINUE', 'CALLBACK_MATCHES', 'CALLBACK_NON_MATCHES',
'Error', 'SyntaxError', 'TimeoutError', 'WarningError', 'YARA_VERSION', 'YARA_VERSION_HEX', '__doc__',
'__file__', '__loader__', '__name__', '__package__', '__spec__', '__version__', 'compile', 'load']
>>> print(YARA_VERSION)
3.7.0
>>> print(YARA_VERSION_HEX)
198400

You can see the yara python module works well.
Let’s make a rule and test with a PDF file. This rule will tell us if the PDF come with links.
The rule is one file named detectpdflinks into this path:
C:\\BackUP\\Tools\\Python35\\detectpdflinks
The source code of this rule is:

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rule pdf_with_links {
 
meta:
  author = "Catalin George Festila"
  last_updated = "2017"
  category = "informational"
  confidence = "high"
  description = "A PDF that contains a link or external content"
 
strings:
  $pdf_test = {25 50 44 46}
  $link_anchor_tags = "<a " ascii wide nocase
  $the_uri = /\(http.+\)/ ascii wide nocase
 
condition:
  $pdf_test at 0 and (#link_anchor_tags == 1 or (#the_uri > 0 and #the_uri < 3))
 
}

Now will make the python script to use this yara rule with one pdf file:

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python.exe
Python 3.5.0 (v3.5.0:374f501f4567, Sep 13 2015, 02:27:37) [MSC v.1900 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import yara
>>>
>>> def mycallback(data):
...   print (data)
...   yara.CALLBACK_CONTINUE
...
>>> rules=yara.compile("C:\\BackUP\\Tools\\Python35\\detectpdflinks")
>>> matches = rules.match('C:\\BackUP\\PDF\\lua.pdf', callback=mycallback)
{'matches': True, 'meta': {'confidence': 'high', 'last_updated': '2017',
'author': 'Catalin George Festila', 'category': 'informational', 'description':
'A PDF that contains a link or external content'}, 'rule': 'pdf_with_links', 'strings':
[(0, '$pdf_test', b'%PDF'), (583970, '$the_uri', b'(http://www.cs.usfca.edu/galles)')],
'namespace': 'default', 'tags': []}
>>>

You can see the uri on the variable named $the_uri.