// Compressed files start with an array of offsets to make seeking possible private void LoadBlockPositions() { int blockposcount = (int)((_entry.FileSize + _blockSize - 1) / _blockSize) + 1; // Files with metadata have an extra block containing block checksums if ((_entry.Flags & MpqFileFlags.FileHasMetadata) != 0) { blockposcount++; } _blockPositions = new uint[blockposcount]; lock (_stream) { _stream.Seek(_entry.FilePos, SeekOrigin.Begin); BinaryReader br = new BinaryReader(_stream); for (int i = 0; i < blockposcount; i++) { _blockPositions[i] = br.ReadUInt32(); } } uint blockpossize = (uint)blockposcount * 4; /* * if(_blockPositions[0] != blockpossize) * _entry.Flags |= MpqFileFlags.Encrypted; */ if (_entry.IsEncrypted) { if (_entry.EncryptionSeed == 0) // This should only happen when the file name is not known { _entry.EncryptionSeed = MpqArchive.DetectFileSeed(_blockPositions[0], _blockPositions[1], blockpossize) + 1; if (_entry.EncryptionSeed == 1) { throw new MpqParserException("Unable to determine encyption seed"); } } MpqArchive.DecryptBlock(_blockPositions, _entry.EncryptionSeed - 1); if (_blockPositions[0] != blockpossize) { throw new MpqParserException("Decryption failed"); } if (_blockPositions[1] > _blockSize + blockpossize) { throw new MpqParserException("Decryption failed"); } } }
private void LoadBlockPositions() { int num = ((int)(((this._entry.FileSize + this._blockSize) - 1) / ((long)this._blockSize))) + 1; if ((this._entry.Flags & MpqFileFlags.FileHasMetadata) != ((MpqFileFlags)0)) { num++; } this._blockPositions = new uint[num]; lock (this._stream) { this._stream.Seek((long)this._entry.FilePos, SeekOrigin.Begin); BinaryReader reader = new BinaryReader(this._stream); for (int i = 0; i < num; i++) { this._blockPositions[i] = reader.ReadUInt32(); } } uint decrypted = (uint)(num * 4); if (this._entry.IsEncrypted) { if (this._entry.EncryptionSeed == 0) { this._entry.EncryptionSeed = MpqArchive.DetectFileSeed(this._blockPositions[0], this._blockPositions[1], decrypted) + 1; if (this._entry.EncryptionSeed == 1) { throw new MpqParserException("Unable to determine encyption seed"); } } MpqArchive.DecryptBlock(this._blockPositions, this._entry.EncryptionSeed - 1); if (this._blockPositions[0] != decrypted) { throw new MpqParserException("Decryption failed"); } if (this._blockPositions[1] > (this._blockSize + decrypted)) { throw new MpqParserException("Decryption failed"); } } }