Re: 128 bits extent bmap for file format 2

[Pradeep Kumar <praks411@xxxxxxxxx>]

Hi Greg,

This could be nice addition. I will try to submit it once done.

Pradeep

On 22 October 2013 15:11, Greg Freemyer <greg.freemyer@xxxxxxxxx> wrote:

Pradeep Kumar <praks411@xxxxxxxxx> wrote:
>Hi,
>
>I'm writing a small utility to parse XFS fs image on windows.
>I'm able to fetch the files in the first AG (0).
>However when it comes to the files which are in different AG I'm facing
>some problem in parsing extent bmap 128bits data of file inode (format
>==
>2).
>
>Here is the sample 128bits data
>1. 00 00 00 00 00 00 00 00 00 00 00 04 99 80 00 01 (LSB)
>
>After unpacking the bits are per doc and source code
>In the above case I'm getting following
>Num Of blocks = 1 (correct) (0 to 20 bits)
>absolute block number = 9420 (0x24CC) (wrong) (21 to 72)
>file offset = 0 (72 to 126)
>
>I'm always getting wrong absolute block number . Actual data is in
>block
>7628 (0x1DCC).
>No matter what I try I'm always getting the same result. I've even
>verified
>this
>by using the code from xfs_bmbt_get_all function from xfs source which
>too
>gives me same result (9420).
>Please someone help me with this. I'm stuck on this from 3 days.
>
>Thanks and Regards,
>Pradeep

Pradeep,

It would be cool if your utility could be incorporated into sleuthkit.  Sleuthkit has fat and NTFS parsers for sure already.  I think ext2 and ext3.  Adding a xfs parser would be a cool addition.

 http://www.sleuthkit.org/sleuthkit/docs/api-docs/index.html#users_guide

Fyi: sleuthkit has been around for a long time, but it is still actively maintained and heavily used.  It is in several linux distros, but is also available for windows.

Greg
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