Split exercise 5 into its own repository

Labb8/ovning5.md

@@ -0,0 +1,5 @@
+# Exercise 5 #
+
+This exercise now lives in it's own repository at
+[jackbenny/failedlogins](https://github.com/jackbenny/failedlogins)
+

Labb8/ovning5/README.md

@@ -1,27 +0,0 @@
-# failed\_logins.sh #
-This is a small Bash script I wrote for a programming & scripting course at
-school. The script checks for failed SSH logins in /var/log/auth.log by default.
-The failed logins are then sent by e-mail to the admin user specified in the
-Admin variable.
-The script only mails new failed login attempts since it was last run to avoid 
-cluttering the admin's mailbox.
-
-## Usage ##
-The script is meant to run from a cronjob, for example once every hour or day
-or whatever suits your needs. An example (15 minutes after every hour) would be:
-```
-15 * * * * /home/admin/failed_logins.sh
-```
-
-## Compability ##
-So far I've only tested it on Ubuntu 13.04. The binaries used in the script are
-hardcoded to avoid unsane environments. The path to these hardcoded binaries
-could change on other Linux dists and other *NIX.
-
-The script uses sed, awk (standrad awk), egrep, cat, printf, mail, rm, tail,
-mktemp and regular grep. All of these utilities are pretty standard on a 
-Debian/Ubuntu machine, except for mail which is not included in for example 
-Ubuntu Desktop. On both Ubuntu and Debian this can be installed with 
-`sudo apt-get install mailutils`.
-
-

Labb8/ovning5/configure.sh

@@ -1,52 +0,0 @@
-#!/bin/bash
-
-# Jack-Benny Persson
-# LX13
-# Configuration script to update the hardcoded binaries
-
-# Variables
-Binaries=(sed awk egrep mail printf cat grep mktemp rm tail)
-File="failed_logins.sh"
-TempFile=`mktemp -t failed_logins.XXXXXX`
-StartBin=8
-EndBin=17
-
-# Check that they are all installed
-for bin in ${Binaries[@]}; do
-	whereis $bin | awk '{ print $2 }' | grep $bin &> /dev/null
-	if [ $? -ne 0 ]; then
-		echo "It seems you system dosen't have $bin installed"
-		exit 1
-	fi
-done
-
-# Make a temporary copy of the original file
-cp $File $TempFile
-
-# Loop through all the binaries to extract the path and make new
-# variables for the script looking like this: Binary="/bin/binary"
-Index=0
-for i in ${Binaries[@]}; do
-	NewBins[$Index]=$(echo "$i=\"`whereis $i | awk '{ print $2 }'`\"" | \
-		sed "s/\b\(^.\)/\u\1/g")
-	((Index++))
-done
-
-# Replace the old variables for the new ones
-cat $TempFile | sed "{
-/Sed=/c${NewBins[0]}
-/Awk=/c${NewBins[1]}
-/Egrep=/c${NewBins[2]}
-/Mail=/c${NewBins[3]}
-/Printf=/c${NewBins[4]}
-/Cat=/c${NewBins[5]}
-/Grep=/c${NewBins[6]}
-/Mktemp=/c${NewBins[7]}
-/Rm=/c${NewBins[8]}
-/Tail=/c${NewBins[9]}
-}" > $File
-
-# Clean up
-rm $TempFile
-
-exit 0

Labb8/ovning5/failed_logins.sh

@@ -1,125 +0,0 @@
-#!/bin/bash
-
-# Jack-Benny Persson
-# LX13
-# Exercise 5 on lab 8 (Write a script to check for failed logins)
-
-# Binaries
-Sed="/bin/sed"
-Awk="/usr/bin/awk"
-Egrep="/bin/egrep"
-Mail="/usr/bin/mail"
-Printf="/usr/bin/printf"
-Cat="/bin/cat"
-Grep="/bin/grep"
-Mktemp="/bin/mktemp"
-Rm="/bin/rm"
-Tail="/usr/bin/tail"
-
-# Variables
-Admin="jake"
-Authlog="/var/log/auth.log"
-StampTemp="/tmp/failed_login_last_stamp.tmp"
-LineTemp="/tmp/failed_login_last_line.tmp"
-StartLine=1 # Don't change this!
-New=0 #Don't change this!
-
-# Functions
-check_for_new_failed()
-{
-	$Sed -n "$StartLine,\$p" $Authlog | $Egrep "Failed password" \
-		&> /dev/null
-	if [ $? -eq 0 ]; then
-		New=1
-	fi	
-}
-
-show_failed_logins()
-{
-	$Sed -n "$StartLine,\$p" $Authlog | $Egrep "Failed password" | \
-	$Sed 's/invalid user//' | \
-	$Awk '{ print $1" "$2" "$3" \t"$9"\t\t"$11 }'
-}
-
-save_last_stamp_and_line()
-{
-	show_failed_logins | $Awk '{ print $1" "$2" "$3 }' \
-		| $Sed -n '$p' > $StampTemp
-	LastStamp=`$Cat $StampTemp`
-
-	$Cat $Authlog | $Sed -n "/$LastStamp/{
-	=
-	p
-	}" | $Tail -n2 | $Sed -n '/^[0-9]/p' > $LineTemp
-}
-
-# Sanity checks
-if [ ! -r $Authlog ]; then
-	echo "Can't read $Authlog"
-	exit 1
-fi
-
-for Bin in $Sed $Awk $Egrep $Mail $Printfi $Cat $Grep $Mktemp $Rm $Tail; do
-	if [ ! -x $Bin ]; then
-		echo "Can't execute $Bin"
-		exit 1
-	fi
-done
-
-if [ -e $StampTemp ] || [ -e $LineTemp ]; then
-	if [ ! -w $StampTemp ] || [ ! -w $LineTemp ] ; then
-		$Printf "Can't write to temp files, perhaps this script "
-		$Printf "has been run be a different user before?\n"
-		$Printf "Consider changing the temp filenames variable\n"
-		exit 1
-	fi
-fi
-
-if [ ! -w /tmp ]; then
-	echo "Can't write to /tmp"
-	exit 1
-fi
-
-### Main ###
-
-# First of all, check if we have read the log file before and whatever if has
-# been rotated
-if [ -e $StampTemp ] && [ -e $LineTemp ]; then
-	$Sed -n "`$Cat $LineTemp`p" $Authlog | $Grep "`$Cat $StampTemp`" \
-		> /dev/null
-	if [ $? -eq 0 ]; then                # If the logfile hasn't been 
-		StartLine=`$Cat $LineTemp`   # been rotated, set StartLine
-		((StartLine++))              # from the last run and +1
-	fi
-fi
-
-# Check for new failed login attempts since last run (based on StartLine)
-check_for_new_failed
-
-# Redirect all output below to a temporary file for mailing
-MailTemp=`$Mktemp -t failed_logins_mail.XXXXXX`
-exec 1> $MailTemp
-
-if [ $New -eq 1 ]; then # = if there are new failed logins
-	# Print a nice header
-	$Printf "Date & time\t\tUser\t\tFrom host\n"
-	$Printf "-----------\t\t----\t\t---------\n"
-
-	# Print out the latest failed login attempts
-	show_failed_logins
-
-	# Save the last line and the last timestamp for the next run
-	save_last_stamp_and_line
-fi
-
-# Mail the failed logins if there are any (ie if the MailTemp file is NOT empty)
-if [ -s $MailTemp ]; then
-	$Mail $Admin -s "Failed logins" < $MailTemp
-fi
-
-# Clean up
-if [ -e $MailTemp ]; then
-	$Rm $MailTemp
-fi
-
-exit 0