"Magic Zoom V3 image magnifier effect" script analysis

Jul 4 posted in Web (RSS), comments.

Advertisements

Recent want to try an image magnifier effect, on-line (domestic) reference may be called up to "Magic Zoom" of jQuery plugins. The plug is a commercial software, trial version to enlarge box at the bottom or top of the line prompt with the prompt to upgrade to full version (Please upgrade to full version of Magic Zoom). In fact, the demo function is complete, but much more prompt this line only.

Internet search, I have not found this component was more comprehensive analysis, only to find some way to remove the use of violence, the line message. Specifically, we can go to this address (http://www.5icool.org/a/201004/379.html) see, I saved Ctrl + C And Ctrl + V to operate.

This component has no one to analyze (or is not of them), it brought back my interest to see how strong the JS security in the end. So there will be a process and the analysis of this article.

First, download the components from the official website of the DEMO version, open magiczoom.js, search on "Please upgrade to full version of Magic Zoom" phrase in the key words, not found. This I expected, if the words do not look at Tibet, it is also what anti-theft ah.

Look at the script, sets out an eval, which in general, eval the middle of things are sure to have a normal after treatment JS script, so long as to keep the script Jinong out period, basic even if successful. According to this thinking, to eval temporarily removed, the remaining things, there is a large string, the piece of string or removed, what remains is not much, sort format, as follows:

function(p,a,c,k,e,d){
        e=function(c){
                return(c<a?'':e(parseInt(c/a)))+((c=c%a)>35?String.fromCharCode(c+29):c.toString(36));
        };
        if(!''.replace(/^/,String)){
                while(c--){
                        d[e(c)]=k[c]||e(c);
                }
                k=[
                        function(e){
                                return d[e]
                        }
                ];
                e=function(){
                        return'\\w+';
                }
                c=1;
        };
        while(c--){
                if(k[c]){
                        p=p.replace(new RegExp('\\b'+e(c)+'\\b','g'),k[c]);
                }
        }
        return p;
}( STR1, 62,639, STR2.split('|'),0,{});

Of which: STR1, STR2 is drawn to the location of the two long strings.

Analysis of this code, it is more clear, define an anonymous function, and then passed six parameters of the Executive, to get a result, the final look by the eval method to execute.

Next, I just write the code, this function returns the resulting output can, I write in EditPlus an HTML page, to the implementation of the above function, the resulting output to a textarea:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<html>
 <head>
  <title> New Document </title>
  <meta name="Generator" content="EditPlus">
  <meta name="Author" content="">
  <meta name="Keywords" content="">
  <meta name="Description" content="">
<script language="JavaScript">
<!--

var s1 = < Omit  >;

var s2 = < Omit  >;


function decode(p,a,c,k,e,d){
        e=function(c){
                return(c<a?'':e(parseInt(c/a)))+((c=c%a)>35?String.fromCharCode(c+29):c.toString(36));
        };
        if(!''.replace(/^/,String)){
                while(c--){
                        d[e(c)]=k[c]||e(c);
                }
                k=[
                        function(e){
                                return d[e];
                        }
                ];
                e=function(){
                        return'\\w+';
                };
                c=1;
        };
        while(c--){
                if(k[c]){
                        p=p.replace(new RegExp('\\b'+e(c)+'\\b','g'),k[c]);
                }
        }
        return p;
}

window.onload=function(){
  var srcTxt = decode(s1,62,650, s2.split('|'),0,{});
        document.all.src.value = srcTxt;
}

//-->
</script>
 </head>

 <body>
<textarea name="src" rows="20" cols="100"></textarea>
 </body>
</html>

In EditPlus the Ctrl + B, will be the implementation of the results, sort out, is a clearer code, and now find them as long as the sentence precautionary statements, think about how to dispose of the schedule.

That string is not too much trouble to find things. Remember the Prompt text is bold red, I go directly to the output places in bold red, no fee what the work would find:

if (i.indexOf (MagicZoom.x7 ("coigmzaablav mac "))==- 1) (
a = ["^ bko) k. (~ i | ojk.za.h (bb.xk |) ga`. ah.Coigm.Taac (-6:6 <5 "," # ff0000 ", 10," bold "," center "," 100% "];
)

The author made an encrypted string, the specific algorithm can not be bothered to analyze, and direct this comment out three lines, then test, suggesting that there is no text.

=================================

Also want to say, the use of JavaScript Analyser2.0 Alpha www.xieda.org software can be decrypted directly on the script, told me almost out of hand analysis.