复合二进制文档

复合二进制文档（CFBF），簡称复合文档，英文全名 Composite Document File V2 Document，是微软开发、用於实现COM结构化存储的文件格式，用于把多个对象内容存放在同一个硬盘文件。 Microsoft已经开放了这个文件格式。广泛用于Microsoft Word与Microsoft Access。也是Advanced Authoring Format（英语：Advanced Authoring Format）的基础。 CFBF文件头部是512字节，随后跟着是保存数据的扇区。扇区的长度在文件头部指定，通常是512字节或4096字节。 CFBF的扇区类型: FAT扇区 MiniFAT扇区：用于Mini-Stream Double-Indirect FAT （DIFAT）扇区 - 包含FAT扇区索引的链表数据 Directory扇区 Stream扇区 - 包含数据内容 Range Lock扇区 - 包含大文件的上锁的字节范围 CFBF头是该文件的最前的512字节。对应于C语言数据结构为： typedef unsigned long ULONG; // 4 Bytes typedef unsigned short USHORT; // 2 Bytes typedef short OFFSET; // 2 Bytes typedef ULONG SECT; // 4 Bytes typedef ULONG FSINDEX; // 4 Bytes typedef USHORT FSOFFSET; // 2 Bytes typedef USHORT WCHAR; // 2 Bytes typedef ULONG DFSIGNATURE; // 4 Bytes typedef unsigned char BYTE; // 1 Byte typedef unsigned short WORD; // 2 Bytes typedef unsigned long DWORD; // 4 Bytes typedef ULONG SID; // 4 Bytes typedef GUID CLSID; // 16 Bytes struct StructuredStorageHeader { // [offset from start (bytes), length (bytes)] BYTE _abSig[8]; // [00H,08] {0xd0, 0xcf, 0x11, 0xe0, 0xa1, 0xb1, // 0x1a, 0xe1} for current version CLSID _clsid; // [08H,16] reserved must be zero (WriteClassStg/ // GetClassFile uses root directory class id) USHORT _uMinorVersion; // [18H,02] minor version of the format: 33 is // written by reference implementation USHORT _uDllVersion; // [1AH,02] major version of the dll/format: 3 for // 512-byte sectors, 4 for 4 KB sectors USHORT _uByteOrder; // [1CH,02] 0xFFFE: indicates Intel byte-ordering USHORT _uSectorShift; // [1EH,02] size of sectors in power-of-two; // typically 9 indicating 512-byte sectors USHORT _uMiniSectorShift; // [20H,02] size of mini-sectors in power-of-two; // typically 6 indicating 64-byte mini-sectors USHORT _usReserved; // [22H,02] reserved, must be zero ULONG _ulReserved1; // [24H,04] reserved, must be zero FSINDEX _csectDir; // [28H,04] must be zero for 512-byte sectors, // number of SECTs in directory chain for 4 KB // sectors FSINDEX _csectFat; // [2CH,04] number of SECTs in the FAT chain SECT _sectDirStart; // [30H,04] first SECT in the directory chain DFSIGNATURE _signature; // [34H,04] signature used for transactions; must // be zero. The reference implementation // does not support transactions ULONG _ulMiniSectorCutoff; // [38H,04] maximum size for a mini stream; // typically 4096 bytes SECT _sectMiniFatStart; // [3CH,04] first SECT in the MiniFAT chain FSINDEX _csectMiniFat; // [40H,04] number of SECTs in the MiniFAT chain SECT _sectDifStart; // [44H,04] first SECT in the DIFAT chain FSINDEX _csectDif; // [48H,04] number of SECTs in the DIFAT chain SECT _sectFat[109]; // [4CH,436] the SECTs of first 109 FAT sectors }; 每个FAT条目长度4字节，包含下个FAT链表条目的扇区号，或下述特定值： FREESECT (0xFFFFFFFF) - 未用扇区 ENDOFCHAIN (0xFFFFFFFE) - FAT链表最后一个扇区 FATSECT (0xFFFFFFFD) - 用于FAT数据存储 DIFSECT (0xFFFFFFFC) - 用于DIFAT数据存储 FAT - 文件分配表，也称 SAT - 扇区分配表 DIFAT - Double-Indirect File Allocation Table FAT Chain - 一群FAT条目指出分配给一个流的那些扇区 Stream - 一个数据对象的内容 Sector - 扇区，占据512或4096个字节 COM结构化存储 Apache POI - POIFS. POI Project. [10 May 2011]. （原始内容存档于2011-04-26）.  How to convert documents between LibreOffice and Microsoft Office file formats on Linux. [25 Nov 2016]. （原始内容存档于2019-09-21）.  Compound Files (Windows). Microsoft Developers Network (MSDN) library – COM SDK. Microsoft Corporation. 20 November 2008 [23 September 2009]. （原始内容存档于2016-03-07）.  Containers: Compound Files. Microsoft Developers Network (MSDN) library – Visual Studio 2008 documentation. Microsoft Corporation. [23 September 2009]. （原始内容存档于2012-10-18）.  Understand Compound Files. Microsoft Developers Network (MSDN) library – ActiveDirectory Rights Management. 25 June 2009 [23 September 2009]. （原始内容存档于2016-03-09）.  AMW Association (formerly AAF Association) 互联网档案馆的存檔，存档日期15 August 2000. Microsoft Compound Document File Format (PDF). OpenOffice.org CFBF description. [2006-05-22]. （原始内容存档 (PDF)于2011-10-12）.  Advanced Authoring Format Low-Level Container Specification (PDF). Microsoft Structured Storage version 3 specification (PDF). [2006-05-22]. （原始内容 (PDF)存档于2011-08-09）.