/*
 * Written by Joseph K. Myers on 2001/05/18
 * e_mayilme@hotmail.com; http://www.angelfire.com/yt/jmyers/
 */
var cipher_block_size=64, encoding_buffer=1024;
function b0f(c) {
	return c < 16 ? '0' + c.toString(16) : c.toString(16);
}
function bff(c) {
	return parseInt(c, 16);
}
function salt(s) {
	var n = 0;
	for (var i=0; i<s.length; i++) n += i&s.charCodeAt(i);
	return b0f(n%256);
}
function encrypt(s,k) {
	if (s.length > cipher_block_size) {
		var m=parseInt(s.length/cipher_block_size), t=Math.round(m/2)*cipher_block_size;
		return encrypt(s.substr(0, t), k) + encrypt(s.substr(t), k);
	}
	var r=parseInt(Math.random()*256), o=b0f(r), i;
	for (i=0; i<s.length; i++) {
		o += b0f(s.charCodeAt(i)^r^k.charCodeAt(i%k.length));
	}
	return o;
}
function decrypt(s,k) {
	var dbs = (cipher_block_size+1)*2;
	if (s.length > dbs) {
		var m=parseInt(s.length/dbs), t=Math.round(m/2)*dbs;
		return decrypt(s.substr(0, t), k) + decrypt(s.substr(t), k);
	}
	var n=bff(s.substr(0,2)), o='';
	for (var i=2; i<s.length; i+=2) {
		o += String.fromCharCode(bff(s.substr(i,2))^n^k.charCodeAt((i-2)/2%k.length));
	}
	return o;
}
function encipher(f) {
	var s=f.stream.value, k=salt(f.key.value), r=k, b=encoding_buffer,
		p=0, n=Math.floor(s.length/b)+1;
	while (n > p++) {
		self.status = 'Encrypting block ' + p + '/' + n;
		r += encrypt(s.substr((p-1)*b, b), f.key.value);
	}
	f.stream.value = r;
	self.status = 'Done';
}
function decipher(f) {
	var s=f.stream.value.substr(2), k=salt(f.key.value), r='',
		b=2*(encoding_buffer+encoding_buffer/cipher_block_size), p=0, n=Math.floor(s.length/b)+1;
	if (k != f.stream.value.substr(0, 2)) {
		if (!confirm('The key is probably incorrect.\nContinue decryption?'))
			return;
	}
	while (p++ < n) {
		self.status = 'Decrypting block ' + p + '/' + n;
		r += decrypt(s.substr((p-1)*b, b), f.key.value);
	}
	f.stream.value = r;
	return self.status = 'Done';
}