dhtest readme
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About the tool
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dhtest - linux dhcp client simulation tool. It can simulate hundreds of dhcp
client from a linux machine. Linux root login is needed because the tool requires
layer2 raw socket for sending and receiving dhcp packets.
Installation
------------
* Download the latest source from github as zip.
Download link - https://github.com/saravana815/dhtest/archive/master.zip
[sargandh@CentOS Desktop]$ unzip dhtest-master.zip
[sargandh@CentOS Desktop]$ cd dhtest-master
[sargandh@CentOS dhtest-master]$ make
gcc -c -o dhtest.o dhtest.c
gcc -c -o functions.o functions.c
gcc dhtest.o functions.o -o dhtest
[sargandh@CentOS dhtest-master]$ ls -lh dhtest
-rwxrwxr-x 1 sargandh sargandh 38K Mar 13 10:47 dhtest
dhtest 1.5 - new 1.5 features supported
-----------------------------------------
* Add option to send DHCP DECLINE packets ('-D' flag)
* Fix potential Segmentation Fault in get_dhinfo() function
* Added dhcp option55 requested parameter list
dhtest 1.4 - till 1.4 features supported
-----------------------------------------
* IP obtaining through DHCP
* Release obtained IP with -r flag
* VLAN
* Broadcast flag support
* DHCP option 50 - Requested IP
* DHCP option 60 - Vendor Class Identifier
* Binding obtained IP for a default timeout of 3600 seconds
* Support of bind timeout with -k flag on command line
* Added DHCP option 51 - Requested lease time from server
* Added DHCP option 12 - Hostname
* Added DHCP option 81 - Fqdn
* Option to send in unicast mode.
* Option to output for nagios.
* Option to change port, patch by Alan Dekok.
* Custom option support - Allows packing of any dhcp option in number/string/hex format
License
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Please see the LICENSE file.
Tool usage examples
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* https://sargandh.wordpress.com/2012/02/23/linux-dhcp-client-simulation-tool/
* custom option examples
dhcp option 82
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[root@CentOS dhtest-1.1]# ./dhtest -m 00:00:00:11:11:11
-c 82,hex,0108476967302f312f30021130303a30303a30303a31313a31313a3131
| || |
| || |Subopt value - 'Gig0/1/0'
| | **************
| Subopt len 8
Opt82 subopt 1
Circuit id
[root@CentOS dhtest-1.1]# ./dhtest -m 00:00:00:11:11:11
-c 82,hex,0108476967302f312f30021130303a30303a30303a31313a31313a3131
| || |
| || |Subopt value - '00:00:00:11:11:11'
| | **************
| Subopt len 17
Opt82 subopt 2
Remote id
dhcp option 60 and 82 (multiple custom options)
-----------------------------------------------
[root@CentOS dhtest-1.1]# ./dhtest -m 00:00:00:11:11:11 -c 60,str,"MSFT 5.0"
-c 82,hex,0108476967302f312f30021130303a30303a30303a31313a31313a3131
* dhcp option55 requested parameter list example
root@ubuntu-16:~/dhtest# ./dhtest -m 00:00:00:11:11:11 -i enp0s3 -l 011C030F060A0B
DHCP discover sent - Client MAC : 00:00:00:11:11:11
DHCP offer received - Offered IP : 10.0.2.16
DHCP request sent - Client MAC : 00:00:00:11:11:11
DHCP ack received - Acquired IP: 10.0.2.16
root@ubuntu-16:~/dhtest#
Tshark output
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Option: (55) Parameter Request List
Length: 7
Parameter Request List Item: (1) Subnet Mask
Parameter Request List Item: (28) Broadcast Address
Parameter Request List Item: (3) Router
Parameter Request List Item: (15) Domain Name
Parameter Request List Item: (6) Domain Name Server
Parameter Request List Item: (10) Impress Server
Parameter Request List Item: (11) Resource Location Server