Improved grep version:
% glark
+--
+Grep with highlighting:
-glark grep extract-matches
+% grep --color=auto ...
+% hgrep ...
--
-Highlith
+Extract matches when grepping:
-grepc
-hgrep
+Usage examples:
+% ifconfig | grepc 'inet addr:(.*?)\s'
+% ifconfig | glark --extract-matches 'inet addr:(.*?)\s'
--
Output text as sound:
Develop, test and use exploit code with the Metasploit Framework:
cd /tmp
-wget http://www.metasploit.com/tools/framework-2.7-snapshot.tar.gz
-unp framework-2.7-snapshot.tar.gz
-cd framework*
+wget http://framework-mirrors.metasploit.com/msf/downloader/framework-3.0.tar.gz
+unp framework-3.0.tar.gz
+cd framework-3.0
./msfcli
--
Useful documentation:
remote host:
% netcat 192.168.0.1 3333
--
+Reverse Shell via SSH:
+
+local host (inside the network):
+% ssh -NR 1234:localhost:22 remote_host
+
+remote host (outside the network):
+% ssh localhost -p 1234
+--
Remove empty directories with zsh:
% rmdir ./**/*(/od) 2> /dev/null
See also: http://www.debian.org/releases/stable/i386/apcs04.html.en
Avoid all of the above steps - use grml-debootstrap(8) instead!
--
-Convert files from Unicode / UTF to ISO:
+Convert files from Unicode / UTF-8 to ISO:
% iconv -f utf8 -t iso-8859-15 < utffile > isofile
Adjust system for use of qemu with kqemu:
Make sure you have all you need:
-# apt-get update ; apt-get install qemu grml-kerneladdons
+# apt-get update ; apt-get install qemu grml-kerneladdons-$KERNELVERSION
Then set up kqemu:
% startx 2>~/.xsession-errors &| exit
--
-Which process is writing to disk?
+Which process is writing to disk and/or causes the disk to spin up?
+
+First of all use lsof to check what's going on. Does not help? ->
# echo 1 > /proc/sys/vm/block_dump
-Warning: you must disable syslogd before you do this, or you must
-make sure that kernel output is not logged.
+The command sets a sysctl to cause the kernel to log all disk
+writes. Please notice that there is a lot of data. So please
+disable syslogd/syslog-ng before you do this, or you must make
+sure that kernel output is not logged.
When you're done, disable block dump using:
# echo 0 > /proc/sys/vm/block_dump
Alternative:
laptop-mode-tools provides a tool named lm-profiler (laptop mode profiler)
which handles block_dump on its own.
+
+See: $KERNEL-SOURCE/Documentation/laptop-mode.txt
+
+Also take a look at event-viewer(8) which is part of grml-debugtools.
--
Install initrd via initramfs-tools for currently running kernel:
# xfs_admin -l /dev/sda1
reiserfs without vol_id:
-# debugreiserfs /dev/sda1 | grep UUID
+# debugreiserfs /dev/sda1 | grep -i label
+
+jfs without vol_id:
+# jfs_tune -l /dev/sda1 | grep -i label
reiser4 without vol_id:
-# debugfs.reiser4 /dev/sda1 | grep uuid
+# debugfs.reiser4 /dev/sda1 | grep -i label
--
Check filesystem's UUID:
# vol_id -u /dev/sda1
ext2/3 without vol_id:
-# dumpe2fs /dev/sda1 | grep UUID
+# dumpe2fs /dev/sda1 | grep -i UUID
xfs without vol_id:
# xfs_admin -u /dev/sda1
reiserfs without vol_id:
-# debugreiserfs /dev/sda1 | grep LABEL
+# debugreiserfs /dev/sda1 | grep -i UUID
reiser4 without vol_id:
-# debugfs.reiser4 /dev/sda1 | grep label
+# debugfs.reiser4 /dev/sda1 | grep -i UUID
+--
+Change a filesystem's LABEL:
+
+swap:
+# mkswap -L $LABEL /dev/sda1
+
+ext2/ext3:
+# e2label /dev/sda1 $LABEL
+# tune2fs -L $LABEL /dev/sda1
+
+reiserfs:
+# reiserfstune -l $LABEL /dev/sda1
+
+jfs:
+# jfs_tune -L $LABEL /dev/sda1
+
+xfs:
+# xfs_admin -L $LABEL /dev/sda1
+
+fat/vfat:
+# echo 'drive i: file="/dev/sda1"' >> ~/.mtoolsrc
+# mlabel -s i:$LABEL
+
+ntfs:
+# ntfslabel $LABEL /dev/sda1
--
Disable pdiffs feature of APT:
More usage examples: man zsplit + man unzsplit
--
-Measure network performance using ipserf
+Measure network performance using iperf:
Server side:
% iperf -s -V
# /usr/share/mplayer/scripts/win32codecs.sh
+or
+
+# /usr/share/mplayer/scripts/binary_codecs.sh install
+
+(depending on the mplayer version you have).
+
To play encrypted DVDs and if you are living in a country where using
libdvdcss code is not illegal can install Debian package libdvdread3
and use the script /usr/share/doc/libdvdread3/install-css.sh.
Start dnsmasq finally:
# Restart dnsmasq
--
-Find out which process(es) cause the disk to spin up:
+Display stats about memory allocations performed by a program:
-# echo 1 > /proc/sys/vm/block_dump
+Usage example for 'ls':
-The command sets a sysctl to cause the kernel to log all disk
-writes. Please notice that there is a lot of data.
+% LD_PRELOAD=/lib/libmemusage.so ls > /dev/null
+--
+Use KVM (Kernel-based Virtual Machine for Linux):
-See: $KERNEL-SOURCE/Documentation/laptop-mode.txt
+Make sure to install the relevant tools:
+# apt-get update ; apt-get install kvm
+# modprobe kvm
-Also take a look at event-viewer(8).
+Test it with a minimal system like ttylinux:
+# wget http://www.minimalinux.org/ttylinux/packages/bootcd-i386-5.3.iso.gz
+# gzip -d bootcd-i386-5.3.iso.gz
+# kvm -cdrom bootcd-i386-5.3.iso
--
-Display stats about memory allocations performed by a program:
+EEPROM data decoding for SDRAM DIMM modules:
-Usage example for 'ls':
+# modprobe eeprom
+# /usr/share/doc/lm-sensors/examples/eeprom/decode-dimms.pl
+--
+Set up and use DVB:
-% LD_PRELOAD=/lib/libmemusage.so ls > /dev/null
+Make sure your device is supported by Linux and running.
+See http://www.linuxtv.org/ for more details.
+
+If the DVB device works on your system (see 'hwinfo --usb'
+when using a DVB usb device for example), then make sure you
+have the scan util from dvb-utils available:
+
+# aptitude install dvb-utils
+
+Then create a channels.conf configuration file:
+
+% scan /usr/share/doc/dvb-utils/examples/scan/... > ~/.mplayer/channels.conf
+
+You can find some example configuration files on
+your grml system in ~/.channels. Usage example:
+
+% ln -s ~/.mplayer/channels.conf-AT-graz ~/.mplayer/channels.conf
+
+Tip: w_scan (see http://free.pages.at/wirbel4vdr/w_scan/index2.html)
+might be useful if you do not know the initial configuration
+details.
+--
+Get the lastest mercurial snapshot:
+
+Make sure you have the python-dev package available:
+# apt-get update ; apt-get install python-dev
+
+Get and build the source:
+% hg clone http://selenic.com/repo/hg mercurial
+% cd mercurial
+% make local
+% export PYTHONPATH=$(pwd)
+% export PATH=$PATH:$(pwd)
+
+now you should have the newest version of mercurial whenever you execute hg.
+
+To update to the lastest development snapshot, additionally use
+the following commands:
+% hg pull -u http://hg.intevation.org/mercurial/crew
+% make local
--
+Configure timezone
+==================
+
+Available bootoptions relevant in live-cd mode:
+-----------------------------------------------
+
+* utc: set UTC, if your system clock is set to UTC (GMT)
+* gmt: set UTC, if your system clock is set to UTC (GMT) [like bootoption utc]
+* tz=$option: set timezone to corresponding $option, usage example:
+ tz=Europe/Vienna
+
+Configuration options relevant on harddisk installation:
+--------------------------------------------------------
+
+* Use the tzconfig utility to set the local timezone:
+
+ # tzconfig
+
+ which adjusts /etc/timezone and /etc/localtime according
+ to the provided information. Running:
+
+ # dpkg-reconfigure tzdata
+
+ might be useful as well.
+
+* /etc/default/rcS: set variable UTC according to your needs,
+ whether your system clock is set to UTC (UTC='yes') or
+ not (UTC='no')
+
+* /etc/localtime: adjust zoneinfo according to your needs:
+
+ # ln -sf /usr/share/zoneinfo/$WHATEVER_YOU_WANT /etc/localtime
+
+ The zoneinfo directory contains the time zone files that were
+ compiled by zic. The files contain information such as rules
+ about DST. They allow the kernel to convert UTC UNIX time into
+ appropriate local dates and times. Use the zdump utility to
+ print current time and date (in the specified time zone).
+
+* /etc/adjtime: This file is used e.g. by the adjtimex function,
+ which can smoothly adjust system time while the system runs
+
+* If you change the time (using 'date --set ...', ntpdate,...)
+ it is worth setting also the hardware clock to the correct time:
+
+ # hwclock --systohc [--utc]
+
+ Remember to add the --utc -option if the hardware clock is set
+ to UTC!
+
+Still problems?
+---------------
+
+Check your current settings via:
+
+ cat /etc/timezone
+ zdump /etc/localtime
+ echo $TZ
+ hwclock --show
+ grep hwclock /etc/runlevel.conf
+ grep '^UTC' /etc/default/rc
+
+Further information:
+--------------------
+
+ hwclock(8) tzselect(1) tzconfig(8)
+ http://www.debian.org/doc/manuals/system-administrator/ch-sysadmin-time.html
+ http://wiki.debian.org/TimeZoneChanges
+--
+Recorder shellscript session using script:
+
+% script -t 2>~/upgrade.time -a ~/upgrade.script
+% scriptreplay ~/upgrade.time ~/upgrade.script
+--
+Test UTF-8 capabilities of terminal:
+
+wget http://melkor.dnp.fmph.uniba.sk/~garabik/debian-utf8/download/UTF-8-demo.txt.gz
+zcat UTF-8-demo.txt.gz
+
+or:
+
+wget http://www.cl.cam.ac.uk/~mgk25/ucs/examples/UTF-8-test.txt
+cat UTF-8-test.txt
+--
+UTF-8 at grml / some general information regarding Unicde/UTF-8:
+
+ http://wiki.grml.org/doku.php?id=utf8
+--
+
+This allows one ssh connection attepmt per minute per source ip, with a initial
+burst of 10. The available burst is like a counter which is initialised with
+10. Every connection attempt decrements the counter, and every minute where the
+connection limit of one per minute is not overstepped the counter is
+incremented by one. If the burst counter is exhausted the real rate limit
+comes into play. This gives you 11 connectionattepmts in the first minute
+before blocked for 10minutes. After 10 minutes block the game restarts.
+
+Hint: you could set the burst value to 5 and the block time to only 5 minutes
+to achive the same average connection rate but with halve the block time.
+
+iptables -A inet_in -p tcp --syn --dport 22 -m hashlimit --hashlimit-name ssh \
+ --hashlimit 1/minute \ --hashlimit-burst 10 --hashlimit-mode srcip \
+ --hashlimit-htable-expire 600000 -j ACCEPT
+iptables -A inet_in -p tcp --dport 22 -m state --state NEW -j REJECT
+--
+Tunnel a specific connection via socat:
+
+On the client:
+% socat TCP4-LISTEN:8003 TCP4:gateway:500
+
+On the gateway:
+# socat TCP4-LISTEN:500,fork TCP4:target:$PORT
+
+Using localhost:8003 on the client uses the tunnel now.
+--
+Set date:
+
+# date --set=060916102007
+
+where the bits are month(2)/day(2)/hour(2)/minute(2)/year(4)
+
+Set date using a relative date:
+
+# date -s '+3 mins'
+
+or
+
+# date -s '+tomorrow'
+
+Display a specific relative date:
+
+# date -d '+5 days -2 hours'
+
+Don't forget to set hardware clock via:
+
+# hwlock -w
+--
+Booting grml via network / PXE:
+
+Start grml-terminalserver on a system with network access
+and where grml is running:
+
+# grml-terminalserver
+
+Then booting your client(s) via PXE should work without
+any further work.
+--
+Debugging SSL communications:
+
+% openssl s_client -connect webmail.grml.org:993
+
+# ssldump -a -A -H -i eth0
projects / grml-tips.git / blobdiff