Now with encryption and compression

static/js/behavior.js

@@ -1,11 +1,46 @@
-
+;
 // Start random number generator seeding ASAP
 sjcl.random.startCollectors();
 
 $(function(){
 
+function encrypt(key, content) {
+  content = lzw.compress(sjcl.encrypt(key, content));
+  content = sjcl.codec.utf8String.toBits(content);
+  return sjcl.codec.base64.fromBits(content);
+}
 
+function decrypt(key, content) {
+  content = sjcl.codec.base64.toBits(content);
+  content = sjcl.codec.utf8String.fromBits(content);
+  return sjcl.decrypt(key, lzw.decompress(content));
+}
 
+function make_key() {
+  return sjcl.codec.base64.fromBits(sjcl.random.randomWords(8, 0), 0);
+}
+
+$('button[type=submit]').click(function(e){
+
+  e.preventDefault();
+  var paste = $('textarea').val();
+
+  if (paste.trim()) {
+    var expiration = $('#expiration').val();
+    var key = make_key();
+    var data = {content: encrypt(key, paste), expiration: expiration}
+
+    $.post('/paste/create', data)
+     .error(function() {
+        alert('Paste could not be saved. Please try again later.');
+     })
+     .success(function(data) {
+        alert('success');
+        window.location = '/paste/' + data + '#' + key;
+     });
+  }
+
+});
 
 
 });

static/js/lzw.js

@@ -0,0 +1,236 @@
+// Author: Anthony McKale
+//
+// Note: modifed to javascript from orginal as2 found below
+// basically identical actual to as2
+//
+//
+// http://www.razorberry.com/blog/archives/2004/08/22/lzw-compression-methods-in-as2/
+//
+// A class for LZW compression modified from code posted at the following URL's
+// http://www.shoe-box.org/blog/index.php/2004/05/05/13-CompressionLzw
+// http://www.lalex.com/blog/comments/200405/164-compression-lzw-actionscript-2.html
+//
+var lzw = {
+    // Change this variable to output an xml safe string
+    xmlsafe : false,
+    compress : function(str){
+        var dico = new Array();
+        var skipnum = lzw.xmlsafe?5:0;
+        for (var i = 0; i < 256; i++)
+        {
+            dico[String.fromCharCode(i)] = i;
+        }
+        if (lzw.xmlsafe)
+        {
+            dico["<"] = 256;
+            dico[">"] = 257;
+            dico["&"] = 258;
+            dico["\""] = 259;
+            dico["'"] = 260;
+        }
+        var res = "";
+        var txt2encode = str;
+        var splitStr = txt2encode.split("");
+        var len = splitStr.length;
+        var nbChar = 256+skipnum;
+        var buffer = "";
+        for (var i = 0; i <= len; i++)
+        {
+            var current = splitStr[i];
+            if (dico[buffer + current] !== undefined)
+            {
+                buffer += current;
+            }
+            else
+            {
+                res += String.fromCharCode(dico[buffer]);
+                dico[buffer + current] = nbChar;
+                nbChar++;
+                buffer = current;
+            }
+        }
+        return res;
+    },
+    decompress : function (str)
+    {
+        var dico = new Array();
+        var skipnum = lzw.xmlsafe?5:0;
+        for (var i = 0; i < 256; i++)
+        {
+            var c = String.fromCharCode(i);
+            dico[i] = c;
+        }
+        if (lzw.xmlsafe)
+        {
+            dico[256] = "<";
+            dico[257] = ">";
+            dico[258] = "&";
+            dico[259] = "\"";
+            dico[260] = "'";
+        }
+        var txt2encode = str;
+        var splitStr = txt2encode.split("");
+        var length = splitStr.length;
+        var nbChar = 256+skipnum;
+        var buffer = "";
+        var chaine = "";
+        var result = "";
+        for (var i = 0; i < length; i++)
+        {
+            var code = txt2encode.charCodeAt(i);
+            var current = dico[code];
+            if (buffer == "")
+            {
+                buffer = current;
+                result += current;
+            }
+            else
+            {
+                if (code <= 255+skipnum)
+                {
+                    result += current;
+                    chaine = buffer + current;
+                    dico[nbChar] = chaine;
+                    nbChar++;
+                    buffer = current;
+                }
+                else
+                {
+                    chaine = dico[code];
+                    if (chaine == undefined) chaine = buffer + buffer.slice(0,1);
+                    result += chaine;
+                    dico[nbChar] = buffer + chaine.slice(0, 1);
+                    nbChar++;
+                    buffer = chaine;
+
+                }
+            }
+        }
+        return result;
+    }
+}
+
+
+// LZW-compress a string
+function lzw_encode(s) {
+    var dict = {};
+    var data = (s + "").split("");
+    var out = [];
+    var currChar;
+    var phrase = data[0];
+    var code = 256;
+    for (var i=1; i<data.length; i++) {
+        currChar=data[i];
+        if (dict[phrase + currChar] != null) {
+            phrase += currChar;
+        }
+        else {
+            out.push(phrase.length > 1 ? dict[phrase] : phrase.charCodeAt(0));
+            dict[phrase + currChar] = code;
+            code++;
+            phrase=currChar;
+        }
+    }
+    out.push(phrase.length > 1 ? dict[phrase] : phrase.charCodeAt(0));
+    for (var i=0; i<out.length; i++) {
+        out[i] = String.fromCharCode(out[i]);
+    }
+    return out.join("");
+}
+
+// Decompress an LZW-encoded string
+function lzw_decode(s) {
+    var dict = {};
+    var data = (s + "").split("");
+    var currChar = data[0];
+    var oldPhrase = currChar;
+    var out = [currChar];
+    var code = 256;
+    var phrase;
+    for (var i=1; i<data.length; i++) {
+        var currCode = data[i].charCodeAt(0);
+        if (currCode < 256) {
+            phrase = data[i];
+        }
+        else {
+           phrase = dict[currCode] ? dict[currCode] : (oldPhrase + currChar);
+        }
+        out.push(phrase);
+        currChar = phrase.charAt(0);
+        dict[code] = oldPhrase + currChar;
+        code++;
+        oldPhrase = phrase;
+    }
+    return out.join("");
+}
+
+
+
+/* utf.js - UTF-8 <=> UTF-16 convertion
+ *
+ * Copyright (C) 1999 Masanao Izumo <iz@onicos.co.jp>
+ * Version: 1.0
+ * LastModified: Dec 25 1999
+ * This library is free.  You can redistribute it and/or modify it.
+ */
+
+/*
+ * Interfaces:
+ * utf8 = utf16to8(utf16);
+ * utf16 = utf16to8(utf8);
+ */
+
+function utf16to8(str) {
+    var out, i, len, c;
+
+    out = "";
+    len = str.length;
+    for(i = 0; i < len; i++) {
+    c = str.charCodeAt(i);
+    if ((c >= 0x0001) && (c <= 0x007F)) {
+        out += str.charAt(i);
+    } else if (c > 0x07FF) {
+        out += String.fromCharCode(0xE0 | ((c >> 12) & 0x0F));
+        out += String.fromCharCode(0x80 | ((c >>  6) & 0x3F));
+        out += String.fromCharCode(0x80 | ((c >>  0) & 0x3F));
+    } else {
+        out += String.fromCharCode(0xC0 | ((c >>  6) & 0x1F));
+        out += String.fromCharCode(0x80 | ((c >>  0) & 0x3F));
+    }
+    }
+    return out;
+}
+
+function utf8to16(str) {
+    var out, i, len, c;
+    var char2, char3;
+
+    out = "";
+    len = str.length;
+    i = 0;
+    while(i < len) {
+    c = str.charCodeAt(i++);
+    switch(c >> 4)
+    {
+      case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7:
+        // 0xxxxxxx
+        out += str.charAt(i-1);
+        break;
+      case 12: case 13:
+        // 110x xxxx   10xx xxxx
+        char2 = str.charCodeAt(i++);
+        out += String.fromCharCode(((c & 0x1F) << 6) | (char2 & 0x3F));
+        break;
+      case 14:
+        // 1110 xxxx  10xx xxxx  10xx xxxx
+        char2 = str.charCodeAt(i++);
+        char3 = str.charCodeAt(i++);
+        out += String.fromCharCode(((c & 0x0F) << 12) |
+                       ((char2 & 0x3F) << 6) |
+                       ((char3 & 0x3F) << 0));
+        break;
+    }
+    }
+
+    return out;
+}