| 1 |
rabit |
1.1 |
#!/bin/sh |
| 2 |
|
|
#--------------------------------------------------------------------- |
| 3 |
|
|
#- Adjusting net filter updater daemon |
| 4 |
|
|
#- rabit@netfrag.org, 01.11.2004 |
| 5 |
rabit |
1.2 |
I='$Id: anfud.sh,v 1.1 2004/11/12 08:05:09 rabit Exp $' |
| 6 |
rabit |
1.1 |
#--------------------------------------------------------------------- |
| 7 |
|
|
#- Functions: |
| 8 |
|
|
|
| 9 |
|
|
# Syntax: dropaddress <IP_address> |
| 10 |
|
|
# |
| 11 |
|
|
dropaddress() { |
| 12 |
|
|
local IP LogMsg RegEx RuleCount |
| 13 |
|
|
|
| 14 |
|
|
if [ -n "$EXCLUDE" ]; then |
| 15 |
|
|
for IP in $EXCLUDE; do |
| 16 |
|
|
case $1 in |
| 17 |
|
|
($IP) |
| 18 |
|
|
logmessage "Ignoring excluded address '$1'." |
| 19 |
|
|
return 1 |
| 20 |
|
|
;; |
| 21 |
|
|
esac |
| 22 |
|
|
done |
| 23 |
|
|
fi |
| 24 |
|
|
|
| 25 |
|
|
RegEx='DROP.*'$1 |
| 26 |
|
|
RuleCount=`iptables -L INPUT -n | egrep $RegEx | wc -l` |
| 27 |
|
|
|
| 28 |
|
|
if [ $RuleCount == 0 ]; then |
| 29 |
|
|
|
| 30 |
|
|
if [ "$PRETEND" == 1 ]; then |
| 31 |
|
|
logmessage "(PRETEND) Dropping rule for address '$1' now would be inserted." |
| 32 |
|
|
else |
| 33 |
|
|
iptables -I INPUT -s $1 -j DROP |
| 34 |
|
|
|
| 35 |
|
|
LogMsg="Dropping rule for address '$1' has been inserted." |
| 36 |
|
|
logmessage "$LogMsg" |
| 37 |
|
|
|
| 38 |
|
|
[ -n "$LOG_DROPPED" ] && syslogwarning "$LogMsg" |
| 39 |
|
|
fi |
| 40 |
|
|
|
| 41 |
|
|
else |
| 42 |
|
|
logmessage "Address '$1' already gets dropped by $RuleCount rule(s). Doing nothing." |
| 43 |
|
|
fi |
| 44 |
|
|
|
| 45 |
|
|
return |
| 46 |
|
|
} |
| 47 |
|
|
|
| 48 |
|
|
# Syntax: echo_log [<Message>] |
| 49 |
|
|
# |
| 50 |
|
|
echo_log() { |
| 51 |
|
|
[ -n "$LOGTARGET" ] && echo $1 >>$LOGTARGET |
| 52 |
|
|
|
| 53 |
|
|
return $? |
| 54 |
|
|
} |
| 55 |
|
|
|
| 56 |
|
|
# Syntax: end [<ExitVal>] |
| 57 |
|
|
# |
| 58 |
|
|
end() { |
| 59 |
|
|
ExitVal=${1:-0} |
| 60 |
|
|
|
| 61 |
|
|
logmessage "Closing session. Exit code is '$ExitVal'." |
| 62 |
|
|
|
| 63 |
|
|
exit $ExitVal |
| 64 |
|
|
|
| 65 |
|
|
return |
| 66 |
|
|
} |
| 67 |
|
|
|
| 68 |
|
|
# Syntax: includeconf |
| 69 |
|
|
# |
| 70 |
|
|
includeconf() { |
| 71 |
|
|
# If existant, include the 'anfud.conf' file: |
| 72 |
|
|
[ -e /etc/anfud.conf ] && source /etc/anfud.conf |
| 73 |
|
|
|
| 74 |
|
|
return $? |
| 75 |
|
|
} |
| 76 |
|
|
|
| 77 |
|
|
# Syntax: init |
| 78 |
|
|
# |
| 79 |
|
|
init() { |
| 80 |
|
|
# Include the configuration file: |
| 81 |
|
|
includeconf |
| 82 |
|
|
|
| 83 |
|
|
# Set the default output log target: |
| 84 |
|
|
[ -z "$LOGTARGET" ] && LOGTARGET=/var/log/anfud.log |
| 85 |
|
|
|
| 86 |
|
|
echo_log # Before starting, output a blank line. |
| 87 |
|
|
logmessage "Session started ($A)." |
| 88 |
|
|
|
| 89 |
|
|
return |
| 90 |
|
|
} |
| 91 |
|
|
|
| 92 |
|
|
# Syntax: logmessage "<Message>" |
| 93 |
|
|
# |
| 94 |
|
|
logmessage() { |
| 95 |
|
|
echo_log "`date +'%b %e %H:%M:%S'` $N[$$]: $1" |
| 96 |
|
|
|
| 97 |
|
|
return $? |
| 98 |
|
|
} |
| 99 |
|
|
|
| 100 |
|
|
# Syntax: syslogwarning "<Message>" |
| 101 |
|
|
# |
| 102 |
|
|
syslogwarning() { |
| 103 |
|
|
logger -p warning -t $N[$$] $1 |
| 104 |
|
|
|
| 105 |
|
|
return $? |
| 106 |
|
|
} |
| 107 |
|
|
|
| 108 |
|
|
#--------------------------------------------------------------------- |
| 109 |
|
|
#- Signal trapping: |
| 110 |
|
|
|
| 111 |
|
|
trap 'logmessage "Recieved signal 1 (SIGHUP)."; end' 1 |
| 112 |
|
|
trap 'logmessage "Recieved signal 2 (SIGINT)."; end' 2 |
| 113 |
|
|
trap 'logmessage "Recieved signal 3 (SIGQUIT)."; end' 3 |
| 114 |
|
|
#trap 'logmessage "Recieved signal 4 (SIGILL)."; end' 4 |
| 115 |
|
|
#trap 'logmessage "Recieved signal 6 (SIGABRT)."; end' 6 |
| 116 |
|
|
trap 'logmessage "Recieved signal 9 (SIGKILL)."; end' 9 |
| 117 |
|
|
trap 'logmessage "Recieved signal 15 (SIGTERM)."; end' 15 |
| 118 |
|
|
|
| 119 |
|
|
#--------------------------------------------------------------------- |
| 120 |
|
|
#- Constants: |
| 121 |
|
|
|
| 122 |
|
|
# Extract the basename: |
| 123 |
|
|
N=$(basename $0) |
| 124 |
|
|
|
| 125 |
|
|
# Format the CVS ID line: |
| 126 |
|
|
|
| 127 |
|
|
I=${I:5} |
| 128 |
|
|
|
| 129 |
|
|
if [ -n "$I" ]; then |
| 130 |
|
|
#while read Name Ver Date Time User Exp; do |
| 131 |
|
|
# A="${Name/,v} v$Ver by $User ($Date, $Time)" |
| 132 |
|
|
#done < <(echo $I) |
| 133 |
|
|
A=$I |
| 134 |
|
|
else |
| 135 |
|
|
A="No CVS ID yet" |
| 136 |
|
|
fi |
| 137 |
|
|
|
| 138 |
|
|
#- Match masks: |
| 139 |
|
|
|
| 140 |
|
|
# Example lines from '/var/log/auth.log' where SSH login failed: |
| 141 |
|
|
#"Jan 1 00:00:00 machine sshd[1000]: Illegal user admin from 127.0.0.1" |
| 142 |
|
|
#"Jan 1 00:00:00 machine sshd[1000]: Failed password for root from 127.0.0.1 port 30000 ssh2" |
| 143 |
|
|
#"Jan 1 00:00:00 machine sshd[1000]: error: PAM: Authentication failure for root from 127.0.0.1" |
| 144 |
|
|
|
| 145 |
|
|
# Match mask for illegal SSH user login attempt: |
| 146 |
|
|
MatchP1='* sshd*: Illegal user *' |
| 147 |
|
|
|
| 148 |
|
|
# Match masks for SSH logins w/ failed password: |
| 149 |
|
|
MatchN2='* sshd*: Failed * for illegal user * from *' |
| 150 |
|
|
MatchP2='* sshd*: Failed password for * from *' |
| 151 |
|
|
|
| 152 |
|
|
# Match mask for SSH logins w/ incorrect password: |
| 153 |
|
|
MatchN3='* sshd*: error: PAM: Authentication failure for illegal user * from *' |
| 154 |
|
|
MatchP3='* sshd*: error: PAM: Authentication failure for * from *' |
| 155 |
|
|
|
| 156 |
|
|
# Example lines from '/var/log/auth.log' where FTP login failed: |
| 157 |
|
|
#"Jan 1 00:00:00 machine ftpd[17986]: FTP LOGIN FAILED FROM host.domain, root" |
| 158 |
|
|
|
| 159 |
|
|
MatchFTP_P1='* ftpd*: FTP LOGIN FAILED FROM *, *' |
| 160 |
|
|
|
| 161 |
|
|
#--------------------------------------------------------------------- |
| 162 |
|
|
#- Initialise: |
| 163 |
|
|
|
| 164 |
|
|
init |
| 165 |
|
|
|
| 166 |
|
|
#--------------------------------------------------------------------- |
| 167 |
|
|
#- Default parameters: |
| 168 |
|
|
|
| 169 |
|
|
# The log file to be scanned for intrusion attempts: |
| 170 |
|
|
# (default: "SCANLOG=/var/log/syslog") |
| 171 |
|
|
[ -z "$SCANLOG" ] && [ -e /var/log/syslog ] && SCANLOG=/var/log/syslog |
| 172 |
|
|
|
| 173 |
|
|
# On start seek and parse log file from beginning: |
| 174 |
|
|
# (default: "SEEKSTART=1") |
| 175 |
|
|
[ -z "$SEEKSTART" ] && SEEKSTART=1 |
| 176 |
|
|
|
| 177 |
|
|
# Follow the scan log file: |
| 178 |
|
|
# (default: "LOGFOLLOW=1") |
| 179 |
|
|
[ -z "$LOGFOLLOW" ] && LOGFOLLOW=1 |
| 180 |
|
|
|
| 181 |
|
|
# Time between log file scans (in seconds): |
| 182 |
|
|
# (default: "INTERVAL=1") |
| 183 |
|
|
[ -z "$INTERVAL" ] && INTERVAL=1 |
| 184 |
|
|
|
| 185 |
|
|
# Drop when illegal SSH login username: |
| 186 |
|
|
# (default: "DROP_SSH_ILLEGALUSER=1") |
| 187 |
|
|
[ -z "$DROP_SSH_ILLEGALUSER" ] && DROP_SSH_ILLEGALUSER=1 |
| 188 |
|
|
|
| 189 |
|
|
# Drop when FTP login failed: |
| 190 |
|
|
# (default: "DROP_FTP_FAILEDLOGIN=1") |
| 191 |
|
|
[ -z "$DROP_FTP_FAILEDLOGIN" ] && DROP_FTP_FAILEDLOGIN=1 |
| 192 |
|
|
|
| 193 |
|
|
# Log address dropping to the system log: |
| 194 |
|
|
# (default: "LOG_DROPPED=1") |
| 195 |
|
|
[ -z "$LOG_DROPPED" ] && LOG_DROPPED=1 |
| 196 |
|
|
|
| 197 |
|
|
# Pretend operation(s) (parse only): |
| 198 |
|
|
# (default: "PRETEND=0") |
| 199 |
|
|
[ -z "$PRETEND" ] && PRETEND=0 |
| 200 |
|
|
|
| 201 |
|
|
#--------------------------------------------------------------------- |
| 202 |
|
|
#- Early exit conditions: |
| 203 |
|
|
|
| 204 |
|
|
if [ -z "$SCANLOG" ] || [ ! -f "$SCANLOG" ]; then |
| 205 |
|
|
logmessage "ERROR: No log file to scan. Nothing to do for me." |
| 206 |
|
|
end 1 |
| 207 |
|
|
fi |
| 208 |
|
|
|
| 209 |
|
|
if [ $SEEKSTART != 1 ] && [ $LOGFOLLOW == 0 ]; then |
| 210 |
|
|
logmessage "ERROR: No seek, no follow. Nothing to do for me." |
| 211 |
|
|
end 1 |
| 212 |
|
|
fi |
| 213 |
|
|
|
| 214 |
|
|
#--------------------------------------------------------------------- |
| 215 |
|
|
|
| 216 |
|
|
# Flag for marking the first run: |
| 217 |
|
|
FirstRun=1 |
| 218 |
|
|
|
| 219 |
|
|
while [ -e $SCANLOG ]; do |
| 220 |
|
|
|
| 221 |
|
|
#LogSize=`du -b $SCANLOG | cut -f1` |
| 222 |
|
|
LogSize=$(stat -c %s $SCANLOG) |
| 223 |
|
|
|
| 224 |
|
|
if [ "$FirstRun" == 1 ]; then |
| 225 |
|
|
if [ "$SEEKSTART" == 1 ]; then |
| 226 |
|
|
logmessage "Reading '$SCANLOG' from start. File size is '$LogSize' bytes." |
| 227 |
|
|
else |
| 228 |
|
|
OldLogSize=$LogSize |
| 229 |
|
|
fi |
| 230 |
|
|
fi |
| 231 |
|
|
|
| 232 |
|
|
if ((LogSize > OldLogSize)); then |
| 233 |
|
|
|
| 234 |
|
|
tail --bytes=$[LogSize - OldLogSize] $SCANLOG | \ |
| 235 |
|
|
while read LogFileLine; do |
| 236 |
|
|
|
| 237 |
rabit |
1.2 |
DateTime=`echo "\$LogFileLine" | awk -F' ' '{ print $1 " " $2 " " $3 }'` |
| 238 |
|
|
LogFileMsg=`echo "\$LogFileLine" | awk -F' ' '{ $1=""; $2=""; $3=""; print $0 }'` |
| 239 |
|
|
|
| 240 |
rabit |
1.1 |
case "$LogFileLine" in |
| 241 |
|
|
|
| 242 |
|
|
($MatchP1) |
| 243 |
rabit |
1.2 |
Username=`echo "\$LogFileMsg" | cut -d' ' -f8` |
| 244 |
|
|
IP=`echo "\$LogFileMsg" | cut -d' ' -f10` |
| 245 |
rabit |
1.1 |
logmessage "SSH: illegal login as '$Username' from '$IP' at '$DateTime'." |
| 246 |
|
|
[ "$DROP_SSH_ILLEGALUSER" == 1 ] && dropaddress $IP |
| 247 |
|
|
;; |
| 248 |
|
|
|
| 249 |
|
|
($MatchN2) |
| 250 |
|
|
;; |
| 251 |
|
|
|
| 252 |
|
|
($MatchP2) |
| 253 |
rabit |
1.2 |
Username=`echo "\$LogFileMsg" | cut -d' ' -f9` |
| 254 |
|
|
IP=`echo "\$LogFileMsg" | cut -d' ' -f11` |
| 255 |
rabit |
1.1 |
logmessage "SSH: failed password for '$Username' from '$IP' at '$DateTime'." |
| 256 |
|
|
dropaddress $IP |
| 257 |
|
|
;; |
| 258 |
|
|
|
| 259 |
|
|
($MatchN3) |
| 260 |
|
|
;; |
| 261 |
|
|
|
| 262 |
|
|
($MatchP3) |
| 263 |
rabit |
1.2 |
Username=`echo "\$LogFileMsg" | cut -d' ' -f11` |
| 264 |
|
|
IP=`echo "\$LogFileMsg" | cut -d' ' -f13` |
| 265 |
rabit |
1.1 |
logmessage "SSH: incorrect password for '$Username' from '$IP' at '$DateTime'." |
| 266 |
|
|
dropaddress $IP |
| 267 |
|
|
;; |
| 268 |
|
|
|
| 269 |
|
|
($MatchFTP_P1) |
| 270 |
rabit |
1.2 |
Address=`echo "\$LogFileMsg" | cut -d' ' -f10` |
| 271 |
|
|
Username=`echo "\$LogFileMsg" | cut -d' ' -f11` |
| 272 |
rabit |
1.1 |
Address=${Address/,} |
| 273 |
|
|
IP=$(resolveip -s $Address) |
| 274 |
|
|
logmessage "FTP: failed login as '$Username' from '$IP' at '$DateTime'." |
| 275 |
|
|
[ "$DROP_FTP_FAILEDLOGIN" == 1 ] && dropaddress $IP |
| 276 |
|
|
;; |
| 277 |
|
|
|
| 278 |
|
|
esac |
| 279 |
|
|
done |
| 280 |
|
|
|
| 281 |
|
|
elif ((OldLogSize > LogSize)); then |
| 282 |
|
|
logmessage "'$SCANLOG' has been truncated. New file size is '$LogSize' bytes." |
| 283 |
|
|
fi |
| 284 |
|
|
|
| 285 |
|
|
OldLogSize=$LogSize |
| 286 |
|
|
|
| 287 |
|
|
[ "$LOGFOLLOW" != 1 ] && end |
| 288 |
|
|
|
| 289 |
|
|
[ "$FirstRun" == 1 ] && [ "$LOGFOLLOW" == 1 ] && \ |
| 290 |
|
|
logmessage "Following. Scanning '$SCANLOG' every '$INTERVAL' second(s)." |
| 291 |
|
|
|
| 292 |
|
|
# First run just ended: |
| 293 |
|
|
FirstRun=0 |
| 294 |
|
|
|
| 295 |
|
|
# Make the defined pause: |
| 296 |
|
|
sleep $INTERVAL |
| 297 |
|
|
done |
| 298 |
|
|
|
| 299 |
|
|
#--------------------------------------------------------------------- |
Parent Directory
| 
Revision Log
