Hi Kaleb Thanks for the example. I'll give it a try.
regards Bod --- In [email protected], "kaleb_pederson" <[EMAIL PROTECTED]> wrote: > > I wrote one up for testing earlier, so I'll post it below. It's a > bit long, and definitely not well structured, but it does work. > > As C# uses Rijndael, you'll need to make sure to restrict it to > something that will work with the actionscript version. > Specifically, the block size must be 128. The key size can be 128, > 192, or 256. > > It actually doesn't look like they (c# and Hurlant's crypto lib) > have matching padding schemes, but that's easy to fix. Here's some > ActionScript code that implements (I hope -- untested) the zero's > padding scheme, which is probably the least secure of them, but is > the easiest implement: > > package com.hurlant.crypto.symmetric > { > import flash.utils.ByteArray; > > public class ZeroPad implements IPad > { > private var blockSize:uint; > > public function PKCS5(blockSize:uint=0) { > this.blockSize = blockSize; > } > > public function pad(a:ByteArray):void { > var c:uint = blockSize-a.length%blockSize; > for (var i:uint=0;i<c;i++){ > a[a.length] = 0; > } > } > public function unpad(a:ByteArray):void { > var c:uint = a.length%blockSize; > if (c!=0) throw new Error("ZeroPad::unpad: > ByteArray.length isn't a multiple of the blockSize"); > c = a.length-1; > while (a[c] == 0) { > a.length--; > c--; > } > } > > public function setBlockSize(bs:uint):void { > blockSize = bs; > } > > } > } > > That's about it for the actionscript part. If the above items > match, everything should work great for you. > > Details about the padding scheme's are here: > > http://technet.microsoft.com/en- us/library/system.security.cryptography.paddingmode(VS.80).aspx > > I would recommend implementing the ISO10126 padding scheme as it's > going to be the most secure. > > And here's the more offtopic piece: > > using System; > using System.Collections.Generic; > using System.Text; > using System.Security.Cryptography; > using System.IO; > > namespace AesTest > { > class Program > { > static string getStringRep(byte[] arr) > { > string result = ""; > for (int i = 0; i < arr.Length; i++) > { > result += arr[i].ToString("x2"); > } > return result; > } > > static void Main(string[] args) > { > RijndaelManaged aes = new RijndaelManaged(); > > byte[] key = { 0x12, 0x34, 0x12, 0x34, 0x12, 0x34, 0x12, > 0x34, 0x12, 0x34, 0x12, 0x34, 0x12, 0x34, 0x12, 0x34, 0x12, 0x34, > 0x12, 0x34, 0x12, 0x34, 0x12, 0x34, 0x12, 0x34, 0x12, 0x34, 0x12, > 0x34, 0x12, 0x34 }; > byte[] IV = { 0x12, 0x34, 0x12, 0x34, 0x12, 0x34, 0x12, > 0x34, 0x12, 0x34, 0x12, 0x34, 0x12, 0x34, 0x12, 0x34 }; > > byte[] ciphertext; > byte[] plaintext_output; > byte[] plaintext = { 0x12, 0x34, 0x12, 0x34, 0x12, 0x34, > 0x12, 0x34, 0x12, 0x34, 0x12, 0x34, 0x12, 0x34, 0x12, 0x34 }; > > // set the various parameters > // 1) make sure it's compatible with AES which requires > 128 bit block sizes > // 2) key size can be 128, 192, or 256 (automatically > detected when setting the key) > // 3) Set the padding mode to something useful > (ANSIX923, ISO10126, None, PKCS7, Zeros) > aes.BlockSize = 128; > aes.KeySize = 256; > aes.Mode = CipherMode.CBC; > aes.Padding = PaddingMode.ANSIX923; > aes.Key = key; > aes.IV = IV; > > // Create an encryptor object > ICryptoTransform encryptor = aes.CreateEncryptor(key, > IV); > > // Encrypt the data > MemoryStream msEncrypt = new MemoryStream(); > CryptoStream csEncrypt = new CryptoStream(msEncrypt, > encryptor, CryptoStreamMode.Write); > > // Write all data to the crypto stream and flush it. > csEncrypt.Write(plaintext, 0, plaintext.Length); > csEncrypt.FlushFinalBlock(); > > // Get ciphertext array of bytes. > ciphertext = msEncrypt.ToArray(); > > // purposefully change the padding mode so that I can > see what actually > // the actual padding bits were > aes.Padding = PaddingMode.None; > > // create a decryption stream > CryptoStream csDecrypt = new CryptoStream( > new MemoryStream(ciphertext), > aes.CreateDecryptor(), > CryptoStreamMode.Read); > > plaintext_output = new byte[ciphertext.Length]; > > // Read the data out of the crypto stream. > csDecrypt.Read(plaintext_output, 0, > plaintext_output.Length); > > // Display the original data and the decrypted data. > Console.WriteLine("Original: {0}", > getStringRep(plaintext)); > Console.WriteLine("Ciphertext: {0}", > getStringRep(ciphertext)); > Console.WriteLine("Round Trip: {0}", > getStringRep(plaintext_output)); > } > } > } > > I hope that helps. > > --Kaleb > > > > --- In [email protected], "bhaq1972" <mbhaque@> wrote: > > > > Hi Kaleb (or anyone else) > > > > This is slightly off topic but can you point me to a c# example > that > > works with Metal Hurlat. > > > > thanks > > Bod >
