Mike's Linux Scripts

I've always loved programming. Since moving to Linux however, I've found that writing scripts and the like is that much easier and more productive. Please consider some of my offerings below. All are licensed under the GPL version 2 or later.

Scripts I've done:

Let's start here ... these scripts are mine or my modifications to others'. They are under the GPL ... I don't mind if you use and modify them (please send me improved versions), just don't take my name out of them unless you make something extremely big out of it and my effort seems meaningless (in which case you must still notify me) :).

BIND root server updating

Everyone has a version of this one practically. If you know of a vastly superior one, tell me so I can use it instead. Basically it asks for an updated copy of the root servers list from rs.internic.net. You may have to change the file names or directories to reflect your configuration.

• Al Longyear & Micolai Langfeldt's root server update script.

Copy the above to a file and then save it in your /etc/cron.monthly directory (or run it directly from crontab).

Programs like portsentry (see Freshmeat listing) offer the option of blocking an address that has probed you for listening sockets, etc. via firewall blocks or route dropping. It is often desired that these actions not be permanent, especially in the case of a potential DoS attack or if the scanner was on a dynamic IP (which may end up being a legitimate user in a few minutes). For these cases, I created the following script (also available for download):

Note: Code released under LGPL version 2 or later.

#!/bin/sh

if [ "x$1" = "x" ]; then exit 0; fi
if [ "x$2" = "x" ]; then exit 0; fi

TARGET=$1	# IP address or name
TIMEOUT=$2	# In seconds

/sbin/ipchains -A input -s $TARGET -j DENY -l && \
sleep $TIMEOUT && \
/sbin/ipchains -D input -s $TARGET -j DENY -l

If you want to use this with portsentry, simply copy the script to /usr/sbin/tempblock.sh, comment out all KILL_ROUTE lines in your portsentry.conf and add the following in their place (to block the address for 30 minutes):

KILL_ROUTE=/usr/sbin/tempblock.sh $TARGET$ 1800

HylaFAX init.d entry

HylaFAX does a great job of sending both faxes and pages over a network, but the startup and shutdown via init.d left a bit to be desired for my RedHat blood. Here's my version:

Copy this into a file called /etc/rc.d/init.d/hylafax

#! /bin/sh
#
# fax server control

. /etc/rc.d/init.d/functions

FAXQ=/usr/sbin/faxq
HFAXD=/usr/sbin/hfaxd
FAXQUIT=/usr/sbin/faxquit
FAXPORT=hylafax			# designated port for new protocol
SNPPPORT=snpp			# official port for SNPP

FAXSTAT=/usr/bin/faxstat
FAXSTATOPTS="-i -r -s -l"	# additional info, receive and send queues, localtime

case $1 in
'start')
	echo -n "Starting HylaFAX queue handler (faxq)"
	daemon $FAXQ
	echo
	echo -n "Starting HylaFAX daemon (hfaxd)"
	daemon $HFAXD -i $FAXPORT -s $SNPPPORT
	echo
	;;
'stop')
	$FAXQUIT >/dev/null 2>&1
	echo -n "Stopping HylaFAX daemon (hfaxd)"
	killproc hfaxd
	echo
	;;
restart)
	$0 stop
	action "Waiting 5 seconds" sleep 5
	$0 start
	;;
status)
	$FAXSTAT $FAXSTATOPTS
	;;
*)
	echo "usage: /etc/init.d/hylafax {start|stop|restart|status}"
	;;
esac

EtermExec

I run certain programs in transparent Eterm windows and sometimes do so remotely. I like to know where I'm running an app from and so I wrote this quick script:

#!/bin/sh

if [ "$2" = "" ]; then
   TERMNAME="Terminal @ `hostname`"
else
   TERMNAME="$2 @ `hostname`"
fi

if [ "$1" = "" ]; then
   exit 0
fi

Save this as, for example, /usr/bin/etermexec and use it to run programs like pine or tin. It accepts two arguments, the name of the application to run in the window, and the name to put in the titlebar. The name of the machine its executed from will be automatically appended. For example: (the last example is depicted to the right)

• etermexec pine E-mail
• etermexec tin "Read News"
• etermexec top "Top processes"

Note: To produce borderless windows on E, I simply have it "remember" that the window with a given title is borderless and then specify that title.

Colourising your system logs

This is a quick script I did after realising that other such tools didn't do what I wanted. The first time I saw colour-coded HTML or C in a good IDE, I never wanted to go back. I hope you have a similar experience after running something like:
cat /var/log/messages | /usr/local/bin/logcolorize.pl

Note: it seems that Redhat is including logcoloriser in their Power Tools (see here). Also, I now use my etermexec script, above, to produce the scrolling output.

It is currently at version 1.0.8. If you want to follow it, watch for announcements on Freshmeat. If you find it's useful or wonderful after using it, please add a comment to it's Freshmeat listing.

zcat /var/log/apcupsd.log.1.gz | /bin/perl /usr/local/bin/apcloganalyser.pl > /home/httpd/html/apcups.html

syntax region cglibfunc start="g_" end="("me=s-1
syntax region cgdkfunc start="gdk_" end="("me=s-1
syntax region cgtkfunc start="gtk_" end="("me=s-1
hi link cglibfunc glibfunc
hi link cgdkfunc gdkfunc
hi link cgtkfunc gtkfunc

syn match cglibfunc "\<g_[a-z]*\ *("me=s-1
syn match cgdkfunc "\<gdk_[a-z]*\ *("me=s-1
syn match cgtkfunc "\<gtk_[a-z]*\ *("me=s-1

hi glibfunc guifg=cyan
hi gdkfunc guifg=cyan
hi gtkfunc guifg=cyan