Encryption \ Decryption URL transfer parameters in the Web system.

web| Encryption | Decryption network Many people are asking how to implement Web System URL transfer (form submission) parameter encryption. For example: To do a user account editing, to pass the user's id,url as follows: http://localhost/mysystem/editAccounts.aspx?ID=2
But do not want to let others know that the user ID is 2, malicious users may also change 2 to another user ID.
The parameter values passed by encryption can solve the problem.
The following is the base class of DEC encryption and decryption that you wrote.

FileName: Security.CS

Using System;
Using System.Security.Cryptography;
Using System.IO;
Using System.Text;

Namespace EIP. Framework
{
///
A summary description of the security.
The security class implements encryption and decryption under the. NET Framework.
CopyRight kangsoft@hotmail.com@hotmail.com@hotmail.com
///
public class Security
{
String _querystringkey = "ABCDEFGH"; URL Transport parameter Encryption key
String _passwordkey = "HGFEDCBA"; Password encryption key

Public Security ()
{
//
TODO: Add constructor logic here
//
}

///
Encrypted string for URL transmission
///
///
///
public string encryptquerystring (string querystring)
{
Return Encrypt (Querystring,_querystringkey);
}

///
Decrypting a string transmitted by a URL
///
///
///
public string decryptquerystring (string querystring)
{
Return Decrypt (Querystring,_querystringkey);
}

///
Encrypt account password
///
///
///
public string Encryptpassword (string PassWord)
{
Return Encrypt (Password,_passwordkey);
}

///
Decrypt account password
///
///
///
public string Decryptpassword (string PassWord)
{
Return Decrypt (Password,_passwordkey);
}

///
DEC Encryption Process
///
///
///
///
public string Encrypt (String ptoencrypt,string sKey)
{
DESCryptoServiceProvider des = new DESCryptoServiceProvider (); Put the string in the byte array

byte[] Inputbytearray = Encoding.Default.GetBytes (Ptoencrypt);
Byte[] Inputbytearray=encoding.unicode.getbytes (ptoencrypt);

Des. Key = ASCIIEncoding.ASCII.GetBytes (SKey); Establish keys and offsets for encrypted objects
DES.IV = ASCIIEncoding.ASCII.GetBytes (SKey); GetBytes method of using Asciiencoding.ascii method in original text
MemoryStream ms = new MemoryStream (); Make input password must enter English text
CryptoStream cs = new CryptoStream (ms,des. CreateEncryptor (), cryptostreammode.write);

Cs. Write (Inputbytearray, 0, inputbytearray.length);
Cs. FlushFinalBlock ();

StringBuilder ret = new StringBuilder ();
foreach (Byte b in Ms.) ToArray ())
{
Ret. AppendFormat ("{0:x2}", b);
}
Ret. ToString ();
return ret. ToString ();
}

///
DEC decryption Process
///
///
///
///
public string Decrypt (string ptodecrypt, String SKey)
{
DESCryptoServiceProvider des = new DESCryptoServiceProvider ();

byte[] Inputbytearray = new BYTE[PTODECRYPT.LENGTH/2];
for (int x = 0; x < PTODECRYPT.LENGTH/2 + +)
{
int i = (Convert.ToInt32 (ptodecrypt.substring (x * 2, 2), 16));
INPUTBYTEARRAY[X] = (byte) i;
}

Des. Key = ASCIIEncoding.ASCII.GetBytes (SKey); Establishes the key and offset for the encrypted object, which is important and cannot be modified
DES.IV = ASCIIEncoding.ASCII.GetBytes (SKey);
MemoryStream ms = new MemoryStream ();
CryptoStream cs = new CryptoStream (MS, Des. CreateDecryptor (), cryptostreammode.write);

Cs. Write (Inputbytearray, 0, inputbytearray.length);
Cs. FlushFinalBlock ();

StringBuilder ret = new StringBuilder (); To create a Stringbuild object, Createdecrypt uses a stream object and must turn the decrypted text into a stream object

Return System.Text.Encoding.Default.GetString (Ms. ToArray ());
}

///
Check if the encrypted string is the same as the original
///
///
///
///
///
public bool Validatestring (string enstring, string fostring, int Mode)
{
Switch (Mode)
{
Default
Case 1:
if (Decrypt (enstring,_querystringkey) = = Fostring.tostring ())
{
return true;
}
Else
{
return false;
}
Case 2:
if (Decrypt (enstring,_passwordkey) = = Fostring.tostring ())
{
return true;
}
Else
{
return false;
}
}
}
}
}

A different key is used for the URL and account encryption in the class. The call URL encryption process is as follows:
Eip. Framework.security objsecurity = new EIP. Framework.security ();
Objsecurity.encryptquerystring (' Strings to be encrypted ');

Decryption: objsecurity.decryptquerystring (' passed parameters ');