Provided by: horst_4.2-1build1_amd64 
NAME
horst - Highly Optimized Radio Scanning Tool
SYNOPSIS
horst [-h] [-q] [-D] [-i interface] [-t sec] [-d ms] [-b bytes] [-s] [-u] [-C] [-c IP] [-p
port] [-o file] [-X name] [-x command] [-e mac] [-f pkt_name] [-m mode]
DESCRIPTION
horst is a small, lightweight IEEE802.11 wireless LAN analyzer with a text interface. Its
basic function is similar to tcpdump, Wireshark or Kismet, but it's much smaller and shows
different, aggregated information which is not easily available from other tools. It is
mainly targeted at debugging wireless LANs with a focus on ad-hoc (IBSS) mode in larger
mesh networks. It can be useful to get a quick overview of what's going on on all wireless
LAN channels and to identify problems.
• Shows signal values per station.
• Calculates channel utilization ("usage") by adding up the amount of time the packets
actually occupy the medium.
• "Spectrum Analyzer" shows signal levels and usage per channel.
• Text-based "graphical" packet history, with signal, packet type and physical rate
• Shows all stations per ESSID and the live TSF per node as it is counting.
• Detects IBSS "splits" (same ESSID but different BSSID - this is a common driver
problem).
• Statistics of packets/bytes per physical rate and per packet type.
• Has some support for mesh protocols (OLSR and batman).
• Can filter specific packet types, source MAC addresses or BSSIDs.
• Client/server support for monitoring on remote nodes.
• Can be controlled via a named pipe.
OPTIONS
-h Show summary of options.
-q Quiet mode. Don't show user interface. This is only useful in conjunction when
running in server mode (-C) or writing to a file (-o).
-D Show lot's of debugging output, including a full package dump. Only available when
compiled with DEBUG=1.
-i intf
Operate on given network interface instead of the default "wlan0". Note that the
interface is assumed to be in monitor mode already. See MONITOR MODE below for more
information about preparing the network interface.
-t sec Timeout (remove) nodes after not receiving packets from them for this time in
seconds (default: 60 sec).
-d ms Display update interval. The default value of 100ms can be increased to reduce CPU
load caused by redrawing the screen.
-b bytes
Receive buffer size. The receive buffer size can be set to tune memory consumption
and reduce lost packets under load.
-s Show a poor mans "spectrum analyzer". The same can be achieved by running horst as
normal and pressing the button 's' (Spec); then 'c' (Chan) and 'a' (Automatically
change channel).
-u Upper channel limit for the automatic channel change.
-C Allow client connections. Server mode. Only one client connection is supported at
the moment (default: off).
-c IP Connect to a horst instance running in server-mode at the specified IP address.
-p port
Use the specified port (default: 4444) for client/server connections.
-o filename
Write a information about each received packet into file. Note that you can send to
STDOUT by using -o /dev/stdout. See OUTPUT FILE FORMAT below.
-X Accept control commands on a named pipe (default /tmp/horst).
-Xname Accept control commands on a named pipe with given name or set pipe name used with
-x.
-x command
Send control command to another horst process who was started with -X and then
exit. Multiple commands can be concatenated with ':'. Currently implemented
commands are:
pause Pause horst processing
resume Resume horst processing
channel=X Set channel channel number
channel_auto=X Automatically change channels (1 or 0)
channel_dwell=X Set channel dwell time when automatically changing channel
(ms)
channel_upper=X Set max channel when automatically changing channel
outfile=X Write to outfile named X.
If the file is already open, it is cleared and re-openend.
If filename is not specified ("outfile=") any existing file
is closed and no file is written.
-e MAC Filter all MAC addresses except these, to show only packets originating from the
specified MAC addresses. This option can be specified multiple times.
-f pkt_type
Filter all packets except these. This option can be specified multiple times. For
valid packet names see NAMES AND ABBREVIATIONS below.
-m (AP|STA|ADH|PRB|WDS|UNKNOWN)
Only show/include packets and nodes of this mode. Note that the mode is infered by
the information of packets we received and it may take some time until a node is
properly classified. This option can be specified multiple times.
TEXT USER INTERFACE
The ncurses-based text interface tries to display a lot of information, so it may look
confusing at first. Below we describe the different screens and options.
Main screen
The initial (main) screen is split into three parts. The upper area shows a list of
aggregated "node" information, the most useful information about each sender which
was discovered, one per line:
/ "Spinner" to show activity
Pk Count of packets
Re% Percentage of Re-sent frames
CH Channel
Sig Signal value (RSSI) in dBm
RAT Physical data rate
TRANSMITTER MAC address of sender
MODE Operating Mode (AP, AHD, PRB, STA, WDS), see "NAMES AND
ABBREVIATIONS"
ENCR Encryption (WPA1, WPA2, WEP)
ESSID ESSID
INFO Additional info like "BATMAN", IP address...
The lower area shows a scrolling list of packets as they come in:
CH Channel
Sig Signal value (RSSI) in dBm
RAT Physical data rate
TRANSMITTER MAC address of sender
BSSID BSSID
TYPE Packet type, see "NAMES AND ABBREVIATIONS"
INFO Additional info like ESSID, TFS, IP address...
The lower right box shows bar graphs for:
Signal of last received packet in green
bps Bits per second of all received packets
Usage Percentage of channel use
The lower edge is the menu and status bar, it shows which keys to press for other
screens. The status shows ">" when horst is running or "=" when it is paused, then
"F" when any kind of filter is active, the Channel, the monitor interface in use
and the time.
Pause ('p' or <space>)
Can be used to pause/resume horst. When horst is paused it will loose packets
received in the mean time.
Reset ('r')
Clears all history and aggregated statistical data.
History ('h')
The history screen scrolls from right to left and shows a bar for each packet
indicating the signal level. In the line below that, the packet type is indicated
by one character (See NAMES AND ABBREVIATIONS below) and the rough physical data
rate is indicated below that in blue.
ESSID ('e')
The ESSID screen groups information by ESSID and shows the mode (AP, IBSS), the MAC
address of the sender, the BSSID, the TSF, the beacon interval, the channel, the
signal, a "W" when encrytoion is used and the IP address if known.
Statistics ('a')
The statistics screen groups packets by physical rate and by packet type and shows
other kinds of aggregated and statistical information based on packets.
Spectrum Analyzer ('s')
The "poor mans spectrum analyzer" screen is only really useful when horst is
started with the -s option or the "Automatically change channel" option is selected
in the "Chan" settings.
It shows the available channels horizontally and vertical bars for each channel:
Signal in green
Physical rate in blue
Channel usage in orange/brown
By pressing the 'n' key, the display can be changed to show only the average signal
level on each channel and the last 4 digits of the MAC address of the individual
nodes at the level (height) they were received. This can give a quick graphical
overview of the distance of nodes.
Filters ('f')
This configuration dialog can be used to define the active filters.
Channel Settings ('c')
This configuration dialog can be used to change the channel changing behaviour of
horst or to change to a different channel manually.
Sort ('o')
Only active in the main screen, can be used to sort the node list in the upper area
by Signal, Time, BSSID or Channel.
NAMES AND ABBREVIATIONS
802.11 standard frames
Management frames:
a ASOCRQ Association request
A ASOCRP Associaion response
a REASRQ Reassociation request
A REASRP Reassociation response
p PROBRQ Probe request
P PROBRP Probe response
T TIMING Timing Advertisement
B BEACON Beacon
t ATIM ATIM
D DISASC Disassociation
u AUTH Authentication
U DEAUTH Deauthentication
C ACTION Action
c ACTNOA Action No Ack
Control frames:
w CTWRAP Control Wrapper
b BACKRQ Block Ack Request
B BACK Block Ack
s PSPOLL PS-Poll
R RTS RTS
C CTS CTS
K ACK ACK
f CFEND CF-End
f CFENDK CF-End + CF-Ack
Data frames:
D DATA Data
F DCFACK Data + CF-Ack
F DCFPLL Data + CF-Poll
F DCFKPL Data + CF-Ack + CF-Poll
n NULL Null (no data)
f CFACK CF-Ack (no data)
f CFPOLL CF-Poll (no data)
f CFCKPL CF-Ack + CF-Poll (no data)
Q QDATA QoS Data
F QDCFCK QoS Data + CF-Ack
F QDCFPL QoS Data + CF-Poll
F QDCFKP QoS Data + CF-Ack + CF-Poll
N QDNULL QoS Null (no data)
f QCFPLL QoS CF-Poll (no data)
f QCFKPL QoS CF-Ack + CF-Poll (no data)
* BADFCS Bad frame checksum
Packet types
Similar to 802.11 frames above but higher level and as a bit field (types can
overlap, e.g. DATA + IP) and including more information, like IP, ARP, BATMAN,
OLSR...
CTRL 0x000001 WLAN Control frame
MGMT 0x000002 WLAN Management frame
DATA 0x000004 WLAN Data frame
BADFCS 0x000008 WLAN frame checksum (FCS) bad
BEACON 0x000010 WLAN beacon frame
PROBE 0x000020 WLAN probe request or response
ASSOC 0x000040 WLAN associaction request/response frame
AUTH 0x000080 WLAN authentication frame
RTSCTS 0x000100 WLAN RTS or CTS
ACK 0x000200 WLAN ACK or BlockACK
NULL 0x000400 WLAN NULL Data frame
QDATA 0x000800 WLAN QoS Data frame (WME/WMM)
ARP 0x001000 ARP packet
IP 0x002000 IP packet
ICMP 0x004000 IP ICMP packet
UDP 0x008000 IP UDP
TCP 0x010000 IP TCP
OLSR 0x020000 OLSR protocol
BATMAN 0x040000 BATMAND Layer3 or BATMAN-ADV Layer 2 frame
MESHZ 0x080000 MeshCruzer protocol
Operating modes
Bit field of operating mode type which is infered from received packets. Modes may
overlap, i.e. it is common to see STA and PRB at the same time.
AP 0x01 Access Point (AP)
ADH 0x02 Ad-hoc node
STA 0x04 Station (AP client)
PRB 0x08 Sent PROBE requests
WDS 0x10 WDS or 4 Address frames
UNKNOWN 0x20 Unknown e.g. RTS/CTS or ACK
MONITOR MODE
horst should work with any wireleass LAN card and driver which supports monitor mode, with
either "prism2" or "radiotap" headers. This includes most modern mac80211-based drivers.
You have to put your card in monitor mode and set the channel manually before you start
horst. Usually this has to be done as root.
Note that depending on the wireless driver capabilities and versions, signal values and
ranges may be different. Also, if the monitor interface is added to an existing interface,
the driver does not allow the channel to be changed.
Using iw:
iw wlan0 interface add mon0 type monitor
or
sudo iw wlan1 set type monitor
sudo iw wlan1 set channel 6
Using iwconfig:
iwconfig wlan0 mode monitor
iwconfig wlan0 channel 1
ifconfig wlan0 up
Using madwifi:
wlanconfig wlan0 create wlandev wifi0 wlanmode monitor
Using hostap:
iwconfig wlan0 mode monitor
iwpriv wlan0 monitor_type 1
OUTPUT FILE FORMAT
The format of the output file (-o flag) is a comma separated list of the following fields
in the following order, one packet each line.
packet_type
802.11 MAC packet type name as defined in the section "NAMES AND ABBREVIATIONS".
wlan_src
Source MAC address
wlan_dst
Destination MAC address
wlan_bssid
BSSID
pkt_types
Higher level packet name as defined in section "NAMES AND ABBREVIATIONS".
phy_signal
Signal strength in dBm
phy_noise
Noise in dBm (always 0)
phy_snr
Signal to Noise ratio in dB (always 0, redundant)
wlan_len
Packet length (MAC)
phy_rate
Physical data rate
phy_freq
Received while tuned to this frequency.
wlan_tsf
TFS timer value
wlan_essid
ESSID, network name
wlan_mode
Operating modes as defined in "NAMES AND ABBREVIATIONS".
wlan_channel
Channel number
wlan_wep
Encryption in use
wlan_wpa
WPA1 Encryption in use
wlan_rsn
RSN (WPA2) Encryption in use
ip_src IP source address (if available)
ip_dst IP destionation address (if available)
olsr_type
OLSR message type (if applicable)
olsr_neigh
OLSR number of neighbours (if applicable)
SEE ALSO
tcpdump(1), wireshark(1), kismet(1), README, http://br1.einfach.org/tech/horst
AUTHOR
horst was written by Bruno Randolf <br1@einfach.org>.
This manual page was written by Antoine Beaupré <anarcat@debian.org>, for the Debian
project (and may be used by others).
September 23, 2014 HORST(8)