Difference between pages "Barnyard2" and "Chrome Disk Cache Format"

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(Created page with "==About == Barnyard is a critical tool for the parsing of Snort's unified binary files, processing and on-forwarding to a variety of output plugins. Unfortunately it has not s...")
 
 
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==About ==
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{{expand}}
Barnyard is a critical tool for the parsing of Snort's unified binary files, processing and on-forwarding to a variety of output plugins. Unfortunately it has not seen an updated in over 4 years and is not going to be maintained by the original developers. With the new version of the unified format (ie. unified2) arriving we need something to bridge this gap.
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To quote directly from the Snort FAQ:
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* "Barnyard is an output system for Snort. Snort creates a special binary output format called unified. Barnyard reads this file, and then resends the data to a database backend. Unlike the database output plug-in, Barnyard is aware of a failure to send the alert to the database, and it stops sending alerts. It is also aware when the database can accept connections again and will start sending the alerts again."
+
  
The SXL team love barnyard. So much so that we want it to stay and have been tinkering around with the code to give it a breath of new life. Here is what we have achieved to far for this reinvigorated code base:
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== Cache files ==
Parsing of the new unified2 log files.
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The cache is stored in multiple:
*Maintaining majority of the command syntax of barnyard.
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{| class="wikitable"
*Addressed all associated bug reports and feature requests arising since barnyard-0.2.0.
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|-
*Completely rewritten code based on the GPLv2 Snort making it entirely GPLv2.
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! Filename
 +
! Description
 +
|-
 +
| index
 +
| The index file
 +
|-
 +
| data_#
 +
| Data block files
 +
|-
 +
| f_######
 +
| (Separate) data stream file
 +
|}
  
== References ==
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== Cache address ==
All information on this page is referenced to [http://www.securixlive.com/barnyard2/about.php securixlive.com] where further information about Barnyard can be found.
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The cache address is 4 bytes in size and consists of:
 +
{| class="wikitable"
 +
|-
 +
! offset
 +
! size
 +
! value
 +
! description
 +
|-
 +
| <i>If file type is 0 (Separate file)</i>
 +
|
 +
|
 +
|
 +
|-
 +
| 0.0
 +
| 28 bits
 +
|
 +
| File number <br> The value represents the value of # in f_######
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|-
 +
| <i>Else</i>
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|
 +
|
 +
|
 +
|-
 +
| 0.0
 +
| 16 bits
 +
|
 +
| Block number
 +
|-
 +
| 2.0
 +
| 8 bits
 +
|
 +
| File number (or file selector) <br> The value represents the value of # in data_#
 +
|-
 +
| 3.0
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| 2 bits
 +
|
 +
| Block size <br> The number of contiguous blocks where 0 represents 1 block and 3 represents 4 blocks.
 +
|-
 +
| 3.2
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| 2 bits
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|
 +
| Reserved
 +
|-
 +
| <i>Common</i>
 +
|
 +
|
 +
|
 +
|-
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| 3.4
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| 3 bits
 +
|
 +
| File type
 +
|-
 +
| 3.7
 +
| 1 bit
 +
|
 +
| Initialized flag
 +
|}
 +
 
 +
=== File types ===
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{| class="wikitable"
 +
|-
 +
! Value
 +
! Description
 +
|-
 +
| 0
 +
| (Separate) data stream file
 +
|-
 +
| 1
 +
| (Rankings) block data file (36 byte block data file)
 +
|-
 +
| 2
 +
| 256 byte block data file
 +
|-
 +
| 3
 +
| 1024 byte block data file
 +
|-
 +
| 4
 +
| 4096 byte block data file
 +
|-
 +
|
 +
|
 +
|-
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| 6
 +
| Unknown; seen on Mac OS  X 0x6f430074
 +
|}
 +
 
 +
==== Examples ====
 +
{| class="wikitable"
 +
|-
 +
! Value
 +
! Description
 +
|-
 +
| 0x00000000
 +
| Not initialized
 +
|-
 +
| 0x8000002a
 +
| Data stream file: f_00002a
 +
|-
 +
| 0xa0010003
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| Block data file: data_1, block number 3, 1 block of size
 +
|}
 +
 
 +
== Index file format (index) ==
 +
Overview:
 +
* File header
 +
* least recently used (LRU) data (or eviction control data)
 +
* index table
 +
 
 +
=== File header ===
 +
*TODO*
 +
 
 +
== Data block file format (data_#) ==
 +
Overview:
 +
* File header
 +
* array of blocks
 +
 
 +
=== File header ===
 +
*TODO*
 +
 
 +
== Data stream ==
 +
See: [[gzip]]
 +
 
 +
== See Also ==
 +
* [[Google Chrome]]
 +
* [[gzip]]
 +
 
 +
== External Links ==
 +
* [http://www.chromium.org/developers/design-documents/network-stack/disk-cache Disk Cache], The Chromium Projects
 +
 
 +
[[Category:File Formats]]

Revision as of 03:43, 22 June 2014

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Please help to improve this article by expanding it.
Further information might be found on the discussion page.

Cache files

The cache is stored in multiple:

Filename Description
index The index file
data_# Data block files
f_###### (Separate) data stream file

Cache address

The cache address is 4 bytes in size and consists of:

offset size value description
If file type is 0 (Separate file)
0.0 28 bits File number
The value represents the value of # in f_######
Else
0.0 16 bits Block number
2.0 8 bits File number (or file selector)
The value represents the value of # in data_#
3.0 2 bits Block size
The number of contiguous blocks where 0 represents 1 block and 3 represents 4 blocks.
3.2 2 bits Reserved
Common
3.4 3 bits File type
3.7 1 bit Initialized flag

File types

Value Description
0 (Separate) data stream file
1 (Rankings) block data file (36 byte block data file)
2 256 byte block data file
3 1024 byte block data file
4 4096 byte block data file
6 Unknown; seen on Mac OS X 0x6f430074

Examples

Value Description
0x00000000 Not initialized
0x8000002a Data stream file: f_00002a
0xa0010003 Block data file: data_1, block number 3, 1 block of size

Index file format (index)

Overview:

  • File header
  • least recently used (LRU) data (or eviction control data)
  • index table

File header

  • TODO*

Data block file format (data_#)

Overview:

  • File header
  • array of blocks

File header

  • TODO*

Data stream

See: gzip

See Also

External Links