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@niltonvasques

niltonvasques/knockd_generator.sh

Created October 13, 2019 01:18
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  1. niltonvasques created this gist Oct 13, 2019.
    48 changes: 48 additions & 0 deletions knockd_generator.sh
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,48 @@
    #!/bin/bash

    PINS=$1
    HOSTNAME=$2
    USERNAME=$3

    PINDIPS=`shuf -i 1024-65534 -n $PINS`
    OUTLOCK="knockd.conf"

    # CHECK SYNTAX
    if [ "$#" -ne 3 ]; then
    echo "Syntax Error!"
    echo "Syntax: $0 <number of pins> <hostname/ip> <username to login>"
    exit
    fi

    # CREATE FILES
    touch $OUTLOCK

    # GENERATE SERVER CONFIGURATION
    echo "GENERATING KNOCKd CONFIG FILE"
    echo "copy knockd.conf to /etc/knockd.conf"
    echo "[option]" > $OUTLOCK
    echo " UseSyslog" >> $OUTLOCK
    echo "" >> $OUTLOCK
    echo "[KnockSSH]" >> $OUTLOCK
    for x in `seq 1 $PINS`
    do
    PIN=$(echo $PINDIPS | cut -d " " -f $x)
    SEQUENCE="$SEQUENCE,$PIN"
    done
    SEQUENCE=$(echo $SEQUENCE | sed -r 's/^.{1}//')
    echo " sequence = $SEQUENCE" >> $OUTLOCK
    echo " tcpflags = syn" >> $OUTLOCK
    echo " seq_timeout = 15" >> $OUTLOCK
    echo " start_command = /sbin/iptables -I INPUT -s %IP% -p tcp --dport 22 -j ACCEPT" >> $OUTLOCK
    echo " cmd_timeout = 10" >> $OUTLOCK
    echo " stop_command = /sbin/iptables -D INPUT -s %IP% -p tcp --dport 22 -j ACCEPT" >> $OUTLOCK
    echo "" >> $OUTLOCK

    echo " "

    # GENERATE SERVER ACCESS COMMAND
    SEQUENCE=$(echo $SEQUENCE | sed -r 's/,/ /g')
    echo "USE THE COMMAND BELLOW TO OPEN THE WINDOW AND ACCESS THE SERVER:"
    echo " "
    echo "for x in $SEQUENCE; do nmap -Pn --host_timeout 201 --max-retries 0 -p "'$x'" $HOSTNAME; done
    && ssh $USERNAME@$HOSTNAME"