internal static Stream Decrypt(Stream aStream, TEncryptionData Encryption)
{
using (TOle2File DataStream = new TOle2File(aStream, false))
{
DataStream.SelectStream(XlsxConsts.EncryptionInfoString);
byte[] RecordHeader = new byte[4 * 2];
DataStream.Read(RecordHeader, RecordHeader.Length);
int vMajor = BitOps.GetWord(RecordHeader, 0);
int vMinor = BitOps.GetWord(RecordHeader, 2);
if ((vMajor == 0x03 || vMajor == 0x04) && vMinor == 0x02)
{
long Flags = BitOps.GetCardinal(RecordHeader, 4);
if (Flags == 0x10)
{
XlsMessages.ThrowException(XlsErr.ErrNotSupportedEncryption); //external encryption
}
return(ReadStandardEncryptionInfo(DataStream, Encryption));
}
else if (vMajor == 4 && vMinor == 4 && BitOps.GetCardinal(RecordHeader, 4) == 0x040)
{
return(ReadAgileEncryptionInfo(DataStream, Encryption));
}
XlsMessages.ThrowException(XlsErr.ErrNotSupportedEncryption);
return(null);
}
}
private static object[] GetNameDictionary(TOle2File Ole2File)
{
byte[] PropCountArray = new byte[4];
Ole2File.Read(PropCountArray, PropCountArray.Length);
Int32 PropCount = BitOps.GetInt32(PropCountArray, 0);
object[] Properties = new object[PropCount];
for (int i = 0; i < Properties.Length; i++)
{
TUnconvertedOlePropertyName PropName = new TUnconvertedOlePropertyName();
Ole2File.Read(PropCountArray, PropCountArray.Length);
PropName.Id = BitConverter.ToUInt32(PropCountArray, 0);
Ole2File.Read(PropCountArray, PropCountArray.Length);
int StrLen = BitOps.GetInt32(PropCountArray, 0);
if (StrLen <= 1)
{
PropName.Name = new TUnconvertedString(new byte[0], false); //StrLen includes the trailing #0
}
else
{
byte[] Str = new byte[StrLen - 1];
Ole2File.Read(Str, Str.Length);
Ole2File.SeekForward(Ole2File.Position + 1); //go over the 0 byte. This is needed for vectors/arrays.
PropName.Name = new TUnconvertedString(Str, false);
}
Properties[i] = PropName;
}
return(Properties);
}
private static Stream DecryptStream(TOle2File DataStream, TEncryptionParameters EncParams, TEncryptionKey Key)
{
DataStream.SelectStream(XlsxConsts.ContentString);
byte[] EncryptedSize = new byte[8];
DataStream.Read(EncryptedSize, EncryptedSize.Length);
AesManaged Engine = null;
ICryptoTransform Decryptor = null;
try
{
Engine = TEncryptionUtils.CreateEngine(EncParams);
if (!Key.VariableIV)
{
Decryptor = Engine.CreateDecryptor(Key.Key, Key.IV);
}
return(new TXlsxCryptoStreamReader(DataStream, BitOps.GetCardinal(EncryptedSize, 0), Engine, Decryptor, Key));
}
catch
{
if (Engine != null)
{
((IDisposable)Engine).Dispose();
}
if (Decryptor != null)
{
Decryptor.Dispose();
}
throw;
}
}
private void FinishEncryption()
{
TEncryptionParameters EncParams = GetEncryptionParams(Protection);
AesManaged EncEngine = TEncryptionUtils.CreateEngine(EncParams);
TAgileEncryptionKey DataKey = TAgileEncryptionKey.CreateForWriting(null, EncEngine.KeySize / 8);
DataKey.Key = TEncryptionUtils.GetRandom(DataKey.KeySizeInBytes);
TAgileEncryptionKey KeyKey = TAgileEncryptionKey.CreateForWriting(Protection.OpenPassword, EncEngine.KeySize / 8);
byte[] WorkLen = new byte[8];
BitOps.SetCardinal(WorkLen, 0, WorkingStream.Length - WorkStreamZeroPos);
EncryptStream(EncEngine, DataKey, WorkLen);
using (MemoryStream ms = new MemoryStream())
{
using (TOle2File Ole2File = new TOle2File(GetEmptyEncryptedFile()))
{
Ole2File.PrepareForWrite(ms, XlsxConsts.EncryptionInfoString, new string[0]);
CreateInfoStream(Ole2File, EncEngine, EncParams, KeyKey, DataKey);
}
ms.Position = 0;
using (TOle2File Ole2File = new TOle2File(ms))
{
Ole2File.PrepareForWrite(TargetStream, XlsxConsts.ContentString, new string[0]);
WorkingStream.Position = 0;
TEncryptionUtils.CopyStream(WorkingStream, Ole2File);
}
}
}
internal TXlsRecordLoader(TOle2File aDataStream, TBiff8XFMap aXFMap, TSST aSST, IFlexCelFontList aFontList, TBorderList aBorderList,
TPatternList aPatternList, TEncryptionData aEncryption, TXlsBiffVersion aXlsBiffVersion, TNameRecordList aNames, TVirtualReader VirtualReader)
: base(aSST, aFontList, aEncryption, aXlsBiffVersion, aXFMap, aNames, VirtualReader)
{
DataStream = aDataStream;
BorderList = aBorderList;
PatternList = aPatternList;
}
internal void Load(TOle2File OleFile)
{
PropertyList.Clear();
CheckHeader(OleFile);
ReadPropHeader(OleFile);
ReadPropSectionHeader(OleFile);
}
public TXlsxCryptoStreamReader(TOle2File aDataStream, long aStreamLen, AesManaged aEncEncgine, ICryptoTransform aDecryptor, TEncryptionKey aKey)
{
DataStream = aDataStream;
FStreamLen = aStreamLen;
EncEngine = aEncEncgine;
Decryptor = aDecryptor;
CurrentSegment = new byte[SegmentSize];
Key = aKey;
}
internal void WriteHeader(TOle2File OleFile)
{
OleFile.WriteRaw(PropHeader, PropHeader.Length);
int SectCount = (int)BitOps.GetCardinal(PropHeader, 24);
for (int i = 0; i < SectCount; i++)
{
OleFile.WriteRaw(FmtSection[i], FmtSection[i].Length);
}
}
internal static void CopyStream(Stream SourceStream, TOle2File DataStream)
{
byte[] buffer = new byte[8192];
int read;
while ((read = SourceStream.Read(buffer, 0, buffer.Length)) > 0)
{
DataStream.Write(buffer, 0, read);
}
}
private void ReadPropHeader(TOle2File OleFile)
{
int SectCount = (int)BitOps.GetCardinal(PropHeader, 24);
FmtSection = new byte[SectCount][];
for (int i = 0; i < SectCount; i++)
{
FmtSection[i] = new byte[16 + 4];
OleFile.Read(FmtSection[i], FmtSection[i].Length);
}
long SectorOffset = BitOps.GetCardinal(FmtSection[0], 16);
OleFile.SeekForward(SectorOffset);
}
private void CreateInfoStream(TOle2File DataStream, AesManaged EncEngine, TEncryptionParameters EncParams, TAgileEncryptionKey KeyKey, TAgileEncryptionKey DataKey)
{
DataStream.Write16(0x0004);
DataStream.Write16(0x0004);
DataStream.Write32(0x00040);
byte[] InfoStreamXml = GetInfoStreamXml(EncEngine, EncParams, KeyKey, DataKey);
DataStream.Write(InfoStreamXml, InfoStreamXml.Length);
byte[] pad = new byte[4098 - InfoStreamXml.Length]; //Our Ole2 implementation will fill a sector with 0 so it doesn't go to the ministream. Those 0 will confuse Excel, so we will write spaces.
for (int i = 0; i < pad.Length; i++)
{
pad[i] = 32;
}
DataStream.Write(pad, pad.Length);
}
private void CheckHeader(TOle2File OleFile)
{
PropHeader = new byte[2 + 2 + 4 + 16 + 4];
OleFile.Read(PropHeader, PropHeader.Length);
byte[] ExpectedHeader = { 0xFE, 0xFF, 0x00, 0x00 };
for (int i = 0; i < ExpectedHeader.Length; i++)
{
if (ExpectedHeader[i] != PropHeader[i])
{
XlsMessages.ThrowException(XlsErr.ErrInvalidPropertySector);
}
}
if (BitOps.GetCardinal(PropHeader, 24) < 1) //There should be at least one property section.
{
XlsMessages.ThrowException(XlsErr.ErrInvalidPropertySector);
}
}
private static Stream ReadAgileEncryptionInfo(TOle2File DataStream, TEncryptionData Encryption)
{
byte[] Enc = new byte[DataStream.Length - DataStream.Position];
DataStream.Read(Enc, Enc.Length);
TEncryptionParameters DataEncParams = new TEncryptionParameters();
TAgileEncryptionKey DataKey = new TAgileEncryptionKey();
TAgileEncryptionVerifier KeyVerifier = new TAgileEncryptionVerifier();
TEncryptionParameters KeyEncParams = new TEncryptionParameters();
TAgileEncryptionKey KeyKey = new TAgileEncryptionKey();
using (MemoryStream ms = new MemoryStream(Enc))
{
using (XmlReader xml = XmlReader.Create(ms))
{
xml.ReadStartElement("encryption"); //goes to keyData
ReadAgileCipherParams(xml, DataEncParams, DataKey);
xml.ReadStartElement("keyData"); //goes to dataIntegrity
//We are not checking data integrity at the moment.
//DataIntegrity.EncryptedHMacKey = Convert.FromBase64String(xml.GetAttribute("encryptedHmacKey"));
//DataIntegrity.EncryptedHmacValue = Convert.FromBase64String(xml.GetAttribute("encryptedHmacValue"));
xml.ReadStartElement("dataIntegrity"); //goes to keyEncryptors
xml.ReadStartElement("keyEncryptors"); //goes to keyEncryptor
xml.ReadStartElement("keyEncryptor"); //goes to encryptedKey
KeyKey.SpinCount = Convert.ToInt32(xml.GetAttribute("spinCount"), CultureInfo.InvariantCulture);
ReadAgileCipherParams(xml, KeyEncParams, KeyKey);
KeyVerifier.EncryptedVerifierHashInput = Convert.FromBase64String(xml.GetAttribute("encryptedVerifierHashInput"));
KeyVerifier.EncryptedVerifierHashValue = Convert.FromBase64String(xml.GetAttribute("encryptedVerifierHashValue"));
KeyVerifier.EncryptedKeyValue = Convert.FromBase64String(xml.GetAttribute("encryptedKeyValue"));
}
}
CheckPassword(Encryption, KeyVerifier, KeyEncParams, KeyKey);
DataKey.Key = KeyKey.Key;
DataKey.Password = KeyKey.Password;
DataKey.CalcDataIV(0);
return(DecryptStream(DataStream, DataEncParams, DataKey));
}
private void ReadPropSectionHeader(TOle2File OleFile)
{
long PropStart = OleFile.Position;
byte[] PropSectionHeader = new byte[8];
OleFile.Read(PropSectionHeader, PropSectionHeader.Length);
int PropCount = (int)BitOps.GetWord(PropSectionHeader, 4);
TPropIdOffset[] PropOffsets = new TPropIdOffset[PropCount];
for (int i = 0; i < PropOffsets.Length; i++)
{
OleFile.Read(PropSectionHeader, 8); //Reuse the array to avoid allocate more memory
PropOffsets[i].Id = (UInt32)BitOps.GetInt32(PropSectionHeader, 0);
PropOffsets[i].Offset = (UInt32)BitOps.GetInt32(PropSectionHeader, 4);
}
Array.Sort(PropOffsets);
for (int i = 0; i < PropOffsets.Length; i++)
{
OleFile.SeekForward(PropOffsets[i].Offset + PropStart);
ReadProperty(OleFile, PropOffsets[i].Id);
}
//Get the actual codepage and convert the strings
int Cp = 1252; //windows western encoding.
object Cpo;
if (PropertyList.TryGetValue(1, out Cpo))
{
Cp = Convert.ToInt32(Cpo);
}
Encoding CodePage = Encoding.GetEncoding(Cp);
UInt32[] Keys = new UInt32[PropertyList.Count];
PropertyList.Keys.CopyTo(Keys, 0);
foreach (UInt32 key in Keys)
{
PropertyList[key] = ConvertStrings(PropertyList[key], CodePage);
}
}
internal static bool IsValidFile(Stream aStream)
{
using (TOle2File DataStream = new TOle2File(aStream, true))
{
if (DataStream.NotXls97)
{
return(false);
}
if (!DataStream.SelectStream(XlsxConsts.EncryptionInfoString, true))
{
return(false);
}
if (!DataStream.SelectStream(XlsxConsts.ContentString, true))
{
return(false);
}
}
return(true);
}
private void ReadProperty(TOle2File Ole2File, uint Id)
{
if (Id == 0) //This is the name list.
{
PropertyList.Add(Id, GetNameDictionary(Ole2File));
return;
}
byte[] PropTypeArray = new byte[4];
Ole2File.Read(PropTypeArray, PropTypeArray.Length);
Int32 PropType = BitOps.GetInt32(PropTypeArray, 0);
if (Id == 1 && PropType == (int)TPropertyTypes.VT_I2) //H a c k to get the correct codepage. It should not be negative.
{
PropType = (int)TPropertyTypes.VT_UI2;
}
object Value = GetOneProperty(Ole2File, PropType);
PropertyList.Add(Id, Value);
}
private static Stream ReadStandardEncryptionInfo(TOle2File DataStream, TEncryptionData Encryption)
{
byte[] RecordHeaderLen = new byte[4];
DataStream.Read(RecordHeaderLen, RecordHeaderLen.Length);
long EncryptionHeaderSize = BitOps.GetCardinal(RecordHeaderLen, 0);
byte[] EncryptionHeader = new byte[EncryptionHeaderSize];
DataStream.Read(EncryptionHeader, EncryptionHeader.Length);
long AlgId = BitOps.GetCardinal(EncryptionHeader, 8);
long KeyBits = BitOps.GetCardinal(EncryptionHeader, 16);
TEncryptionParameters EncParams = TEncryptionParameters.CreateStandard(GetStandardEncAlg(AlgId));
byte[] VerifierBytes = new byte[DataStream.Length - DataStream.Position];
DataStream.Read(VerifierBytes, VerifierBytes.Length);
TStandardEncryptionVerifier Verifier = ReadStandardVerifier(VerifierBytes);
TEncryptionKey Key = new TStandardEncryptionKey(ReadStandardSalt(VerifierBytes), (int)KeyBits / 8);
CheckPassword(Encryption, Verifier, EncParams, Key);
return(DecryptStream(DataStream, EncParams, Key));
}
internal void Write(TOle2File OleFile)
{
WriteHeader(OleFile);
}
private object GetOneProperty(TOle2File Ole2File, int PropType)
{
if ((PropType & (int)TPropertyTypes.VT_VECTOR) != 0)
{
byte[] i4 = new byte[4];
Ole2File.Read(i4, i4.Length);
object[] Vector = new object[BitOps.GetInt32(i4, 0)];
for (int i = 0; i < Vector.Length; i++)
{
Vector[i] = GetOneProperty(Ole2File, PropType & ~(int)TPropertyTypes.VT_VECTOR);
}
return(Vector);
}
switch ((TPropertyTypes)(PropType & 0xFF))
{
case TPropertyTypes.VT_EMPTY:
return(null);
case TPropertyTypes.VT_I2:
byte[] i2 = new byte[2];
Ole2File.Read(i2, i2.Length);
return(BitConverter.ToInt16(i2, 0));
case TPropertyTypes.VT_UI2: //This is not really suported, but we need to convert the CodePage to a Signed int.
byte[] ui2 = new byte[2];
Ole2File.Read(ui2, ui2.Length);
return((Int32)BitConverter.ToUInt16(ui2, 0));
case TPropertyTypes.VT_I4:
byte[] i4 = new byte[4];
Ole2File.Read(i4, i4.Length);
return(BitOps.GetInt32(i4, 0));
case TPropertyTypes.VT_R4:
byte[] d4 = new byte[4];
Ole2File.Read(d4, d4.Length);
return(BitConverter.ToSingle(d4, 0));
case TPropertyTypes.VT_R8:
byte[] d8 = new byte[8];
Ole2File.Read(d8, d8.Length);
return(BitConverter.ToDouble(d8, 0));
case TPropertyTypes.VT_CY:
byte[] cy = new byte[8];
Ole2File.Read(cy, cy.Length);
return(TCompactFramework.DecimalFromOACurrency(BitConverter.ToInt64(cy, 0)));
case TPropertyTypes.VT_DATE:
byte[] dd = new byte[8];
Ole2File.Read(dd, dd.Length);
DateTime Dt;
if (!FlxDateTime.TryFromOADate(BitConverter.ToDouble(dd, 0), false, out Dt))
{
return(DateTime.MinValue);
}
return(Dt.Date);
case TPropertyTypes.VT_BSTR:
byte[] sl = new byte[4];
Ole2File.Read(sl, sl.Length);
UInt32 StrLen = BitConverter.ToUInt32(sl, 0);
if (StrLen <= 1)
{
return(String.Empty); //StrLen includes the trailing #0
}
byte[] Str = new byte[StrLen - 1];
Ole2File.Read(Str, Str.Length);
Ole2File.SeekForward(Ole2File.Position + 1); //go over the 0 byte. This is needed for vectors/arrays.
return(new TUnconvertedString(Str, false));
case TPropertyTypes.VT_BOOL:
byte[] bl = new byte[2];
Ole2File.Read(bl, bl.Length);
return(BitConverter.ToInt16(bl, 0) == 0? false: true);
case TPropertyTypes.VT_VARIANT:
byte[] VariantTypeArray = new byte[4];
Ole2File.Read(VariantTypeArray, VariantTypeArray.Length);
Int32 VariantType = BitOps.GetInt32(VariantTypeArray, 0);
return(GetOneProperty(Ole2File, VariantType));
case TPropertyTypes.VT_I8:
byte[] i8 = new byte[8];
Ole2File.Read(i8, i8.Length);
return(BitConverter.ToInt64(i8, 0));
case TPropertyTypes.VT_LPSTR:
byte[] sl2 = new byte[4];
Ole2File.Read(sl2, sl2.Length);
UInt32 StrLen2 = BitConverter.ToUInt32(sl2, 0);
if (StrLen2 <= 1)
{
return(String.Empty); //StrLen includes the trailing #0
}
byte[] Str2 = new byte[StrLen2 - 1];
Ole2File.Read(Str2, Str2.Length);
Ole2File.SeekForward(Ole2File.Position + 1); //go over the 0 byte. This is needed for vectors/arrays.
return(new TUnconvertedString(Str2, false));
case TPropertyTypes.VT_LPWSTR:
byte[] sl3 = new byte[4];
Ole2File.Read(sl3, sl3.Length);
UInt32 StrLen3 = BitConverter.ToUInt32(sl3, 0);
if (StrLen3 <= 1)
{
return(String.Empty); //StrLen includes the trailing #0
}
byte[] Str3 = new byte[(StrLen3 - 1) * 2];
Ole2File.SeekForward(Ole2File.Position + 2); //go over the 0 byte. This is needed for vectors/arrays.
Ole2File.Read(Str3, Str3.Length);
return(new TUnconvertedString(Str3, true));
case TPropertyTypes.VT_FILETIME:
byte[] ft = new byte[8];
Ole2File.Read(ft, ft.Length);
return(DateTime.FromFileTime(BitConverter.ToInt64(ft, 0)));
case TPropertyTypes.VT_BLOB:
byte[] blb = new byte[4];
Ole2File.Read(blb, blb.Length);
UInt32 BlobLen = BitConverter.ToUInt32(blb, 0);
if (BlobLen <= 0)
{
return(new byte[0]); //BlobLen does not includes trailing #0
}
byte[] Blob = new byte[BlobLen];
Ole2File.Read(Blob, Blob.Length);
return(Blob);
}
return(null); //Not a supported type.
}
