CryptDecript error

Marcio Campos

2008-05-22 13:41:01 UTC

I have a simple program in C# that encypt aand decrypt a small file that uses
CryptAPI. After I encrypt a plain file I just after that I decrypt the
cypherblock. The call to cryptdecrypt returns with error 80090005. Can
anybody help me ?

The part of the program that is in trouble is :

private void btnGerarChaveTDES_Click(object sender, EventArgs e)

{

IntPtr hProv = new IntPtr();

string pszContainer = null;

string pszProvider = "SafeSign Standard Cryptographic Service
Provider";

uint dwProvType = 1; // "1 - PROV_RSA_FULL";

uint dwFlags = 32; // "8 - CRYPT_NEWKEYSET";

int erro = 0;

CryptAcquireContext(ref hProv, pszContainer, pszProvider,
dwProvType, dwFlags);

erro = Marshal.GetLastWin32Error();

// Gera a chave TDES

// =============================================================

//IntPtr pnKey = new IntPtr();

IntPtr pnKey = new IntPtr();

uint Aldid = ((3 << 13) | (3 << 9) | (3));

uint dwFlags2 = 1; //1 - CRYPT EXPORTABLE

CryptGenKey(hProv, Aldid, dwFlags2, ref pnKey);

erro = Marshal.GetLastWin32Error();

// Importa a chava para o cartão

// =============================================================

IntPtr hExpKey = new IntPtr();

IntPtr nPubKey = new IntPtr();

uint dwFlags3 = 0;

CryptImportKey(hProv, pbData, pbData.Length, nPubKey, dwFlags3,
ref hExpKey);

erro = Marshal.GetLastWin32Error();

// Exporta a chave

// =============================================================

Int32 dwBlobType = 1; //"1 - SIMPLEBLOB";

Int32 dwFlags4 = 0;

Byte[] pbData2 = null;

Int32 pdwDataLen = 0;

CryptExportKey(pnKey, hExpKey, dwBlobType, dwFlags4, null, ref
pdwDataLen);

erro = Marshal.GetLastWin32Error();

pbData2 = new byte[pdwDataLen];

CryptExportKey(pnKey, hExpKey, dwBlobType, dwFlags4, pbData2,
ref pdwDataLen);

erro = Marshal.GetLastWin32Error();

GravarArquivo(pbData2, "c:\\BlobTDes.blb");

// Ler arquivo texto e encriptar

// =============================================================

IntPtr hHash = new IntPtr(0);

int Final = 1; // ultimo bloco ou não

uint dwFlags5 = 0;

//byte[] bufferArquivo = new byte[11027 + 130];

byte[] bufferArquivo = new byte[128];

byte[] arquivo = LerArquivo("c:\\texto.txt");

int arquivoLen = arquivo.Length;

arquivo.CopyTo(bufferArquivo, 0);

int dwBufLen = bufferArquivo.Length;

CryptEncrypt(pnKey, hHash, Final, dwFlags5, bufferArquivo, ref
arquivoLen, dwBufLen);

erro = Marshal.GetLastWin32Error();

//byte[] aux = new byte[arquivoLen];

//for (int i = 0; i < aux.Length; i++)

// aux[i] = bufferArquivo[i];

////GravarArquivo(bufferArquivo, "c:\\texto_cripto.txt");

//GravarArquivo(aux, "c:\\texto_cripto.txt");

//// Zera o vetor de incializaçao

//// =============================================================

//uint dwParam = 1; // 1 - KP_IV

//byte[] pbData3 = new byte[8];

//uint dwFlags6 = 0;

//for (int i = 0; i < 8; i++)

// pbData3[i] = 0;

//bool bln1 = CryptSetKeyParam(pnKey, dwParam, pbData3, dwFlags6);

//erro = Marshal.GetLastWin32Error();

bool bln2 = CryptDecrypt(pnKey, hHash, Final, dwFlags5, ref
bufferArquivo, ref arquivoLen);

erro = Marshal.GetLastWin32Error();

}