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Operating System: Kali Rolling 2016.2 i686, PWK VM with VMware Fusion

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Purpose: Set up DHCP server in Kali

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Reference: https://www.offensive-security.com/metasploit-unleashed/karmetasploit-configuration/

===============
Steps to Reproduce:

1. Acquire karma.txt file
   root@kali:~# wget https://www.offensive-security.com/wp-content/uploads/2015/04/karma.rc_.txt
   --2016-09-27 14:54:22-- https://www.offensive-security.com/wp-content/uploads/2015/04/karma.rc_.txt
   Resolving www.offensive-security.com (www.offensive-security.com)
   ... snip ...

2. Install DHCP server
   root@kali:~# apt-get install isc-dhcp-server
   Reading package lists... Done
   Building dependency tree
   Reading state information... Done
   ... snip ...

3. Edit /etc/dhcp/dhcp.conf as follows
   root@kali:~# cat /etc/dhcp/dhcpd.conf

   dhcpd.conf

   #

   Sample configuration file for ISC dhcpd

   #

option domain-name-servers 10.0.0.1;

default-lease-time 60;
max-lease-time 72;

ddns-update-style none;

authoritative;

log-facility local7;

subnet 10.0.0.0 netmask 255.255.255.0 {
range 10.0.0.100 10.0.0.254;
option routers 10.0.0.1;
option domain-name-servers 10.0.0.1;
}

4. Install required ruby gems
   root@kali:~# gem install activerecord sqlite3
   Successfully installed activerecord-5.0.0.1
   Parsing documentation for activerecord-5.0.0.1
   Done installing documentation for activerecord after 5 seconds
   ... snip ...
   note: the guide above says to install sqlite3-ruby, which has since been renamed.

5. Start airmon-ng
   root@kali:~# airmon-ng start wlan0
   PHY Interface Driver Chipset
   phy0 wlan0 ath9k_htc Atheros Communications, Inc. AR9271 802.11n
   (mac80211 monitor mode vif enabled for [phy0]wlan0 on [phy0]wlan0mon)
   (mac80211 station mode vif disabled for [phy0]wlan0)

6. Start airbase-ng
   root@kali:~# airbase-ng -P -C 30 -e "U R PWND" -v wlan0mon
   15:11:21 Created tap interface at0
   15:11:21 Trying to set MTU on at0 to 1500
   15:11:21 Trying to set MTU on wlan0mon to 1800
   ... snip ...

7. Put up at0 interface
   root@kali:~# ifconfig at0 up 10.0.0.1 netmask 255.255.255.0

8. Try to start dhcpd (FAILURE)
   root@kali:~# dhcpd -cf /etc/dhcp/dhcpd.conf at0
   Internet Systems Consortium DHCP Server 4.3.4
   Copyright 2004-2016 Internet Systems Consortium.
   All rights reserved.
   For info, please visit https://www.isc.org/software/dhcp/
   Config file: /etc/dhcp/dhcpd.conf
   Database file: /var/lib/dhcp/dhcpd.leases
   PID file: /var/run/dhcpd.pid
   Can't open lease database /var/lib/dhcp/dhcpd.leases: No such file or directory --
   check for failed database rewrite attempt!
   Please read the dhcpd.leases manual page if you
   don't know what to do about this.
   If you think you have received this message due to a bug rather
   than a configuration issue please read the section on submitting
   bugs on either our web page at www.isc.org or in the README file
   before submitting a bug. These pages explain the proper
   process and the information we find helpful for debugging..
   exiting.

9. Create required file
   root@kali:~# touch /var/lib/dhcp/dhcpd.leases

10. Start dhcpd (SUCCESS)
    root@kali:~# dhcpd -cf /etc/dhcp/dhcpd.conf at0
    Internet Systems Consortium DHCP Server 4.3.4
    Copyright 2004-2016 Internet Systems Consortium.
    All rights reserved.
    For info, please visit https://www.isc.org/software/dhcp/
    Config file: /etc/dhcp/dhcpd.conf
    Database file: /var/lib/dhcp/dhcpd.leases
    PID file: /var/run/dhcpd.pid
    Wrote 0 leases to leases file.
    Listening on LPF/at0/00:c0:ca:82:d9:63/10.0.0.0/24
    Sending on LPF/at0/00:c0:ca:82:d9:63/10.0.0.0/24
    Sending on Socket/fallback/fallback-net

11. Check running processes
    root@kali:~# ps aux |grep dhcpd
    root 3486 0.0 0.2 13904 5884 ? Ss 15:12 0:00 dhcpd -cf /etc/dhcp/dhcpd.conf at0
    root 3489 0.0 0.0 4636 788 pts/2 S+ 15:12 0:00 grep dhcpd

Closing as this is by design.

In step 8, with the error:
"""
Can't open lease database /var/lib/dhcp/dhcpd.leases: No such file or directory --
check for failed database rewrite attempt!
Please read the dhcpd.leases manual page if you
don't know what to do about this.
""

Man page: https://linux.die.net/man/5/dhcpd.leases

"""
When dhcpd is first installed, there is no lease database. However, dhcpd requires that a lease database be present before it will start. To make the initial lease database, just create an empty file called /var/lib/dhcpd/dhcpd.leases. You can do this with:

touch /var/lib/dhcpd/dhcpd.leases

"""