1arpon(8)                    System Manager's Manual                   arpon(8)
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3
4

NAME

6       ArpON - ARP handler inspection
7

IMPORTANT NOTICE

9       Since  ArpON  3.0-ng  (next  generation), ArpON has been rewritten from
10       scratch, therefore all the old versions of ArpON (lower of 3.0-ng)  are
11       deprecated.  Please  upgrade  all installations of ArpON and read care‐
12       fully the documentation specified below and this man page of ArpON.
13

SYNOPSIS

15       arpon [OPTIONS] [SARPI DARPI HARPI]
16

DESCRIPTION

18       ArpON (ARP handler inspection) is a Host-based solution that  make  the
19       ARP  standardized protocol secure in order to avoid the Man In The Mid‐
20       dle (MITM) attack through the ARP spoofing, ARP cache poisoning or  ARP
21       poison routing attack.
22
23       This is possible using three kinds of anti ARP spoofing techniques:
24
25       1) SARPI (Static ARP Inspection) for the statically configured networks
26       without DHCP;
27       2) DARPI (Dynamic ARP Inspection) for the dynamically  configured  net‐
28       works with DHCP;
29       3)  HARPI  (Hybrid  ARP  Inspection) for the statically and dynamically
30       configured networks with DHCP.
31
32       The goal of ArpON is therefore to provide a secure and  efficient  net‐
33       work  daemon that provides the SARPI, DARPI and HARPI anti ARP spoofing
34       technique, thus making the ARP standardized protocol  secure  from  any
35       foreign intrusion.
36
37       ArpON  sets  of  policies  in  the  ARP cache for all the static and or
38       dynamic entries matching  the  specified  network  interface  (or  that
39       matching  the  several specified network interfaces if run concurrently
40       several daemons of ArpON for different network interfaces), through the
41       run of SARPI, DARPI or HARPI anti ARP spoofing technique.
42
43       ArpON have to be run with the root privileges. ArpON have to be config‐
44       ured using command-line options and a configuration file. ArpON reloads
45       the  configuration  of  the specified network interface and rereads its
46       configuration file when it receives a hangup signal (SIGHUP) by execut‐
47       ing  itself  with the name and options it was started with. ArpON exits
48       correctly when it receives an interrupt signal (SIGINT) or  a  termina‐
49       tion signal (SIGTERM).
50

IMPORTANT NOTE

52       The ArpON daemon sets two fundamental kernel network parameters via the
53       sysctl interface on the specified network interface:
54
55       1) The arp_ignore kernel parameter of the specified  network  interface
56       is  always setted to 8 by ArpON. This is done to disable, in the speci‐
57       fied network interface of the Operating System, the sending of the  ARP
58       replies  in  response  to received ARP requests for all local addresses
59       (the ARP replies on the specified network interface, will  be  sent  by
60       ArpON instead of the Operating System).
61
62       2)  The  arp_accept kernel parameter of the specified network interface
63       is always setted to 0 by ArpON. This is done to disable, in the  speci‐
64       fied network interface of the Operating System, the creating of the new
65       IP entries in the ARP cache triggered by the unsolicited and gratuitous
66       ARP requests and replies (the IP entries in the ARP cache on the speci‐
67       fied network interface, will be created or updated by ArpON  as  static
68       or dynamic IP entries instead of the Operating System).
69
70       The   ArpON  daemon  restores  the  previously  values  read  from  the
71       arp_ignore and arp_accept kernel parameters of  the  specified  network
72       interface  when  it receives an interrupt signal (SIGINT) or a termina‐
73       tion signal (SIGTERM). Remember to restore the values of the arp_ignore
74       and  arp_accept  kernel  parameters  of the specified network interface
75       (the default values are 0 for both), if you have terminated  the  ArpON
76       daemon with other signals, e.g. kill signal (SIGKILL).
77

OPTIONS SUMMARY

79       The available options are:
80
81       GENERAL OPTIONS
82
83       -d (--daemon)
84              Daemonize the ArpON.
85
86       -i (--interface) <interface>
87              Use the specified network interface.
88
89       SARPI 'STATIC ARP INSPECTION' OPTION
90
91       SARPI  anti ARP spoofing technique manages and sets the policies in the
92       ARP cache only for all the static entries matching the  specified  net‐
93       work  interface,  in order to avoid the Man In The Middle (MITM) attack
94       through the ARP spoofing, ARP cache poisoning or  ARP  poison  routing.
95       Therefore  SARPI  is  an  optimal choice in those statically configured
96       networks without DHCP. SARPI sets these policies:
97
98       1) CLEAN: SARPI cleans from the ARP cache only all the entries matching
99       the specified network interface, that are present or not present in the
100       configuration file;
101       2) UPDATE: SARPI updates in the ARP cache only all the  static  entries
102       matching  the specified network interface, that are present in the con‐
103       figuration file;
104       3) REFRESH: SARPI refreshes in the ARP cache only a static entry match‐
105       ing  the specified network interface, that is present in the configura‐
106       tion file;
107       4) ALLOW: SARPI sets up in the ARP cache only a dynamic entry  matching
108       the  specified network interface, that is not present in the configura‐
109       tion file.
110
111       Therefore SARPI requires a specified network interface and the specifi‐
112       cation  in  the  configuration  file  of the ARP cache only for all the
113       static entries matching the specified network interface.
114
115       -S (--sarpi)
116              Run SARPI anti ARP spoofing technique.
117
118       DARPI 'DYNAMIC ARP INSPECTION' OPTION
119
120       DARPI anti ARP spoofing technique manages and sets the policies in  the
121       ARP  cache only for all the dynamic entries matching the specified net‐
122       work interface, in order to avoid the Man In The Middle  (MITM)  attack
123       through  the  ARP  spoofing, ARP cache poisoning or ARP poison routing.
124       Therefore DARPI is an optimal choice in  those  dynamically  configured
125       networks with DHCP. DARPI sets these policies:
126
127       1) CLEAN: DARPI cleans from the ARP cache only all the entries matching
128       the specified network interface;
129       2) ALLOW: DARPI sets up in the ARP cache only a dynamic entry  matching
130       the specified network interface;
131       3) DENY: DARPI cleans up from the ARP cache only a dynamic entry match‐
132       ing the specified network interface.
133
134       Therefore DARPI requires a specified network interface and  it  doesn't
135       requires  any  specification in the configuration file of the ARP cache
136       only for all the dynamic entries matching the specified network  inter‐
137       face.
138
139       -D (--darpi)
140              Run DARPI anti ARP spoofing technique.
141
142       HARPI 'HYBRID ARP INSPECTION' OPTION
143
144       HARPI  anti ARP spoofing technique manages and sets the policies in the
145       ARP cache for both all the static  and  dynamic  entries  matching  the
146       specified  network  interface,  in order to avoid the Man In The Middle
147       (MITM) attack through the ARP spoofing, ARP cache poisoning or ARP poi‐
148       son  routing.  Therefore HARPI is an optimal choice in those statically
149       and dynamically configured networks with DHCP. HARPI sets and  combines
150       these policies of the SARPI and DARPI:
151
152       1) CLEAN: HARPI cleans from the ARP cache only all the entries matching
153       the specified network interface, that are present or not present in the
154       configuration file;
155       2)  UPDATE:  HARPI updates in the ARP cache only all the static entries
156       matching the specified network interface, that are present in the  con‐
157       figuration file;
158       3) REFRESH: HARPI refreshes in the ARP cache only a static entry match‐
159       ing the specified network interface, that is present in the  configura‐
160       tion file;
161       4)  ALLOW: HARPI sets up in the ARP cache only a dynamic entry matching
162       the specified network interface, that is not present in the  configura‐
163       tion file;
164       5) DENY: HARPI cleans up from the ARP cache only a dynamic entry match‐
165       ing the specified network interface, that is not present in the config‐
166       uration file.
167
168       Therefore  HARPI requires a specified network interface, the specifica‐
169       tion in the configuration file of the ARP cache only for all the static
170       entries  matching  the  specified network interface; instead it doesn't
171       requires any specification in the configuration file of the  ARP  cache
172       only  for all the dynamic entries matching the specified network inter‐
173       face.
174
175       -H (--harpi)
176              Run HARPI anti ARP spoofing technique.
177
178       STANDARD OPTIONS
179
180       -v (--version)
181              Print the version and exit.
182
183       -h (--help)
184              Print the help screen and exit.
185

FILES

187       The available files are:
188
189       /etc/arpon.conf
190              The configuration file contains the configuration data of  ArpON
191              and  it  is  used  when run the SARPI or HARPI anti ARP spoofing
192              technique, for the specification in the ARP cache only  for  all
193              the  static entries matching the specified network interface (or
194              that matching the several specified network  interfaces  if  run
195              concurrently  several  daemons  of  ArpON  for different network
196              interfaces). This file should be writable by root only but it is
197              recommended (though not necessary) that it be world-readable.
198
199       /var/log/arpon.log
200              The  log  file contains the log data of ArpON. If there are sev‐
201              eral daemons of ArpON running concurrently for different network
202              interfaces,  this  contains  the  log data of all the daemons of
203              ArpON. This file should be readable only by root, and  need  not
204              be readable by anyone else.
205
206       /var/run/arpon.pid
207              The pid file contains the process ID of ArpON. If there are sev‐
208              eral daemons of ArpON running concurrently for different network
209              interfaces,  this  contains  the  process  ID of the one started
210              last. The content of this file  is  not  sensitive;  it  can  be
211              world-readable.
212

EXAMPLES

214       These  examples  shows  how to use all three kinds of anti ARP spoofing
215       techniques.
216
217       In the same host, we have three network interfaces with different  sub‐
218       net  classes  and  we  would  set  the ARP cache for all the static and
219       dynamic entries matching the eth0, wlan0 and eth1  network  interfaces.
220       This scenario requires the run concurrently of three daemons of ArpON:
221
222       SARPI 'STATIC ARP INSPECTION' EXAMPLE
223
224       The  eth0  network interface has the 192.168.1.2/24 IP address. We have
225       only three static entries of the ARP cache:
226
227       1) 192.168.1.1 at 58:ac:78:10:b9:77;
228       2) 192.168.1.3 at d4:be:d9:fe:8b:45;
229       3) 192.168.1.4 at 90:94:e4:bb:1c:10.
230
231       and we have no dynamic entries of the ARP cache. This is the ideal case
232       where  we  have to use the SARPI anti ARP spoofing technique, therefore
233       specify in the configuration file of the ARP cache only all the  static
234       entries matching the eth0 network interface:
235
236              $ sudo nano /etc/arpon.conf
237
238       Therefore:
239
240              #
241              # ArpON configuration file.
242              #
243              # See the arpon(8) man page for details.
244              #
245
246              #
247              # Static entries matching the eth0 network interface:
248              #
249              # First static entry:
250              192.168.1.1     58:ac:78:10:b9:77
251              # Second static entry:
252              192.168.1.3     d4:be:d9:fe:8b:45
253              # Third static entry:
254              192.168.1.4     90:94:e4:bb:1c:10
255
256       Daemonize  the  ArpON  and run SARPI anti ARP spoofing technique on the
257       eth0 network interface:
258
259              $ sudo arpon -d -i eth0 -S
260
261       Read the log file:
262
263              $ sudo tail -f /var/log/arpon.log
264
265       Read the pid file:
266
267              $ cat /var/run/arpon.pid
268
269       DARPI 'DYNAMIC ARP INSPECTION' EXAMPLE
270
271       The wlan0 network interface has the 172.16.1.2/24 IP address.  We  have
272       no static entries of the ARP cache, and we have only dynamic entries of
273       the ARP cache. This is the ideal case where we have to  use  the  DARPI
274       anti  ARP  spoofing  technique,  therefore  daemonize the ArpON and run
275       DARPI anti ARP spoofing technique on the wlan0 network interface:
276
277              $ sudo arpon -d -i wlan0 -D
278
279       Read the log file:
280
281              $ sudo tail -f /var/log/arpon.log
282
283       Read the pid file:
284
285              $ cat /var/run/arpon.pid
286
287       HARPI 'HYBRID ARP INSPECTION' EXAMPLE
288
289       The eth1 network interface has the 10.0.1.2/16 IP address. We have only
290       two static entries of the ARP cache:
291
292       1) 10.0.1.1 at 58:ac:78:88:1a:bb;
293       2) 10.0.10.1 at 90:94:e4:7e:f4:59.
294
295       and  we  have  the rest of entries as dynamic entries of the ARP cache.
296       This is the ideal case where we have to use the HARPI anti ARP spoofing
297       technique, therefore specify in the configuration file of the ARP cache
298       only all the static entries matching the eth1 network interface:
299
300              $ sudo nano /etc/arpon.conf
301
302       Therefore:
303
304              #
305              # ArpON configuration file.
306              #
307              # See the arpon(8) man page for details.
308              #
309
310              #
311              # Static entries matching the eth0 network interface:
312              #
313              # First static entry:
314              192.168.1.1     58:ac:78:10:b9:77
315              # Second static entry:
316              192.168.1.3     d4:be:d9:fe:8b:45
317              # Third static entry:
318              192.168.1.4     90:94:e4:bb:1c:10
319
320              #
321              # Static entries matching the eth1 network interface:
322              #
323              # First static entry:
324              10.0.1.1        58:ac:78:88:1a:bb
325              # Second static entry:
326              10.0.10.1       90:94:e4:7e:f4:59
327
328       Daemonize the ArpON and run HARPI anti ARP spoofing  technique  on  the
329       eth1 network interface:
330
331              $ sudo arpon -d -i eth1 -H
332
333       Read the log file:
334
335              $ sudo tail -f /var/log/arpon.log
336
337       Read the pid file:
338
339              $ cat /var/run/arpon.pid
340

DOCUMENTATION

342       Please see also the documentation file:
343
344              /usr/share/doc/arpon/index.html
345
346       It contains the retrieving tutorial; the building tutorial; the instal‐
347       lation tutorial; the user tutorial with many  examples  and  scenarios;
348       the development tutorial with the Activity diagrams of the SARPI, DARPI
349       and HARPI anti ARP spoofing technique and with modular source code well
350       commented;  the bug report tutorial that takes you step-by-step through
351       all of the features of ArpON.
352

DEVELOPMENT AND BUGS

354       Please send questions, desirable enhancements, patch, source code  con‐
355       tributions,  problems,  bugs,  etc... to author or via the Bug tracking
356       system, as specified in the documentation file specified above  and  in
357       the official website:
358
359              http://arpon.sourceforge.net
360

AUTHOR

362       ArpON    was    writen    by    Andrea   Di   Pasquale   aka   "spikey"
363       <spikey.it@gmail.com>.
364
366       Copyright (C) 2008-2016 Andrea Di Pasquale <spikey.it@gmail.com>
367       All rights reserved.
368
369       Redistribution and use in source and binary forms, with or without mod‐
370       ification,  are  permitted  provided  that the following conditions are
371       met:
372
373       1. Redistributions of source  code  must  retain  the  above  copyright
374       notice, this list of conditions and the following disclaimer.
375
376       2.  Redistributions  in  binary form must reproduce the above copyright
377       notice, this list of conditions and the  following  disclaimer  in  the
378       documentation and/or other materials provided with the distribution.
379
380       THIS  SOFTWARE  IS  PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
381       IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED  TO,  THE  IMPLIED  WAR‐
382       RANTIES  OF  MERCHANTABILITY  AND  FITNESS FOR A PARTICULAR PURPOSE ARE
383       DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR HIS  RELATIVES  BE  LIABLE
384       FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUEN‐
385       TIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF  SUBSTITUTE
386       GOODS  OR  SERVICES;  LOSS  OF MIND, USE, DATA, OR PROFITS; OR BUSINESS
387       INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
388       CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
389       ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED  OF
390       THE POSSIBILITY OF SUCH DAMAGE.
391

NOTES

393       The  ArpON  daemon  is  completely compatible with the ARP standardized
394       protocol as described in these official RFC documents:
395
396       1. RFC 826:
397              http://tools.ietf.org/html/rfc826
398
399       2. RFC 2131:
400              http://tools.ietf.org/html/rfc2131
401
402       3. RFC 3927:
403              http://tools.ietf.org/html/rfc3927
404
405       4. RFC 5227:
406              http://tools.ietf.org/html/rfc5227
407
408       The ArpON daemon sets the arp_ignore  and  the  arp_accept  fundamental
409       kernel network parameters via the sysctl interface as described in this
410       official kernel document:
411
412       1. IP sysctl:
413              http://www.kernel.org/doc/Documentation/networking/ip-sysctl.txt
414
415
416
417
418ArpON 3.0-ng                    29 January 2016                       arpon(8)
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