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Posts

[ 20081011081638 ]
creating busybox symlinks

[ 20081002215121 ]
wmiirc-lua v0.2.5 release

[ 20080916155113 ]
git-svn strangeness

[ 20080915112959 ]
installilng git man pages quickly

[ 20080913112345 ]
wmiirc-lua v0.2.4 release

[ 20080825100454 ]
Kernel Walkthroughs - booting

[ 20080813210205 ]
Linux Kernel Booting

[ 20080719211329 ]
printable OLS/2008 schedule

[ 20080715214447 ]
wmiirc-lua updates

[ 20080713194704 ]
Git Screencast

[ 20080713143429 ]
four steps to reproducible Debian installs

[ 20080705150651 ]
USB2.0 enclosure benchmark

[ 20080703230924 ]
Linux Kernel Walkthroughs posted

[ 20080702113602 ]
Introducing the Ottawa Ruby folks to Git

[ 20080628160732 ]
Authenticating Linux against OSX LDAP directory

[ 20080627142123 ]
Canada Day Events 2008

[ 20080613162541 ]
Linux Kernel Walkthroughs

[ 20080510083828 ]
is my usb device connected to a fast port?

[ 20080509111534 ]
show more git info on zsh prompt

[ 20080430104202 ]
git-vim

[ 20080412100337 ]
color your word

[ 20080404105620 ]
show current git branch on zsh prompt (2)

[ 20080303200359 ]
how to track multiple svn branches in git

[ 20080301134220 ]
fixing X for GeodeLX

[ 20080108002540 ]
kvm nfs hang

[ 20080107160836 ]
screen -c relative path bug

[ 20080105132854 ]
WeeChat spell suggestions

[ 20071219221358 ]
show current git branch in zsh

[ 20071217141037 ]
wmiirc-lua kitchen sink repository

[ 20071212100316 ]
protecting sshd from OOM killer

[ 20071204234232 ]
wmiirc-lua v0.2.1 remembers a bit more

[ 20071013205336 ]
wmiirc-lua v0.2 has suspend and raw modes

[ 20070929112345 ]
wmiirc-lua debianization

[ 20070924104140 ]
zsh tip of the day - global aliases

[ 20070915094213 ]
wmiirc-lua v0.1.1

[ 20070913130838 ]
comparing two directories

[ 20070909204125 ]
git-rebase --interactive

[ 20070908115905 ]
zsh tab completion awesomeness

[ 20070902000736 ]
wmiirc in lua

[ 20070831150306 ]
debugging with -dbg libraries

[ 20070831142646 ]
svn status like output in git

[ 20070829141847 ]
Git Cheat Sheet

[ 20070821142038 ]
switching to abiword

[ 20070811105746 ]
forwarding ssh and X through screen

[ 20070807112531 ]
git-svnup

[ 20070724082355 ]
reducing power consumption

[ 20070722123734 ]
Makefile template

[ 20070722002649 ]
less, colourful

[ 20070719162359 ]
irssi docs

[ 20070716114553 ]
qemu eats up /dev/shm

[ 20070710214512 ]
git-clean in svn land

[ 20070705113139 ]
ipw2200 not working

[ 20070627191916 ]
git slides updated

[ 20070618220649 ]
unpopular debian packages on my system

[ 20070611125852 ]
git-svn with multiple branches

[ 20070517085321 ]
Linus on Git at Google

[ 20070510134551 ]
vim modelines insecure

[ 20070504205042 ]
bios disassembler

[ 20070504124124 ]
dd hex arguments

[ 20070503013555 ]
urxvt mouseless url yanking

[ 20070502211941 ]
gitdiff.vba v2

[ 20070419234350 ]
india

[ 20070418155857 ]
zsh fun

[ 20070418143632 ]
pipe to pastey.net

[ 20070418094151 ]
vimgrep alias

[ 20070416202545 ]
mouse-free

[ 20070406141850 ]
ATA messages via SCSI layer

[ 20070330221019 ]
GITDiff vim plugin

[ 20070329011735 ]
git presentation for OCLUG

[ 20070328123631 ]
fixing vim's [[ and ]] for bad code

[ 20070316092236 ]
pxeboot and nfsroot with debian

[ 20070312134706 ]
etc snapshots with git

[ 20070307004041 ]
remote power switch

[ 20070222215355 ]
klips-less openswan git tree

[ 20070221041316 ]
git caching for v1.5.x

[ 20070218002214 ]
klips loses zlib

[ 20070209172606 ]
vim and linux CodingStyle

[ 20070207205427 ]
my kqemu install

[ 20070204100100 ]
leaner meaner openswan

[ 20070115111917 ]
wmii+ruby xlock action

[ 20070112131252 ]
cloning xterms in wmii+ruby

[ 20070102010551 ]
wmii+ruby talk for OCLUG

[ 20061228220641 ]
dump and restore

[ 20061218100219 ]
C style

[ 20061101002027 ]
fetching all git branches from remote

[ 20061028111607 ]
local caching for git repos

[ 20061020145437 ]
automatic version creation with git

[ 20061018213306 ]
wmii w/ ruby wmiirc

[ 20061018201907 ]
small fonts

[ 20061007151802 ]
google-codesearch from vim

[ 20060928020813 ]
shell commands

[ 20060920093957 ]
letting screen apps use the ssh-agent

[ 20060908223613 ]
mpdscribble stream support

[ 20060907125149 ]
glGo on ubuntu/dapper amd64

[ 20060906163240 ]
lbdb and mutt

[ 20060902145643 ]
vim tutorial

[ 20060902135722 ]
fixing your terminal

[ 20060828124713 ]
apt-get pdiffs

[ 20060824224842 ]
256 colour xterms

[ 20060824152658 ]
dynamic IPcomp

[ 20060824145428 ]
inkscape++

[ 20060818150516 ]
tags/cscope for system headers

[ 20060805131557 ]
opteron 170, part 4

[ 20060805101941 ]
opteron 170, part 3

[ 20060803233234 ]
opteron 170, part 2

[ 20060802210126 ]
opteron 170

[ 20060729144129 ]
OLS keysigning / 2006

[ 20060728105500 ]
git-find findings

[ 20060727162941 ]
starting on git-find

[ 20060727113632 ]
git-graft and git-find brainstorm

[ 20060726224531 ]
pretty function tracing

[ 20060713174723 ]
uml and multiple network segments

[ 20060707182236 ]
lastfm artist and title to clipboard

[ 20060706162256 ]
reverting a git changeset

[ 20060629212003 ]
user #3

[ 20060628083456 ]
firefox crashes with form input

[ 20060621151402 ]
git vs hg

[ 20060612222204 ]
ldap account management

[ 20060612194523 ]
stupid ldap

[ 20060608092157 ]
rpm hell is right

[ 20060605095726 ]
OpenSSH VPNs

[ 20060604114317 ]
Lenovo lost a customer

[ 20060601234010 ]
generating html colourized sourcecode

[ 20060601211716 ]
ion3 greatness and acting on X selections

[ 20060526085644 ]
software RAID10 performance

[ 20060525234148 ]
learning to love git

[ 20060524121638 ]
recent vim7 articles

[ 20060516095748 ]
bootstrapping debian on my sbc

[ 20060428145140 ]
entropy injection

[ 20060423140628 ]
Adam

[ 20060414202507 ]
converting mp3s to CD

[ 20060413232836 ]
secure apt-get

[ 20060412194423 ]
xen domain0 on debian

[ 20060410220525 ]
LVM2 on RAID1 mirror

[ 20060410102824 ]
building a RHEL4 kernel w/ kdb support

[ 20060407230939 ]
xen on debian

[ 20060407230818 ]
Upgraded look

[ 20060330131334 ]
Flattered by a copy

[ 20060328165153 ]
vim7 from source

[ 20060308123539 ]
Perl, Catalyst, CPAN, and Debian

[ 20060308123302 ]
last.fm

[ 20060128124841 ]
carcassonne and zombies

[ 20060120135931 ]
Election Humour

[ 20050925130002 ]
ldap on debian

[ 20050528190034 ]
Error while mapping shared library sections

[ 20050124130158 ]
IRC over email gateway

[ 20050110225522 ]
brute force attacks sshd?

[ 20050108095026 ]
LDAP authentication (part 1)

[ 20041124130146 ]
sawfish workspace themes

[ 20041113082651 ]
Mini-DV to divx using mencoder

[ 20040326082602 ]
bash vi editing mode

[ 20040305163216 ]
cool debian tools

...

vim modelines insecure

[ link: vim-modelines-insecure | tags: vim security | updated: Thu, 10 May 2007 13:54:00 ]

I have previously disabled modelines in my vimrc, but had turned them on recently only to learn today that they are subject to another vulnerability.

I've seen this before. Enough is enough. :)

Fortunately, this sparked a debate on vim-dev mailing list. One of the outcomes is a vim script that replaces the modeline parser in vim. It is said to be a lot more strict about what it permits as valid modeline components and allows the user to control that in the vimrc.

You can grab the script, put it in your .vim/plugins/ directory and turn off the built-in modelines parser:

    set modelines=0

Optionally you can set this variable to have the new parser show errors in parsing.

    let g:secure_modelines_verbose=1

OpenSSH VPNs

[ link: openssh-vpn | tags: ssh vpn security | updated: Tue, 06 Jun 2006 20:37:57 ]

Long time ago, I wrote a brief howto on SSH + PPP = VPN (don't use it). Today I found out that as of version 3.4 OpenSSH supports VPN features. That is, you can create a tun device and route packets through your ssh connection.

That's pretty neat if you only have ssh to go with. But pretty crappy because you need root on both ends, and if you have root on both ends you can gowith IPSEC or OpenVPN/tinc/cipe/etc.

secure apt-get

[ link: 20060413232836 | tags: debian apt security | updated: Fri, 05 May 2006 19:09:08 ]

Debiean-heads might find it interesting that Joey Hess has produced a detailed SecureApt article on how to use security features of apt-get.

The particularly interesting bits are:

details about the security levels put into packages
examples of how apt-key aught to be used
timeline that the debian pgp keys will adhere to
problems to be avoided and symptoms you will see if you have 'em
links to relevant documentation

brute force attacks sshd?

[ link: 20050110225522 | tags: security linux | updated: Mon, 10 Jan 2005 22:55:22 ]

This will show you the IP addresses that have failed to login as well 
as the number of attempts that failed.  

grep 'Failed password ' /var/log/auth.log | sed 's/^.* \([0-9]\+\.[0-9]\+\.[0-9]\+\.[0-9]\+\) .*$/\1/' | sort  | uniq -c | sort -n | tail -n 10

You can safely ignore a few failed attempts, but I was getting close to 
3000 over the last week from one IP.  I decided that warranted some 
action. :)

I will probably grow this to a script that will automatically generate
and maintain a "evil IP list" in iptables.  For now you can take the top
offenders and drop them into a -j DROP rule.

Bart Trojanowski
http://www.jukie.net/~bart
bart@jukie.net