linux-kernel - Re: JFFS2 using 'private' zlib header (was [RFC] LZO de/compression support

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <172CB60C-2F1F-4CCE-8AB7-C7CFA1161AA0@alumni.caltech.edu>
Date:	Tue, 29 May 2007 22:31:19 -0700
From:	Mark Adler <madler@...mni.caltech.edu>
To:	Satyam Sharma <satyam.sharma@...il.com>
Cc:	"Daniel Hazelton" <dhazelton@...er.net>,
	"Michael-Luke Jones" <mlj28@....ac.uk>,
	lkml <linux-kernel@...r.kernel.org>, dwmw2@...radead.org,
	jloup@...p.org
Subject: Re: JFFS2 using 'private' zlib header (was [RFC] LZO de/compression support - take 6)

On May 29, 2007, at 8:15 AM, Satyam Sharma wrote:
> skipping some checksum calculation if some
> flag (PRESET_DICT) is absent from the input stream about to
> be decompressed ...

You don't need to dissect the header manually to look for that bit.   
If you feed inflate() at least the first two bytes, it will return  
immediately with the Z_NEED_DICT return code if a preset dictionary  
is requested.  You can force inflate() to return immediately after  
decoding the two byte header even if a preset dictionary is not  
requested by using the Z_BLOCK flush code.

Mark

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/