TDES sifra

[smrtak_]

Potreboval bych poradit se sifrou TRIPLE DES.
Mam program, kterej v pohode desifruje pomoci 128 bitovyho klice mail.... a ja delam podobny program v .NET C# a prave na tom desifrovani mi to lehne... pry spatny data.
Pri tom vim, ze mam ten samy klic a je to to stejna sifra TDES (ECB mod).
Dokonce mam i zdrojaky toho programu v pascalu.

Nevite nekdo cim to je ??

[Absurdus]

veru neviem
a z takeho nejasneho popisu ani nikto vediet nebude...

mas vlastnu implementaciu 3des alebo pouzivas OpenSSL?
a tipujem ze tych 128 bitov, su vlastne dva 8bytove kluce a teda mas 3des, kde k1=k3

napis proste nieco viac...

[smrtak_]

veru neviem
a z takeho nejasneho popisu ani nikto vediet nebude...

mas vlastnu implementaciu 3des alebo pouzivas OpenSSL?
a tipujem ze tych 128 bitov, su vlastne dva 8bytove kluce a teda mas 3des, kde k1=k3

napis proste nieco viac...

Mam sifru 3DES implementovanou v .NET framevorku a chci vedet, jestli ten algoritmus ty sifry je stejny jak v unitech v pascalu ("desunit2.pas...")
tot je vse... (protoze mi to nejde descriptovat)

[Absurdus]

jasne ze algoritmus je ten isty, sifra DES je dana standartom, vsetky jej implementacie by mali byt rovnake...

skontroluj si ci mas nastaveny spravny mod (mozno ma napr. .NET default CBC mod), ci mas spravny IV, spravne nastaveny typ kluca a pod. ...

[smrtak_]

jasne ze algoritmus je ten isty, sifra DES je dana standartom, vsetky jej implementacie by mali byt rovnake...

skontroluj si ci mas nastaveny spravny mod (mozno ma napr. .NET default CBC mod), ci mas spravny IV, spravne nastaveny typ kluca a pod. ...

-mode je urcite stejny (ECB)
-klyc je take urcite stejny
-IV vektor nevim, ale vetsinou je stejny jako klyc... i kdyz na nem nezalizi... pri nejhorsim se nezobrazi prvnich 8 znaku
-data jsou take stejna...

Fakt nevim uz cim to je....

[Absurdus]

aku konkretne dostanes chybovu hlasku?

nie je problem napr. v paddingu? mas dlzku spravy nasobok 8 ?

[smrtak_]

aku konkretne dostanes chybovu hlasku?

nie je problem napr. v paddingu? mas dlzku spravy nasobok 8 ?

"chybna data!" ... pokud vypnut padding, dam tam zero ... tak to probehne, ale desifruje se to spatne! Fakt nevim cim to je... nevis jestli se neda zmenit buffer na velikost bloku na 8 znaku ?? (neco takovyho jsem vydel v tom pascalovym unitu)

[Absurdus]

nevis jestli se neda zmenit buffer na velikost bloku na 8 znaku ??

neviem co tym myslis - DES ma velkost bloku 8 bytov, vzdy sa desifruje iba osem bytov...

skus padding FF ...
inak uz fakt neviem

[smrtak_]

nevis jestli se neda zmenit buffer na velikost bloku na 8 znaku ??

neviem co tym myslis - DES ma velkost bloku 8 bytov, vzdy sa desifruje iba osem bytov...

skus padding FF ...
inak uz fakt neviem

Co je to FF Zalezi vubec na tom ?? neni to jen zakonceni ?? me staci videt aspon kousek desifrovanych dat...

[Absurdus]

FF alias 255 alias paddovanie jednotkami a nie nulami...

uz fakt neviem, cim by to mohlo byt...

ak ten program nie je moc velky, pastni ho sem, alebo mi ho posli ako spravu... v .NET budem aj ja za chvilu nieco robit so sifrovanim,
tak si to aspon trochu nacvicim...

[smrtak_]

moje zdrojovy kody.... pokud chces unitu z pascalu tak napis

public static void EncryptData(String inName, String outName, byte[] rijnKey, byte[] rijnIV)
		{    
			//Create the file streams to handle the input and output files.
			FileStream fin = new FileStream(inName, FileMode.Open, FileAccess.Read);
			FileStream fout = new FileStream(outName, FileMode.OpenOrCreate, FileAccess.Write);
			fout.SetLength(0);
       
			//Create variables to help with read and write.
			byte[] bin = new byte[100]; //This is intermediate storage for the encryption.
			long rdlen = 0;              //This is the total number of bytes written.
			long totlen = fin.Length;    //This is the total length of the input file.
			int len;                     //This is the number of bytes to be written at a time.
 
			//SymmetricAlgorithm tdes = SymmetricAlgorithm.Create("TDES"); //Creates the default implementation, which is RijndaelManaged.         
			
			TripleDESCryptoServiceProvider tdes = new TripleDESCryptoServiceProvider();
						
			tdes.Mode = System.Security.Cryptography.CipherMode.ECB;
			tdes.Padding = System.Security.Cryptography.PaddingMode.Zeros; 
			
			CryptoStream encStream = new CryptoStream(fout, tdes.CreateEncryptor(rijnKey, rijnIV), CryptoStreamMode.Write);
                
			Console.WriteLine("Encrypting...");
 
			//Read from the input file, then encrypt and write to the output file.
			while&#40;rdlen < totlen&#41;
			&#123;
				len = fin.Read&#40;bin, 0, 100&#41;;
				encStream.Write&#40;bin, 0, len&#41;;
				rdlen = rdlen + len;
				Console.WriteLine&#40;"&#123;0&#125; bytes processed", rdlen&#41;;
			&#125;
 
			encStream.Close&#40;&#41;;  
			fout.Close&#40;&#41;;
			fin.Close&#40;&#41;;                
		&#125;

		public static void DescryptData&#40;String inName, String outName, byte&#91;&#93; rijnKey, byte&#91;&#93; rijnIV&#41;
		&#123;    
			//Create the file streams to handle the input and output files.
			FileStream fin = new FileStream&#40;inName, FileMode.Open, FileAccess.Read&#41;;
			FileStream fout = new FileStream&#40;outName, FileMode.OpenOrCreate, FileAccess.Write&#41;;
			fout.SetLength&#40;0&#41;;
       
			//Create variables to help with read and write.
			byte&#91;&#93; bin = new byte&#91;100&#93;; //This is intermediate storage for the encryption.
			long rdlen = 0;              //This is the total number of bytes written.
			long totlen = fin.Length;    //This is the total length of the input file.
			int len;                     //This is the number of bytes to be written at a time.
 
			//SymmetricAlgorithm tdes = SymmetricAlgorithm.Create&#40;&#41;; //Creates the default implementation, which is RijndaelManaged.         
			System.Security.Cryptography.TripleDESCryptoServiceProvider tdes = new TripleDESCryptoServiceProvider&#40;&#41;;
			tdes.Mode = System.Security.Cryptography.CipherMode.ECB;
			tdes.Padding = System.Security.Cryptography.PaddingMode.Zeros; 
			
			CryptoStream encStream = new CryptoStream&#40;fout, tdes.CreateDecryptor&#40;rijnKey, rijnIV&#41;, CryptoStreamMode.Write&#41;;
                
			Console.WriteLine&#40;"Descrypting..."&#41;;
 
			//Read from the input file, then encrypt and write to the output file.
			while&#40;rdlen < totlen&#41;
			&#123;
				len = fin.Read&#40;bin, 0, 100&#41;;
				encStream.Write&#40;bin, 0, len&#41;;
				rdlen = rdlen + len;
				Console.WriteLine&#40;"&#123;0&#125; bytes processed", rdlen&#41;;
			&#125;
 
			encStream.Close&#40;&#41;;  
			fout.Close&#40;&#41;;
			fin.Close&#40;&#41;;                   
		&#125;

[Absurdus]

hm, tu chyba nie je (kedze je to vlastne upraveny example )
este by si mohol poslat kod kde nastavujes kluc a volas tutu funkciu...

inak, musis to robit v .NET ??

pomocou OpenSSL na desifrovanie staci

void des3_decrypt(const byte *input, byte *output, size_t length, 
                            byte *key1, byte *key2, byte *key3)
{
  des_key_schedule ks1, ks2, ks3;
  
  des_set_key_unchecked((des_cblock *) key1, ks1);
  des_set_key_unchecked((des_cblock *) key2, ks2);
  des_set_key_unchecked((des_cblock *) key3, ks3);

  // initialisaton vector (set to 0)
  des_cblock iv = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };

  des_ede3_cbc_encrypt(input, output, length, ks1, ks2, ks3, &iv, 
    DES_DECRYPT);
}

[smrtak_]

tak tady to je, tady se vola ten kod

jo, jeste jsem mohl napsat, ze muzu jakykoliv data encryptovat a v pohode descryptovat... to funguje , ale ty mailovy date ne...

static void Main(string[] args)
		{
			Console.WriteLine("TDES Encryptor & Desryptor.... smrtak");
			
			Console.Write("Encrypt or Descrypt ?? (e/d) :");
			string mode = Console.ReadLine();
			Console.Write("File to read: ");
			string read = Console.ReadLine();
			Console.Write("File to write: ");
			string write = Console.ReadLine();
			Console.Write("password(md5hash): ");
			string skey = Console.ReadLine();

			//key
			MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();
			byte[] key = md5.ComputeHash(System.Text.ASCIIEncoding.ASCII.GetBytes(skey),0,skey.Length);
			//vypis klic v hexa
			Console.Write("Password : ");
			for&#40;int i = 0;i < key.Length;i++&#41;
				Console.Write&#40;"&#123;0&#58;X&#125;",key&#91;i&#93;&#41;;
			Console.WriteLine&#40;&#41;;
			//run
			if&#40;mode.ToUpper&#40;&#41; == "E"&#41;
				TDES.EncryptData&#40;read,write,key,key&#41;;
			else
			if&#40;mode.ToUpper&#40;&#41; == "D"&#41;
				TDES.DescryptData&#40;read,write,key,key&#41;;

			Console.ReadLine&#40;&#41;;
		&#125;

[smrtak_]

Mozna bude lepsi poslat cely zdrojaky i s exe souborem

http://www.eprumka.wz.cz/des/des.exe exe soubor

http://www.eprumka.wz.cz/des/des_kod.zip zdrojove kody

ps: v dotnetu je to jednodussi (hlavne pro velke projekty)

Jestli budes chtit poslu ti ten datovej soubor co nejde desifrovat i s heslem .... Stacilo by, kdyby se ti to podarilo desifrovat kdekoliv ....

diky

[Absurdus]

na *.zip pise mi not_found...
posli data aj heslo, desifrujem to u seba cez OpenSSL

P.S. neverim ze je to jednoduchsie, ja OpenSSL pouzivam
v naozaj velkom projekte... spolu s ACE, a s OTL pre databazu