词汇

Concept - File

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Overview

It is composed of attributes including its name and its data.

Attributes

Type Description Name
0x10 $STANDARD_INFORMATION  
0x30 $FILE_NAME filename
0x50 $SECURITY_DESCRIPTOR  
0x80 $DATA [Unnamed]

Standard Information

This contains the DOS-style file permission, such as read-only and archive. It also contains four different types of modification time.

File Name

The file's name is stored as an attribute, too. A file can have several filenames. This is Windows' equivalent to hard linking files together.

Security Descriptor

This stores all of Windows' permissions. ACLs, ACEs, auditing.

    May not exist on Win2K (std info, $secure)
    

Data

This, finally, is the actual data of the file. It, too, is stored in an attribute

    unnamed data stream compulsory (chkdsk will put it back if missing)
    named data streams optional (any limit to the number?)
    

Named Data Streams

    access with "jim.txt:stream"
    
Type Description Name
0x80 $DATA icon
0x80 $DATA author

Summary Information

Windows 2000 introduced the idea of summary information on files. This information is stored as a set of four named data streams.

Description
Title
Subject
Category
Keywords (multi-line)
Comments (multi-line)
Origin
Source
Author
Revision Number
Type Description Name
0x80 $DATA {4c8cc155-6c1e-11d1-8e41-00c04fb9386d}
0x80 $DATA ^EDocumentSummaryInformation
0x80 $DATA ^ESebiesnrMkudrfcoIaamtykdDa
0x80 $DATA ^ESummaryInformation

N.B. Three of the names begin with CTRL-E (0x05). This is probably to discourage people from reading the streams directly.

The first stream {4c.. is always empty. This is probably just a marker to

Data Stream Summary Field Data Type Code
^EDocumentSummaryInformation Unknown1 Numeric? 0x00
Unknown2 Numeric 0x01
Category ASCII 0x02
^ESebiesnrMkudrfcoIaamtykdDa Unknown3 Numeric? 0x00
Unknown4 Numeric? 0x01
Source Unicode 0x04
^ESummaryInformation Unknown5 Numeric? 0x00
Unknown6 Numeric? 0x01
Title ASCII 0x02
Subject ASCII 0x03
Author ASCII 0x04
Keywords ASCII 0x05
Comments ASCII 0x06
Revision Number ASCII 0x09

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