virtual public void SetCryptoMode(EncryptAlg revision, Int32 keyLength)
{
//encryptMetadata = DO_NOT_ENCRYPT_METADATA;
//embeddedFilesOnly = EMBEDDED_FILES_ONLY;
_encryptMetadata = true;
_alg = revision;
switch (_alg)
{
case EncryptAlg.STANDARD_ENCRYPTION_40:
_keyLength = 40;
break;
case EncryptAlg.STANDARD_ENCRYPTION_128:
if (keyLength > 0)
{
_keyLength = keyLength;
}
else
{
_keyLength = 128;
}
break;
case EncryptAlg.AES_128:
case EncryptAlg.AES_256:
throw new NotImplementedException("AES yet not impletmented");
default:
throw new ArgumentException("No valid encryption.mode");
}
}
void CreateEncrypt(PdfElement elem)
{
var cf = elem.Get <PdfElement>("CF");
if (cf != null)
{
var stdCf = cf.Get <PdfElement>("StdCF");
if (stdCf != null)
{
}
}
var pValue = elem.Get <PdfInteger>("P").Value;
var vValue = elem.Get <PdfInteger>("V").Value;
var rValue = elem.Get <PdfInteger>("R").Value;
var oValue = elem.Get <PdfString>("O").ToISOBytes();
var uValue = elem.Get <PdfString>("U").ToISOBytes();
var filter = elem.Get <PdfName>("Filter")?.Name;
EncryptAlg cryptoMode = EncryptAlg.STANDARD_ENCRYPTION_128;
switch (rValue)
{
case 4:
if (vValue != 4)
{
throw new PdfException($"Invalid encrypt. V={vValue}, P={vValue}");
}
var cfObj = elem.Get <PdfDictionary>("CF");
var stdCfObj = cfObj.Get <PdfDictionary>("StdCF");
if (stdCfObj != null)
{
if (stdCfObj.Get <PdfName>("CFM")?.Name == "V2")
{
cryptoMode = EncryptAlg.STANDARD_ENCRYPTION_128;
}
}
break;
default:
throw new NotImplementedException($"Decrypt value {rValue}");
}
_decryptor = new PdfEncryption();
_decryptor.SetCryptoMode(cryptoMode, 0);
if (filter == "Standard")
{
if (rValue != 5)
{
_decryptor.SetupByOwnerPassword(_documentId, uValue, oValue, pValue);
Int32 checkLen = (rValue == 3 || rValue == 4) ? 16 : 32;
if (!EqualsArray(uValue, _decryptor.UserKey, checkLen))
{
_decryptor.SetupByUserPassword(_documentId, oValue, pValue);
}
}
}
}
public static string GetFileNameWithEncryptExtension(string fileName, EncryptAlg encryptAlg)
{
return(encryptAlg switch
{
EncryptAlg.None => fileName,
EncryptAlg.AES => fileName + FileConstants.AesExtension,
EncryptAlg.Rijndael => fileName + FileConstants.RijndaelExtension,
_ => fileName
});
private async Task <bool> EncryptDataToFile(byte[] streamedFileContent, string absolutePath, EncryptAlg encryptAlg)
{
if (encryptAlg == EncryptAlg.AES)
{
var aesData = await _context.AesKeys.FirstOrDefaultAsync();
return(SymmetricCrypto.EncryptDataAndSaveToFile(streamedFileContent, aesData.Key, aesData.IV, absolutePath, CryptoAlgorithm.Aes));
}
else
{
var rijndaeData = await _context.RijndaelKeys.FirstOrDefaultAsync();
byte[] key = Convert.FromBase64String(rijndaeData.Key);
byte[] IV = Convert.FromBase64String(rijndaeData.IV);
return(SymmetricCrypto.EncryptDataAndSaveToFile(streamedFileContent, key, IV, absolutePath));
}
}
private async Task <bool> UploadFile(byte[] streamedFileContent, string absolutePath, EncryptAlg encryptAlg)
{
if (encryptAlg == EncryptAlg.None)
{
return(await FileHelpers.UploadFile(streamedFileContent, absolutePath));
}
else
{
return(await EncryptDataToFile(streamedFileContent, absolutePath, encryptAlg));
}
}
public PdfEncryption()
{
_alg = EncryptAlg.STANDARD_ENCRYPTION_40;
_keyLength = 40;
_keySize = 0;
}
