privacyguides.org/js/build/packer.js
2015-07-08 14:30:48 +02:00

317 lines
12 KiB
JavaScript

/*
packer, version 2.0.2 (2005-08-19)
Copyright 2004-2005, Dean Edwards
License: http://creativecommons.org/licenses/LGPL/2.1/
*/
function pack(_script, _encoding, _fastDecode, _specialChars) {
// constants
var $IGNORE = "$1";
// validate parameters
_script += "\n";
_encoding = Math.min(parseInt(_encoding), 95);
// apply all parsing routines
function _pack($script) {
var i, $parse;
for (i = 0; ($parse = _parsers[i]); i++) {
$script = $parse($script);
}
return $script;
};
// unpacking function - this is the boot strap function
// data extracted from this packing routine is passed to
// this function when decoded in the target
var _unpack = function($packed, $ascii, $count, $keywords, $encode, $decode) {
while ($count--)
if ($keywords[$count])
$packed = $packed.replace(new RegExp('\\b' + $encode($count) + '\\b', 'g'), $keywords[$count]);
return $packed;
};
// code-snippet inserted into the unpacker to speed up decoding
var _decode = function() {
// does the browser support String.replace where the
// replacement value is a function?
if (!''.replace(/^/, String)) {
// decode all the values we need
while ($count--) $decode[$encode($count)] = $keywords[$count] || $encode($count);
// global replacement function
$keywords = [function($encoded){return $decode[$encoded]}];
// generic match
$encode = function(){return'\\w+'};
// reset the loop counter - we are now doing a global replace
$count = 1;
}
};
// keep a list of parsing functions, they'll be executed all at once
var _parsers = [];
function _addParser($parser) {
_parsers[_parsers.length] = $parser;
};
// zero encoding - just removal of white space and comments
function _basicCompression($script) {
var $parser = new ParseMaster;
// make safe
$parser.escapeChar = "\\";
// protect strings
$parser.add(/'[^'\n\r]*'/, $IGNORE);
$parser.add(/"[^"\n\r]*"/, $IGNORE);
// remove comments
$parser.add(/\/\/[^\n\r]*[\n\r]/, " ");
$parser.add(/\/\*[^*]*\*+([^\/][^*]*\*+)*\//, " ");
// protect regular expressions
$parser.add(/\s+(\/[^\/\n\r\*][^\/\n\r]*\/g?i?)/, "$2"); // IGNORE
$parser.add(/[^\w\x24\/'"*)\?:]\/[^\/\n\r\*][^\/\n\r]*\/g?i?/, $IGNORE);
// remove: ;;; doSomething();
if (_specialChars) $parser.add(/;;;[^\n\r]+[\n\r]/);
// remove redundant semi-colons
$parser.add(/\(;;\)/, $IGNORE); // protect for (;;) loops
$parser.add(/;+\s*([};])/, "$2");
// apply the above
$script = $parser.exec($script);
// remove white-space
$parser.add(/(\b|\x24)\s+(\b|\x24)/, "$2 $3");
$parser.add(/([+\-])\s+([+\-])/, "$2 $3");
$parser.add(/\s+/, "");
// done
return $parser.exec($script);
};
function _encodeSpecialChars($script) {
var $parser = new ParseMaster;
// replace: $name -> n, $$name -> na
$parser.add(/((\x24+)([a-zA-Z$_]+))(\d*)/, function($match, $offset) {
var $length = $match[$offset + 2].length;
var $start = $length - Math.max($length - $match[$offset + 3].length, 0);
return $match[$offset + 1].substr($start, $length) + $match[$offset + 4];
});
// replace: _name -> _0, double-underscore (__name) is ignored
var $regexp = /\b_[A-Za-z\d]\w*/;
// build the word list
var $keywords = _analyze($script, _globalize($regexp), _encodePrivate);
// quick ref
var $encoded = $keywords.$encoded;
$parser.add($regexp, function($match, $offset) {
return $encoded[$match[$offset]];
});
return $parser.exec($script);
};
function _encodeKeywords($script) {
// escape high-ascii values already in the script (i.e. in strings)
if (_encoding > 62) $script = _escape95($script);
// create the parser
var $parser = new ParseMaster;
var $encode = _getEncoder(_encoding);
// for high-ascii, don't encode single character low-ascii
var $regexp = (_encoding > 62) ? /\w\w+/ : /\w+/;
// build the word list
$keywords = _analyze($script, _globalize($regexp), $encode);
var $encoded = $keywords.$encoded;
// encode
$parser.add($regexp, function($match, $offset) {
return $encoded[$match[$offset]];
});
// if encoded, wrap the script in a decoding function
return $script && _bootStrap($parser.exec($script), $keywords);
};
function _analyze($script, $regexp, $encode) {
// analyse
// retreive all words in the script
var $all = $script.match($regexp);
var $$sorted = []; // list of words sorted by frequency
var $$encoded = {}; // dictionary of word->encoding
var $$protected = {}; // instances of "protected" words
if ($all) {
var $unsorted = []; // same list, not sorted
var $protected = {}; // "protected" words (dictionary of word->"word")
var $values = {}; // dictionary of charCode->encoding (eg. 256->ff)
var $count = {}; // word->count
var i = $all.length, j = 0, $word;
// count the occurrences - used for sorting later
do {
$word = "$" + $all[--i];
if (!$count[$word]) {
$count[$word] = 0;
$unsorted[j] = $word;
// make a dictionary of all of the protected words in this script
// these are words that might be mistaken for encoding
$protected["$" + ($values[j] = $encode(j))] = j++;
}
// increment the word counter
$count[$word]++;
} while (i);
// prepare to sort the word list, first we must protect
// words that are also used as codes. we assign them a code
// equivalent to the word itself.
// e.g. if "do" falls within our encoding range
// then we store keywords["do"] = "do";
// this avoids problems when decoding
i = $unsorted.length;
do {
$word = $unsorted[--i];
if ($protected[$word] != null) {
$$sorted[$protected[$word]] = $word.slice(1);
$$protected[$protected[$word]] = true;
$count[$word] = 0;
}
} while (i);
// sort the words by frequency
$unsorted.sort(function($match1, $match2) {
return $count[$match2] - $count[$match1];
});
j = 0;
// because there are "protected" words in the list
// we must add the sorted words around them
do {
if ($$sorted[i] == null) $$sorted[i] = $unsorted[j++].slice(1);
$$encoded[$$sorted[i]] = $values[i];
} while (++i < $unsorted.length);
}
return {$sorted: $$sorted, $encoded: $$encoded, $protected: $$protected};
};
// build the boot function used for loading and decoding
function _bootStrap($packed, $keywords) {
var $ENCODE = _safeRegExp("$encode\\($count\\)", "g");
// $packed: the packed script
$packed = "'" + _escape($packed) + "'";
// $ascii: base for encoding
var $ascii = Math.min($keywords.$sorted.length, _encoding) || 1;
// $count: number of words contained in the script
var $count = $keywords.$sorted.length;
// $keywords: list of words contained in the script
for (var i in $keywords.$protected) $keywords.$sorted[i] = "";
// convert from a string to an array
$keywords = "'" + $keywords.$sorted.join("|") + "'.split('|')";
// $encode: encoding function (used for decoding the script)
var $encode = _encoding > 62 ? _encode95 : _getEncoder($ascii);
$encode = String($encode).replace(/_encoding/g, "$ascii").replace(/arguments\.callee/g, "$encode");
var $inline = "$count" + ($ascii > 10 ? ".toString($ascii)" : "");
// $decode: code snippet to speed up decoding
if (_fastDecode) {
// create the decoder
var $decode = _getFunctionBody(_decode);
if (_encoding > 62) $decode = $decode.replace(/\\\\w/g, "[\\xa1-\\xff]");
// perform the encoding inline for lower ascii values
else if ($ascii < 36) $decode = $decode.replace($ENCODE, $inline);
// special case: when $count==0 there are no keywords. I want to keep
// the basic shape of the unpacking funcion so i'll frig the code...
if (!$count) $decode = $decode.replace(_safeRegExp("($count)\\s*=\\s*1"), "$1=0");
}
// boot function
var $unpack = String(_unpack);
if (_fastDecode) {
// insert the decoder
$unpack = $unpack.replace(/\{/, "{" + $decode + ";");
}
$unpack = $unpack.replace(/"/g, "'");
if (_encoding > 62) { // high-ascii
// get rid of the word-boundaries for regexp matches
$unpack = $unpack.replace(/'\\\\b'\s*\+|\+\s*'\\\\b'/g, "");
}
if ($ascii > 36 || _encoding > 62 || _fastDecode) {
// insert the encode function
$unpack = $unpack.replace(/\{/, "{$encode=" + $encode + ";");
} else {
// perform the encoding inline
$unpack = $unpack.replace($ENCODE, $inline);
}
// pack the boot function too
$unpack = pack($unpack, 0, false, true);
// arguments
var $params = [$packed, $ascii, $count, $keywords];
if (_fastDecode) {
// insert placeholders for the decoder
$params = $params.concat(0, "{}");
}
// the whole thing
return "eval(" + $unpack + "(" + $params + "))\n";
};
// mmm.. ..which one do i need ??
function _getEncoder($ascii) {
return $ascii > 10 ? $ascii > 36 ? $ascii > 62 ? _encode95 : _encode62 : _encode36 : _encode10;
};
// zero encoding
// characters: 0123456789
var _encode10 = function($charCode) {
return $charCode;
};
// inherent base36 support
// characters: 0123456789abcdefghijklmnopqrstuvwxyz
var _encode36 = function($charCode) {
return $charCode.toString(36);
};
// hitch a ride on base36 and add the upper case alpha characters
// characters: 0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ
var _encode62 = function($charCode) {
return ($charCode < _encoding ? '' : arguments.callee(parseInt($charCode / _encoding))) +
(($charCode = $charCode % _encoding) > 35 ? String.fromCharCode($charCode + 29) : $charCode.toString(36));
};
// use high-ascii values
var _encode95 = function($charCode) {
return ($charCode < _encoding ? '' : arguments.callee($charCode / _encoding)) +
String.fromCharCode($charCode % _encoding + 161);
};
// special _chars
var _encodePrivate = function($charCode) {
return "_" + $charCode;
};
// protect characters used by the parser
function _escape($script) {
return $script.replace(/([\\'])/g, "\\$1");
};
// protect high-ascii characters already in the script
function _escape95($script) {
return $script.replace(/[\xa1-\xff]/g, function($match) {
return "\\x" + $match.charCodeAt(0).toString(16);
});
};
function _safeRegExp($string, $flags) {
return new RegExp($string.replace(/\$/g, "\\$"), $flags);
};
// extract the body of a function
function _getFunctionBody($function) {
with (String($function)) return slice(indexOf("{") + 1, lastIndexOf("}"));
};
// set the global flag on a RegExp (you have to create a new one)
function _globalize($regexp) {
return new RegExp(String($regexp).slice(1, -1), "g");
};
// build the parsing routine
_addParser(_basicCompression);
if (_specialChars) _addParser(_encodeSpecialChars);
if (_encoding) _addParser(_encodeKeywords);
// go!
return _pack(_script);
};