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From: Kenji Arisawa <arisawa@ar.aichi-u.ac.jp>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
Subject: Re: [9fans] (no subject)
Date: Sat, 22 Nov 2008 06:33:25 +0900	[thread overview]
Message-ID: <A94D35CE-A3CD-4D8F-902F-FB7D214A55AA@ar.aichi-u.ac.jp> (raw)
In-Reply-To: <91428b31c1ef98ddc01e31bf249b0b7a@quanstro.net>

Hello,

If such an attack continues for some minutes and the server does not
reject the connections
the server will create thousands of smtpd processes and might be hung
up.

Kenji Arisawa

On 2008/11/22, at 3:28, erik quanstrom wrote:

> Subjet: email attacks
>
> since our friends in sweeden helped out our spammer friends
> get back on line, i've seen a lot more attacks.  today i've been
> getting ~10 connections/sec.  fortunately its from a small
> number of machines, so this trick helps alot:
>
> /n/dump/2008/1121/sys/src/cmd/upas/smtp/smtpd.c:348,353 - smtpd.c:
> 348,355
>   				if(!qflag)
>   					syslog(0, "smtpd", "Hung up on %s; "
>   						"claimed to be %s", nci->rsys, him);
> + 				if(Dflag)
> + 					sleep(delaysecs()*1000);
>   				reply("554 5.7.0 Liar!\r\n");
>   				exits("client pretended to be us");
>   				return;
>
> oddly, i've found that adding a few of the hosts as -k flags stops
> the attack
> entirely.
>
> - erik
>
>




  reply	other threads:[~2008-11-21 21:33 UTC|newest]

Thread overview: 433+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-11-21 18:28 erik quanstrom
2008-11-21 21:33 ` Kenji Arisawa [this message]
2008-11-21 22:55   ` erik quanstrom
  -- strict thread matches above, loose matches on Subject: below --
2018-04-02 15:27 Steve Simon
2018-04-02 21:08 ` Digby R.S. Tarvin
2018-01-04 20:11 Steve Simon
2018-01-04 20:22 ` Lyndon Nerenberg
2018-01-04 21:20   ` Steve Simon
2018-01-04 22:27     ` Joseph Stewart
2018-01-04 23:22       ` Rob Pike
2018-01-04 23:37 ` Greg Lewin
2017-08-30 14:12 Steve Simon
2017-08-30 16:36 ` Steven Stallion
2016-12-02 11:44 Steve Simon
2016-12-02 19:12 ` Bakul Shah
2016-07-29  0:01 kokamoto
2014-11-25  4:20 trebol
2014-07-31  5:18 kokamoto
2014-07-05  0:38 kokamoto
2014-06-21 19:45 Steve Simon
2014-06-21 23:39 ` cinap_lenrek
2014-06-22  6:54   ` Steve Simon
2014-04-16  1:52 sl
2014-04-16  9:39 ` Ingo Krabbe
2014-04-15 14:41 Steve Simon
2014-04-15 15:36 ` Anthony Sorace
2014-04-15 18:18   ` sl
2014-04-15 22:42     ` erik quanstrom
2014-04-15 23:40       ` arisawa
2014-04-16  1:20     ` Anthony Sorace
2014-04-15 15:50 ` erik quanstrom
2014-04-15 17:46   ` Aram Hăvărneanu
2014-04-15 17:53     ` erik quanstrom
2014-03-19 18:44 Jacob Todd
2014-03-15 23:07 Steve Simon
2014-03-15 23:26 ` Jacob Todd
2014-03-16 14:51   ` erik quanstrom
2014-03-16  1:51 ` Jeff Sickel
2013-11-17 23:04 Steve Simon
2013-06-03 15:43 sl
2013-04-30 15:56 lucio
2013-04-30 17:11 ` erik quanstrom
2012-10-19  9:46 Sophit4
2012-09-03 11:16 yaroslav
2012-09-03 11:40 ` Charles Forsyth
2012-04-11  9:38 陈俊秀
2011-12-30 18:08 erik quanstrom, erik quanstrom
2011-12-30 18:49 ` Jack Norton
2011-12-30 19:24   ` erik quanstrom
2011-12-30 20:35 ` Aram Hăvărneanu
2011-12-30 21:28   ` Bakul Shah
2011-12-30 21:34     ` Charles Forsyth
2011-12-30 21:38       ` Aram Hăvărneanu
2011-12-30 21:53       ` Bakul Shah
2011-12-30 21:56         ` Aram Hăvărneanu
2011-12-30 22:41           ` Charles Forsyth
2011-12-30 23:00             ` Lyndon Nerenberg
     [not found] ` <CAEAzY38puVSzEnn90mmi+Bq4hnL9WpbBsnysjJYvXYw3xvE=xA@mail.gmail.c>
2011-12-30 21:05   ` erik quanstrom
2011-12-30 21:39     ` Jack Norton
2011-12-31  5:31       ` erik quanstrom
2011-12-31 17:40         ` Aram Hăvărneanu
     [not found]         ` <CAEAzY39S9z6mKtun68DGFbEkA6y8kaqTEyDCkW6ydHK8aHFG5A@mail.gmail.c>
2011-12-31 19:32           ` erik quanstrom
2012-01-05 18:03             ` Aram Hăvărneanu
2011-11-22 18:32 Steve Simon
2011-08-09 12:40 Steve Simon
2011-08-09 12:54 ` erik quanstrom
2011-08-09 13:07   ` Steve Simon
2011-08-09 14:52     ` erik quanstrom
2011-08-09 18:21     ` Lyndon Nerenberg (VE6BBM/VE7TFX)
2011-08-09 18:31       ` Steve Simon
2011-08-09 14:12 ` Russ Cox
2011-04-06  9:09 Stanley Lieber
2011-04-25  7:42 ` Steve Simon
2011-04-25 13:11   ` erik quanstrom
     [not found] <96cc26fe3002748983b3fc16cc949bab@quintile.net>
2011-03-28 13:56 ` erik quanstrom
2011-03-28 14:50   ` cinap_lenrek at gmx.de
2011-03-28 15:18     ` ron minnich
2011-03-28 22:57       ` erik quanstrom
2010-12-21  3:43 erik quanstrom, erik quanstrom
2010-05-06 19:55 erik quanstrom
2010-03-08  4:22 lucio
2010-03-08  4:49 ` ron minnich
2010-03-08  4:58   ` lucio
2010-03-08  6:17     ` Russ Cox
2010-03-08  6:22       ` lucio
2010-03-08 15:13     ` Patrick Kelly
2010-03-08 15:57       ` Francisco J Ballesteros
2010-03-08  8:54 ` Richard Miller
2010-03-08  9:31   ` lucio
2010-03-08 22:53 ` Sascha Retzki
2010-03-08 18:01   ` lucio
2010-03-08 19:20     ` Lyndon Nerenberg (VE6BBM/VE7TFX)
2010-03-09  4:20       ` lucio
2010-03-09  5:26         ` Lyndon Nerenberg (VE6BBM/VE7TFX)
2010-03-09  5:32           ` erik quanstrom
2010-03-09  5:50             ` Lyndon Nerenberg (VE6BBM/VE7TFX)
2010-03-09 20:08               ` Patrick Kelly
2010-03-08 19:41     ` erik quanstrom
2010-03-08 22:19     ` James Tomaschke
2010-03-09  4:34       ` lucio
     [not found] <mailman.26991.1268008023.1512.9fans@9fans.net>
2010-03-08  0:54 ` - Choc -
2010-03-07 17:47 lucio
2010-03-07 18:37 ` John Floren
2010-03-07 19:16   ` lucio
2010-03-07 19:57     ` erik quanstrom
2010-03-08  4:29       ` lucio
2010-03-06  9:32 [9fans] nb—search and index notes in files by keyword Peter A. Cejchan
2010-03-07  4:30 ` [9fans] (no subject) lucio
2010-03-07  5:05   ` Anthony Sorace
2010-03-07 17:31     ` ron minnich
2010-03-07 17:43       ` erik quanstrom
2010-03-07 18:14         ` lucio
2010-03-07 19:25           ` cinap_lenrek
2010-03-07 17:42     ` lucio
2010-03-07 17:53       ` erik quanstrom
2010-03-07 18:06         ` lucio
2010-03-07 18:59       ` Iruata Souza
2010-03-07 19:26         ` lucio
2010-03-07 19:36           ` ron minnich
2010-03-07  9:14   ` Skip Tavakkolian
2010-03-07 11:04     ` lucio
2010-02-05  1:53 erik quanstrom
2010-01-18 21:55 erik quanstrom
2009-09-29 23:25 [9fans] acme without a heavy grid (SFW) Jason Catena
2009-10-01 16:49 ` J.R. Mauro
2009-10-01 17:18   ` [9fans] (no subject) Pablo Alonso Salas Alvarez
2009-09-15 22:34 erik quanstrom
2009-07-24 17:18 erik quanstrom
2009-07-24 17:20 ` erik quanstrom
2009-07-24 16:14 [9fans] Does "as little software as possible" include a modern maht
2009-07-24 17:16 ` [9fans] (no subject) erik quanstrom
2009-07-17 21:09 drivers
2009-05-28 11:08 Gregory Pavelcak
2009-04-23 11:38 Steve Simon
2009-04-23 12:34 ` Charles Forsyth
2009-04-23 13:07   ` Devon H. O'Dell
2009-04-23 17:13   ` lucio
2009-04-23 17:17     ` erik quanstrom
2009-04-23 17:28       ` David Leimbach
2009-04-23 19:32 ` lucio
2009-04-27  4:42 ` lucio
2009-04-27 11:57   ` lucio
2009-04-27 21:30   ` Steve Simon
2009-02-24  0:29 mattmobile
2009-02-24  0:48 ` ron minnich
2009-02-24  1:02   ` Jeff Sickel
2009-02-24  1:25     ` sixforty
2009-02-24  2:13       ` Anthony Sorace
2009-02-23  0:13 [9fans] actionfs mattmobile
2009-03-05 13:16 ` [9fans] (no subject) cej
2009-01-02  2:30 erik quanstrom
2008-12-06 19:28 Dave Eckhardt
2008-12-06 23:42 ` Roman Shaposhnik
2008-12-07  0:04   ` erik quanstrom
2008-08-14 19:09 akumar
2008-08-14 19:14 ` andrey mirtchovski
2008-07-19  2:37 [9fans] 9vx and local file systems Russ Cox
2008-07-21 13:26 ` [9fans] (no subject) kokamoto
2008-07-21 14:45   ` a
2008-03-19  5:03 Skip Tavakkolian
2008-03-19 12:41 ` erik quanstrom
2008-03-19 17:16   ` Lyndon Nerenberg
2007-12-14 23:02 Joshua Wood
2007-11-15 20:00 erik quanstrom
2007-08-24  1:54 YAMANASHI Takeshi
2007-08-24  2:04 ` erik quanstrom
2007-07-08 12:37 Gregory Pavelcak
2007-07-08 14:08 ` erik quanstrom
2007-07-08 14:50   ` erik quanstrom
2007-07-12 20:57     ` erik quanstrom
2007-05-25 23:29 ozan s. yigit
2007-05-25 23:42 ` Charles Forsyth
2007-05-26  0:09   ` ozan s. yigit
2007-05-28 12:36   ` Lluís Batlle
2007-05-11  6:57 Lyndon Nerenberg
2007-05-08 23:02 Steve Simon
2007-04-13 22:16 devon.odell
2007-04-14 11:17 ` W B Hacker
2007-01-15 23:24 steve
2006-12-12 21:20 Steve Simon
2006-12-10 13:49 sape
2006-09-13  7:28 Aw: " chuckf
2006-09-13  7:55 ` Sascha Retzki
2006-09-12 20:44 Chuck Foreman
2006-09-12 20:47 ` David Hendricks
2006-09-12 20:55 ` Federico Benavento
2006-09-02 11:16 lucio
2006-09-02 17:49 ` Gorka guardiola
2006-09-02 18:38   ` Gorka guardiola
2006-09-03  5:46     ` geoff
2006-09-03 10:51       ` Álvaro Jurado Cuevas
2006-08-21 12:43 Steve Simon
2006-08-22 17:56 ` Sergey Zhilkin
2006-04-21  4:09 Rafeek Raja
2006-02-10 15:30 quanstro
2006-02-10 14:10 quanstro
2006-02-10 15:17 ` jmk
2006-02-07 17:09 Riza Dindir
2005-09-09 18:46 Fco. J. Ballesteros
2005-08-07 22:24 Steve Simon
2005-08-08 13:25 ` Sape Mullender
2005-05-31  3:53 焕宇 苏
2005-05-30 19:01 quanstro
2005-02-10 15:28 tapique
2005-02-11 18:12 ` Bruce Ellis
2004-12-14 20:33 Charles Forsyth
2004-12-14 21:02 ` Bruce Ellis
2004-12-14 21:19 ` Ronald G. Minnich
2004-12-14 21:33   ` boyd, rounin
2004-12-14 21:38   ` Charles Forsyth
2004-12-14 22:01     ` Ronald G. Minnich
2004-12-14 22:12       ` andrey mirtchovski
2004-12-14 22:25         ` Ronald G. Minnich
2004-12-14 22:16       ` Charles Forsyth
2004-12-14 22:26         ` Ronald G. Minnich
2004-12-14 22:26           ` boyd, rounin
2004-12-14 22:36             ` jim
2004-12-14 22:48               ` Dan Cross
2004-12-14 22:47                 ` boyd, rounin
2004-12-14 23:00                 ` jim
2004-12-14 23:07                   ` boyd, rounin
2004-12-14 23:27                   ` Dan Cross
2004-12-14 22:50               ` Brantley Coile
2004-12-14 23:08                 ` jim
2004-12-14 23:12                   ` Brantley Coile
2004-12-14 22:55               ` andrey mirtchovski
2004-12-14 23:35               ` Ronald G. Minnich
2004-12-14 23:35                 ` boyd, rounin
2004-12-14 23:41                 ` andrey mirtchovski
2004-12-01 10:57 Steve Simon
2004-12-01 11:03 ` Tiit Lankots
2004-12-01 18:37 ` Jack Johnson
2004-12-01 18:47   ` Christopher Nielsen
2004-11-09 13:28 cej
2004-07-28  2:10 YAMANASHI Takeshi
2004-07-27  9:08 Steve Simon
2004-07-27  9:38 ` Kenji Okamoto
2004-07-27  9:44   ` Lucio De Re
2004-07-27 10:54   ` Steve Simon
2004-07-27 13:36     ` Boris Maryshev
2004-07-27 15:23       ` Justin Herald
2004-07-27 19:55     ` Francisco Ballesteros
2004-07-27 20:22     ` Skip Tavakkolian
2004-07-28  4:08     ` Dan Cross
2004-07-28  4:39       ` Justin Herald
2004-07-26 17:59 steve
2004-07-26 17:48 The Post Office
2004-07-26 17:30 join-jibjab
2004-07-26 17:18 melinda.proost
2004-07-26 16:58 Mail Delivery Subsystem
2004-07-26 16:21 swe
2004-07-26 16:06 library
2004-07-26 15:59 justin.jaffe
2004-07-26 15:44 The Post Office
2004-07-26 15:25 andrewm
2004-07-26 15:20 Automatic Email Delivery Software
2004-07-26 15:14 newswire
2004-07-19  8:17 judge
2004-07-16 11:38 Chris
2004-07-15  3:46 Michelle
2004-07-13 15:19 Fco. J. Ballesteros
2004-07-09 17:25 Steven
2004-07-07  1:49 Pam Moran
2004-07-03 22:23 Joseph
2004-07-02 12:05 Don
2004-06-28 12:49 Steve Simon
2004-06-22 20:43 Pete
2004-05-17 15:50 matt lawless
2004-05-18  8:31 ` john grove
2004-05-19  8:31 ` john grove
2004-04-19  8:29 Steve Simon
2004-04-13 11:54 matt
2004-04-13 21:25 ` Geoff Collyer
2004-04-13 21:28   ` boyd, rounin
2004-03-23 16:12 David Presotto
2004-03-04 17:57 David Presotto
2004-03-04 18:12 ` Charles Forsyth
2004-03-04 18:21   ` Dave Lukes
2004-03-04 18:29     ` Charles Forsyth
2004-03-04 22:21     ` boyd, rounin
2004-02-22 20:07 Russ Cox
2004-02-17 14:26 David Presotto
2004-02-17 16:13 ` Rob Pike
2004-02-17 16:17   ` David Presotto
2004-02-17 16:29     ` Rob Pike
2004-02-18  3:52   ` boyd, rounin
2004-02-17 21:25 ` C H Forsyth
2004-02-17 23:57 ` Charles Forsyth
2004-02-18  0:03   ` David Presotto
2004-02-18  6:58   ` 9nut
2004-02-18 16:56   ` rog
2004-02-01  0:34 sam
2004-01-30 18:10 engineering
2004-01-27 12:47 ravi
2004-01-22 15:22 Sape Mullender
2003-12-11 21:38 David Presotto
2003-11-25 15:18 Steve Simon
2003-11-02 21:12 andrey mirtchovski
2003-11-02 21:29 ` David Presotto
2003-10-19 14:22 David Presotto
2003-10-16 13:13 David Presotto
2003-10-14 12:11 David Presotto
2003-10-14 14:40 ` a
2003-10-14 15:43   ` Dan Cross
2003-10-12  0:43 matt
2003-10-11 23:43 ` David Presotto
2003-10-12  0:52   ` matt
2003-10-09 16:46 David Presotto
2003-10-09 16:52 ` Richard Miller
2003-09-25 14:24 steve.simon
2003-09-24  0:11 matt
2003-09-24  0:15 ` matt
2003-09-24  0:11 matt
2003-09-16  1:16 David Presotto
2003-09-16  7:38 ` Charles Forsyth
2003-09-01 23:47 matt
2003-09-01 19:14 ` David Presotto
2003-09-01 19:24   ` Skip Tavakkolian
2003-09-02  0:42   ` boyd, rounin
2003-09-01 14:08 David Presotto
2003-08-31 23:46 David Presotto
2003-07-26 16:11 David Presotto
2003-07-23 15:34 Vincenzo Volpe
2003-07-23 16:36 ` jmk
2003-07-26  0:46   ` David Presotto
2003-08-01  9:02     ` Vincenzo Volpe
2003-08-01 17:53       ` David Presotto
2003-06-21 19:15 David Presotto
2003-06-19 13:57 David Presotto
2003-06-19 14:16 ` boyd, rounin
2003-05-10  5:24 Andrew Simmons
2003-04-21 17:54 bigfoot
2003-04-21 18:12 ` David Presotto
2003-04-21 19:06   ` Russ Cox
2003-04-21 19:08     ` rsc
2003-04-25 10:40     ` vic zandy
2003-04-19 13:02 David Presotto
2003-02-25 12:40 Steve Simon
2003-02-24 16:52 Steve Simon
2003-02-24 16:06 ` Wayne Walker
2003-02-24 17:18   ` William Josephson
2003-02-24 19:37 ` northern snowfall
2003-02-24 13:49 David Presotto
2003-02-24 15:11 ` Sam
     [not found] <2ba8f07c025d45604e247b27a02d4123@plan9.bell-labs.com>
2003-02-23  6:14 ` Leendert van Doorn
2003-02-17 15:30 Steve Simon
2003-02-14 16:19 Steve Simon
2003-02-12 15:41 David Presotto
2003-02-12 15:37 David Presotto
2003-02-12 15:34 David Presotto
2003-02-10 17:20 Steve Simon
2003-02-10 18:26 ` Russ Cox
2002-12-03  9:02 Ian Dichkovsky
2002-12-01 20:33 bwc
2002-12-01 17:38 Skip Tavakkolian
2002-12-01 15:46 presotto
2002-11-19 20:04 presotto
2002-11-19 19:36 bwc
2002-11-19 19:50 ` George Michaelson
2002-11-19  1:44 bwc
2002-11-18 21:40 bwc
2002-11-18 21:39 bwc
2002-11-18 21:39 bwc
2002-10-17  3:49 rob pike, esq.
2002-09-30 23:48 Adrian L. Thiele
2002-09-19 17:54 Sape Mullender
     [not found] <20020814092910.8DBA973C99@wintermute.cse.psu.edu>
     [not found] ` <3D5AC220.F7A7ED77@null.net>
2002-08-15  9:55   ` matt
2002-08-15 16:24   ` Ronald G Minnich
2002-08-15 17:08   ` Dennis Davis
2002-07-19  0:59 presotto
2002-07-16 19:21 presotto
2002-07-03 13:17 presotto
2002-06-10 19:10 Russ Cox
2002-04-12 17:43 Russ Cox
2002-04-12 17:20 /dev/null
2002-03-12  1:04 markp
2002-03-12  9:42 ` Thomas Bushnell, BSG
2002-03-13 10:04   ` bs
2002-03-11 18:33 Russ Cox
2002-03-12  9:42 ` Thomas Bushnell, BSG
2002-03-11 16:28 bwc
2002-03-11 16:24 bwc
2002-03-11 15:57 presotto
2002-03-11 17:51 ` Thomas Bushnell, BSG
2002-03-12  9:42   ` ozan s yigit
2002-03-11 19:51 ` Sam Ducksworth
2002-03-11 19:53 ` Andrew Simmons
2002-03-12 11:05 ` Anthony Mandic
2002-03-13 10:05 ` Douglas A. Gwyn
2002-02-28 11:26 sape
2002-03-04  6:51 ` Sean Quinlan
2002-02-27 22:47 presotto
2002-02-27 17:57 stanv
2001-12-13 14:35 presotto
2001-12-13 15:10 ` Ronald G Minnich
2001-12-13 15:47 ` Lucio De Re
2001-12-11 18:27 bwc
2001-12-11 18:17 Russ Cox
2001-12-11 18:17 bwc
2001-12-11 16:24 Russ Cox
2001-12-11 16:33 ` Boyd Roberts
2001-12-09 14:48 rob pike
2001-12-11 10:07 ` Douglas A. Gwyn
2001-12-11 11:55   ` Boyd Roberts
2001-12-12  9:47     ` Douglas A. Gwyn
2002-01-02 10:04       ` John R. Strohm
2002-01-03  9:52         ` Douglas A. Gwyn
2001-12-12  9:48   ` Thomas Bushnell, BSG
2001-12-12 11:14     ` Boyd Roberts
2001-12-09  8:22 arisawa
2001-11-30 14:14 steve.simon
2001-11-30 14:30 ` Boyd Roberts
2001-11-01 21:27 presotto
2001-11-01 21:26 presotto
2001-10-26 18:10 presotto
2001-10-26 14:45 peh
2001-09-07 13:48 Peter Bosch
2001-09-05  7:25 Fco.J.Ballesteros
2001-09-04 13:30 Fco.J.Ballesteros
2001-09-04 20:51 ` Martin Harriss
2001-09-04 12:08 geoff
2001-08-14 11:10 Usenet News system
2001-08-12 21:38 Philippe Anel
2001-08-13  7:45 ` andrey mirtchovski
2001-08-14  9:44   ` Ralph Corderoy
2001-08-05 14:02 jmk
2001-05-20  1:41 rob pike
2001-05-20  6:31 ` Dan Cross
2001-05-20 12:40   ` Donald Brownlee
2001-05-20 13:16     ` Boyd Roberts
2001-05-20 19:38     ` Dan Cross
2001-05-20 19:57       ` Richard Elberger
2001-05-21  4:56         ` Jonathan Sergent
2001-04-09 14:52 presotto
2001-04-09 13:47 forsyth
2001-04-09 13:26 presotto
2001-03-30 15:56 presotto
2001-03-22 15:09 Gorka Guardiola Muzquiz
2001-03-06 14:44 presotto
2000-11-29  8:03 Russ Cox

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