l i n u x - u s e r s - g r o u p - o f - d a v i s
Next Meeting:
July 7: Social gathering
Next Installfest:
Latest News:
Jun. 14: June LUGOD meeting cancelled
Page last updated:
2004 Jan 29 15:50

The following is an archive of a post made to our 'vox-tech mailing list' by one of its subscribers.

Report this post as spam:

(Enter your email address)
Re: [vox-tech] Virus deluge
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [vox-tech] Virus deluge

on Tue, Jan 27, 2004 at 10:39:17PM -0800, Mark K. Kim (markslist@cbreak.org) wrote:
> On Tue, 27 Jan 2004, Karsten M. Self wrote:
> > > ================================================================================
> > > :0 B
> > > * -1
> > > * 1^0 ^Content-Transfer-Encoding: base64
> > > * 1^0 1rrAeM0gDQdlmmtNtWVfG3QRFA672grQLlgIdDhobVVL2XMWVlc87bWFzho6IHtwAj2d9r
> > > * 1^0 Ga9SG/3//7dSpCoQS7DvKZAv72JQKWmvdKWWbadVD/D//9vSfeg2mRbgbKcMvEZXguXrNq
> > > * 1^0 TBuvVXOm//9/idxR1/7/Y6uPvh3LTd755dO39hzsPp/6sfv///8xZXpCOlu2J40AUMvgDP
> > > * 1^0 Q2VDAuk6pQf8sthCvHkbFDMACWK8hd0C2mSZPSKSIjutcMMWTmfwLUdsuyF4o1Tjemh5hk
> > > * 1^0 Z3h2Z0tDwwdp3y78fy10dmV5LTIuMG9xcIxfY05wdXJmmaHdCjNcdmkLRDvZ1r5tSGRWLV
> > > * 1^0 V0jTDPIH0MgIsEjTDDKYiAqARYEDNnhPUmWtFnAb4JuraGYHK2nGAwbeAiBFcj2UWskGOE
> > > {
> > >     LOG="LOG: Virus: (Mydoom / Novar)"
> > >
> > >     :0:
> > >     Virus/
> > > }
> > > ================================================================================
> I'm new to procmail so can I ask some questions?
> What do ":0 B", "-1", and "1^0" do?  Does LOG do anything?

Peter got most of this.

:<number> starts a recipie.  Used to be that <number> was (IIRC) the
number of lines in the recipie.  Now it's typically set to 0, and has no
special significance.

'B' scans body

: *after* '0' indicates a lockfile.  Any rule that writes to a file
    _should_ use a lockfile.  Rules which invoke a program '| command'
    or delivery '! address' _don't_ need a lockfile.

For more information:  man procmail; man procmailrc; man procmailex

* <number>
* <number>^<number>

...are scoring rules.  The first number says what to add.  The
second says when to add it, and by how much.  I understand this only


  - No trailing value means "apply this score once in the evaluation of
    this recipie".

  - A trailing '0' means "apply this score once and only once if it is

  - A trialing '1' means "add the score for *each* occurance of a match.

  - 0 <x<1 : Each successive match contributes less than the prior one.
             The score asymptotically approaches a value.

  - 1 < x  : Each successive match contributes more than the prior one.
             The score grows asymptotically.

For more information:  man procmailsc

The rule says, in English:

  - Start a recipie. Scan the body.
  - Use scoring.  Set a default score of '-1' (require two matches for
    the rule to take effect)
  - Add one for a base64 MIME encoding demarcation.
  - Add one for any of the following legacy MS Windows executable
  - The condition in braces is met if two rules matched.
  - (If logging) log that this was a MyDoom virus match.
  - Write to the Virus folder, a Maildir directory (the trailing '/'

> Thanks!  The rules seem to be working so far...



Karsten M. Self <kmself@ix.netcom.com>        http://kmself.home.netcom.com/
 What Part of "Gestalt" don't you understand?
   Sick of mal-formed websites?  A stylesheet to override poor design:

Attachment: signature.asc
Description: Digital signature

LUGOD Group on LinkedIn
Sign up for LUGOD event announcements
Your email address:
LUGOD Group on Facebook
'Like' LUGOD on Facebook:

Hosting provided by:
Sunset Systems
Sunset Systems offers preconfigured Linux systems, remote system administration and custom software development.

LUGOD: Linux Users' Group of Davis
PO Box 2082, Davis, CA 95617
Contact Us

LUGOD is a 501(c)7 non-profit organization
based in Davis, California
and serving the Sacramento area.
"Linux" is a trademark of Linus Torvalds.

Sponsored in part by:
Sunset Systems
Who graciously hosts our website & mailing lists!