Snort mailing list archives
Re: File magic rules for 2.9.6, what options are required?
From: Joshua Kinard <kumba () gentoo org>
Date: Fri, 27 Dec 2013 15:11:09 -0500
On 12/27/2013 1:52 PM, Hui Cao wrote:
Hi Joshhua, Thanks for the great feedbacks. In general, file magic rule should be relative stable, so we just keep file magic rule syntax simple on this release. Please see my comments inline. Best, Hui. On 12/27/2013 12:10 PM, Joel Esler (jesler) wrote:This is great feedback. -- Joel Esler Intelligence Lead Open Source Manager Vulnerability Research Team Sent from my iPhone.On Dec 27, 2013, at 11:13, "Joshua Kinard" <kumba () gentoo org> wrote:On 12/26/2013 10:16 PM, Joel Esler (jesler) wrote: Thanks Joshua, one of the devels will get back to you.Couple of additional questions/ideas: - 'content' keyword should be a quoted string and optionally allow ASCII. I can see why the initial draft is to allow hexadecimal only, but one finds that a lot of file magics use printable ASCII. I.e., "%PDF-1." for PDF, "ELF" for Linux/Unix ELF executables, classic "MZ" for PE executables.Yes, this is a nice feature.
My other thought is this will match more closely the standard "content" keyword. Equally, that could get people confused by it...
Currently, category is used for document purpose. It can accept spaces.
Okay, I'll keep that note in mind. At least there's semi-colons to provide a hard delimiter between the keywords.
- ver: unquoted string, right? The source suggests such.Currently, ver is used for document purpose
This isn't used with the 'file_type' keyword at all? The documentation for that keyword only states that a value specified in file_type has to exist in a file magic definition, and I was assuming that "ver" was used to select a specific file magic rule. E.g., Given these file magic rules: file type:PDF; id:42; ver:1.4; group:pdf; msg:"PDF v1.4"; content:|25 50 44 46 2d 31 2e 34|; rev:1; file type:PDF; id:43; ver:1.5; group:pdf; msg:"PDF v1.5"; content:|25 50 44 46 2d 31 2e 35|; rev:1; Then, "file_type:PDF,1.5;" would match the second one? --J ------------------------------------------------------------------------------ Rapidly troubleshoot problems before they affect your business. Most IT organizations don't have a clear picture of how application performance affects their revenue. With AppDynamics, you get 100% visibility into your Java,.NET, & PHP application. Start your 15-day FREE TRIAL of AppDynamics Pro! http://pubads.g.doubleclick.net/gampad/clk?id=84349831&iu=/4140/ostg.clktrk _______________________________________________ Snort-devel mailing list Snort-devel () lists sourceforge net https://lists.sourceforge.net/lists/listinfo/snort-devel Archive: http://sourceforge.net/mailarchive/forum.php?forum_name=snort-devel Please visit http://blog.snort.org for the latest news about Snort!
Current thread:
- File magic rules for 2.9.6, what options are required? Joshua Kinard (Dec 26)
- Re: File magic rules for 2.9.6, what options are required? Joel Esler (jesler) (Dec 26)
- Re: File magic rules for 2.9.6, what options are required? Joshua Kinard (Dec 27)
- Re: File magic rules for 2.9.6, what options are required? Joshua Kinard (Dec 27)
- Re: File magic rules for 2.9.6, what options are required? Joel Esler (jesler) (Dec 27)
- Re: File magic rules for 2.9.6, what options are required? Hui Cao (Dec 27)
- Re: File magic rules for 2.9.6, what options are required? Joshua Kinard (Dec 27)
- Re: File magic rules for 2.9.6, what options are required? Joshua Kinard (Dec 27)
- Re: File magic rules for 2.9.6, what options are required? Victor Roemer (Dec 27)
- Re: File magic rules for 2.9.6, what options are required? Joshua Kinard (Dec 27)
- Re: File magic rules for 2.9.6, what options are required? Joel Esler (jesler) (Dec 26)