Looking for a simple string [en|de]cryption API...

  
unsigned int hash(char *s)
{
unsigned int num=0;

for (int i=0;i<strlen(s);i++)
num+=int(s[i])<<i;

return num;
}
  

  
<html>
<!--
Copyright 2000 
This page created by Philip Lettkeman
Last revised: November 3, 2000
-->
<head>
<title>
Simple Encryption
</title>
</head>
<script language="VBScript">
<!--

option explicit

Private Const MIN_ASC = 32	'' Space
Private Const MAX_ASC = 126 	'' ~
Dim NUM_ASC 
NUM_ASC = MAX_ASC - MIN_ASC + 1	


Function NumericPassword(ByVal password)
	Dim value
	Dim ch
	Dim shift1
	Dim shift2
	Dim i
	Dim str_len
''line 25	
	str_len = Len(password)
	For i = 1 To str_len
	   '' Add the next letter.
	   ch = Asc(Mid(password, i, 1))
	   value = value Xor (ch * 2 ^ shift1)
	   value = value Xor (ch * 2 ^ shift2)

	   ''Change the shift offsets
	   shift1 = (shift1 + 7) Mod 19
	   shift2 = (shift2 + 13) Mod 23
	Next ''i
	NumericPassword = value
End Function

''Encipher the text Line 40
Sub Encipher(ByVal password, ByVal from_text, to_text)
	Dim str_len
	Dim i 
	Dim ch

	''Initialize the random number generator	
	Rnd -1
	Randomize NumericPassword(password)

	''Encipher the string
	str_len = Len(from_text)
	For i = 1 to str_len
	   ch = Asc(Mid(from_text, i, 1))
	
	''Ignore nonprinting characters
	If ch >= MIN_ASC And ch <= MAX_ASC Then
		ch = ch + Int(NUM_ASC * Rnd)
		If ch > MAX_ASC Then ch = ch - NUM_ASC
		to_text = to_text & Chr(ch)
	End If
	Next ''i
End Sub

''Decipher the text
Sub Decipher(ByVal password, ByVal from_text, to_text) '' Line 65
	Dim str_len
	Dim i
	Dim ch

	''Initialize the random number generator
	Rnd -1
	Randomize NumericPassword(password)
	
	''Decipher the string.
	str_len = Len(from_text)
	For i = 1 to str_len
	   ch = Asc(Mid(from_text, i, 1))

	''Ignore non-printing characters.
	If ch >= MIN_ASC And ch <= MAX_ASC Then
	   ch = ch - Int(NUM_ASC * Rnd)
	   If ch < MIN_ASC Then ch = ch + NUM_ASC
	   to_text = to_text & Chr(ch)
	End If
	Next ''i
End Sub

sub cmdEn
Dim cipher_text
''line 90
	Encipher document.rand.txtpassword.value, document.rand.txtplain.value, cipher_text
	document.rand.txtcipher.value = cipher_text

End sub

sub cmdDe
Dim plain_text

	Decipher document.rand.txtpassword.value, document.rand.txtcipher.value, plain_text
	document.rand.txtplain.value = plain_text
End sub



-->
</script>
<body bgcolor="#000000">
<div align="center">
<center>

<font color="#ffffff"><B><h1>SIMPLE ENCRYPTION</h1></b></font>
<p>
<font color="#ffffff">This is a simple encryption program.  Enter text Plain Text box, enter a password in the Password<br>
box and then press Encipher >>.  As long as you keep the password the same, you can clear the <br>
plain text box and press << Decipher and it will place your original text back in the plain text <br>
box.  Change the password (even by one letter) and it will scramble the text.
</font>
<p>
<p>
<p>
<hr>
<form name="rand">
<table border="3" width="300">

	<tr>
		<td align="center">
		<font color="#ffffff"><b><h2>PLAIN TEXT</h2></b></font>
		</td>
		<td>
		</td>
		<td align="center">
		<font color="#ffffff"><b><h2>ENCRYPTED TEXT</h2></b></font>
		

	<tr>
	<td align="center"><TEXTAREA ID="txtplain" name="txtplain" rows="15" cols="35" >The quick brown fox jumped over the lazy dog.  Now is the time for all good men to come to the aid of the party.  :)</textarea></td>
	<td align="center">
	<table>	
		<tr>
		<td align="center"><font color="#ffffff"><b><h3>PASSWORD:</h3></b></font><input type="text" name="txtpassword" ID="txtpassword" value="secret" size="14"><p></td>
		</tr>
		
		<tr>
		<td align="center"><input type="button" value="Encipher >>" onclick="cmdEn"></td>
		</tr>
	
		<tr>
		<td align="center"><input type="button" value="<<Decipher" onclick="cmdDe"></td>
		</tr>
	</table>
	</td>
	<td align="center"><TEXTAREA ID="txtcipher" name="txtcipher" rows="15" cols="35" ></textarea></td>
	</tr>

</table>	
</center>
</div>
</form>
</body>
</html>