File: uruk.html

package info (click to toggle)
uruk 20140627-1
  • links: PTS, VCS
  • area: main
  • in suites: jessie, jessie-kfreebsd
  • size: 1,088 kB
  • ctags: 70
  • sloc: sh: 1,770; makefile: 143; xml: 51
file content (508 lines) | stat: -rw-r--r-- 22,510 bytes parent folder | download | duplicates (2)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<!-- Copyright (c) 2013 Joost van Baal-Ilić <joostvb-uruk@mdcc.cx> -->
<head>
<meta name="keywords" content="manual">
<style type="text/css">
/* START aephea.base.css */
body
{ text-align: justify;
margin-left: 0%;
margin-right: 0%;
}
a:link { text-decoration: none; }
a:active { text-decoration: none; }
a:visited { text-decoration: none; }
a:link { color: #1111aa; }
a:active { color: #1111aa; }
a:visited { color: #111166; }
a.local:link { color: #11aa11; }
a.local:active { color: #11aa11; }
a.local:visited { color: #116611; }
a.intern:link { color: #1111aa; }
a.intern:active { color: #1111aa; }
a.intern:visited { color: #111166; }
a.extern:link { color: #aa1111; }
a.extern:active { color: #aa1111; }
a.extern:visited { color: #661111; }
a.quiet:link { color: black; }
a.quiet:active { color: black; }
a.quiet:visited { color: black; }
div.verbatim
{ font-family: monospace;
margin-top: 1em;
margin-bottom: 1em;
font-size: 10pt;
margin-left: 2em;
white-space: pre;
}
div.indent
{ margin-left: 8%;
margin-right: 0%;
}
.right { text-align: right; }
.left { text-align: left; }
.nowrap { white-space: nowrap; }
.item_leader
{ position: relative;
margin-left: 8%;
}
.item_compact { position: absolute; vertical-align: baseline; }
.item_cascade { position: relative; }
.item_leftalign { text-align: left; }
.item_rightalign
{ width: 2em;
text-align: right;
}
.item_compact .item_rightalign
{ position: absolute;
width: 52em;
right: -2em;
text-align: right;
}
.item_text
{ position: relative;
margin-left: 3em;
}
.smallcaps { font-size: smaller; text-transform: uppercase }
/* END aephea.base.css */
body { font-family: "Garamond", "Gill Sans", "Verdana", sans-serif; }
body
{ text-align: justify;
margin-left: 8%;
margin-right: 8%;
}
</style>
<title>uruk</title>
</head>
<body>
<p style="text-align:right">
9 авг 2013&nbsp;&nbsp;&nbsp;
<a class="local" href="uruk.ps"><b>uruk</b></a>
20130809
</p>
<div class=" itemize " style="margin-top:1em; font-size:100%">
<div class=" item_compact"><div class=" item_rightalign nowrap " style="right:-3em">1.</div></div>
<div class=" item_text " style="margin-left:4em">
<a class="intern" href="#name">NAME</a>
</div>
<div class=" item_compact"><div class=" item_rightalign nowrap " style="right:-3em">2.</div></div>
<div class=" item_text " style="margin-left:4em">
<a class="intern" href="#synopsis">SYNOPSIS</a>
</div>
<div class=" item_compact"><div class=" item_rightalign nowrap " style="right:-3em">3.</div></div>
<div class=" item_text " style="margin-left:4em">
<a class="intern" href="#description">DESCRIPTION</a>
</div>
<div class=" item_compact"><div class=" item_rightalign nowrap " style="right:-3em">4.</div></div>
<div class=" item_text " style="margin-left:4em">
<a class="intern" href="#quick setup guide">QUICK SETUP GUIDE</a>
</div>
<div class=" item_compact"><div class=" item_rightalign nowrap " style="right:-3em">5.</div></div>
<div class=" item_text " style="margin-left:4em">
<a class="intern" href="#getting started">GETTING STARTED</a>
</div>
<div class=" item_compact"><div class=" item_rightalign nowrap " style="right:-3em">6.</div></div>
<div class=" item_text " style="margin-left:4em">
<a class="intern" href="#loading a new rc file">LOADING A NEW <i>rc</i> FILE</a>
</div>
<div class=" item_compact"><div class=" item_rightalign nowrap " style="right:-3em">7.</div></div>
<div class=" item_text " style="margin-left:4em">
<a class="intern" href="#the gory details uruk internals">THE GORY DETAILS: uruk INTERNALS</a>
</div>
<div class=" item_compact"><div class=" item_rightalign nowrap " style="right:-3em">8.</div></div>
<div class=" item_text " style="margin-left:4em">
<a class="intern" href="#using uruk-save as the initscript backend">USING uruk-save AS THE INITSCRIPT BACKEND</a>
</div>
<div class=" item_compact"><div class=" item_rightalign nowrap " style="right:-3em">9.</div></div>
<div class=" item_text " style="margin-left:4em">
<a class="intern" href="#policy">DEFAULT POLICY</a>
</div>
<div class=" item_compact"><div class=" item_rightalign nowrap " style="right:-3em">10.</div></div>
<div class=" item_text " style="margin-left:4em">
<a class="intern" href="#warning">WARNING</a>
</div>
<div class=" item_compact"><div class=" item_rightalign nowrap " style="right:-3em">11.</div></div>
<div class=" item_text " style="margin-left:4em">
<a class="intern" href="#environment">ENVIRONMENT</a>
</div>
<div class=" item_compact"><div class=" item_rightalign nowrap " style="right:-3em">12.</div></div>
<div class=" item_text " style="margin-left:4em">
<a class="intern" href="#see also">SEE ALSO</a>
</div>
<div class=" item_compact"><div class=" item_rightalign nowrap " style="right:-3em">13.</div></div>
<div class=" item_text " style="margin-left:4em">
<a class="intern" href="#copyright">COPYRIGHT</a>
</div>
<div class=" item_compact"><div class=" item_rightalign nowrap " style="right:-3em">14.</div></div>
<div class=" item_text " style="margin-left:4em">
<a class="intern" href="#author">AUTHOR</a>
</div>
</div>

<a name="name"></a>
<h2>NAME</h2>
<p style="margin-bottom:0" class="asd_par">
uruk &mdash; wrapper for Linux iptables, for managing firewall rules</p>

<a name="synopsis"></a>
<h2>SYNOPSIS</h2>
<b>uruk</b>

<a name="description"></a>
<h2>DESCRIPTION</h2>
<b>uruk</b> loads an <i>rc</i> file (see <a class="local sibling" href="uruk-rc.html">uruk-rc(5)</a>) which defines
network service access policy, and invokes <b>iptables(8)</b> to set up firewall
rules implementing this policy. By default the file <tt>/etc/uruk/rc</tt> is used; one can
overrule this by specifying another file in the URUK_CONFIG environment
variable. Under some circumstances, it's useful to use another command for
iptables; this can be achieved by setting the URUK_IPTABLES (and/or
URUK_IP6TABLES) environment variables. See <a class="local sibling" href="uruk-rc.html">uruk-rc(5)</a> for
details.

<a name="quick setup guide"></a>
<h2>QUICK SETUP GUIDE</h2>
Uruk will <i>not</i> "just work" out of the box. It needs manual configuration.
For those of you who don't like reading lots of documentation:
<div class="verbatim"> # cp /usr/share/doc/uruk/examples/rc \
     /etc/uruk/rc
 # vi /etc/uruk/rc
 # urukctl start</div>

<a name="getting started"></a>
<h2>GETTING STARTED</h2>
Once the <b>uruk</b> script is installed, you want to go use it, of course. We'll
give a detailed description of what to do here.
<p style="margin-bottom:0" class="asd_par">
First, create an <i>rc</i> file. See <a class="local sibling" href="uruk-rc.html">uruk-rc(5)</a> for info on how to
do this. Once this file is created and installed (this script looks in
<tt>/etc/uruk/rc</tt> by default), you're ready to run <b>uruk</b>. You might want to test your
<i>rc</i> file by running <b>uruk</b> in debug mode, see <a class="local sibling" href="uruk-rc.html">uruk-rc(5)</a>.
There are at least 3 ways to load your <i>rc</i> file. We'll first describe a low
level one: using vanilla iptables.
</p>
<p style="margin-bottom:0"><b>Vanilla iptables</b><br>
After editing <i>rc</i>, load your rules like this. First flush your current rules:
<div class="verbatim"> # iptables -F
 # ip6tables -F</div>
Then enable your <i>rc</i> rules
<div class="verbatim"> # uruk</div>
. Inspect the rules by doing:
<div class="verbatim"> # iptables -L
 # ip6tables -L</div>
.
If you want to make these changes survive a reboot, use the init script as
shipped with this package. If you'd rather write your own init script, the
<b>iptables-restore(8)</b> and <b>iptables-save(8)</b> commands from the iptables
package might be helpful.
</p>
<p style="margin-bottom:0"><b>Using the Uruk init script</b><br>
Assumed is the Uruk init script is installed as explained in the README file.
Optionally, install <tt>/etc/default/uruk</tt> (or <tt>/etc/sysconfig/uruk</tt>) and
tweak it. An example file is in <tt>/usr/share/doc/uruk/examples/default</tt> (You might like to enable
support for <b>uruk-save</b>.) Now activate uruk by doing:
<div class="verbatim"> # urukctl start</div>
Now your pre-uruk iptables rules (if any) are saved as the "inactive" ruleset.
While executing <tt>urukctl start</tt>, your box is open during a short while.
If you don't like this, read below about <b>uruk-save</b>.
</p>
<p style="margin-bottom:0" class="asd_par">
When rebooting, everything will be fine: <tt>/etc/init.d/uruk</tt> stores
state in <tt>/var/lib/uruk/iptables</tt>, using
iptables-save(8), which comes with Linux iptables.
</p>
<p style="margin-bottom:0"><b>Using Debian ifupdown</b><br>
In case you have just one network interface which should get protected, you
could use <b>interfaces(5)</b> from the Debian ifupdown package instead of the
init script. Suppose you'd like to protect <tt>ppp0</tt>, and would like not to
interfere with traffic on eth0: your other network interface.
First write an <i>rc</i> file. Be sure it features
<div class="verbatim"> interfaces_unprotect="lo eth0"</div>
Then run:
<div class="verbatim"> # mkdir -p /var/lib/uruk/iptables

 # iptables -F

 # iptables-save -c &gt; /var/lib/uruk/iptables/down
 # uruk
 # iptables-save -c &gt; /var/lib/uruk/iptables/up</div>
Add
<div class="verbatim"> pre-up iptables-restore &lt; /var/lib/uruk/iptables/up
 post-down iptables-restore &lt; /var/lib/uruk/iptables/down</div>
to your interfaces stanza, in your <tt>/etc/network/interfaces</tt> .
</p>
<p style="margin-bottom:0" class="asd_par">
Similar tricks might be possible on GNU/Linux systems from other distributions.
The author is interested.
</p>

<a name="loading a new rc file"></a>
<h2>LOADING A NEW <i>rc</i> FILE</h2>
Need to change your rules?
<p style="margin-bottom:0"><b>Using the Uruk init script</b><br>
Do
<div class="verbatim"> # vi /etc/uruk/rc
 # urukctl force-reload</div>
While executing <tt>urukctl force-reload</tt>, your box is open during a short
while. If you don't like this, read below about <b>uruk-save</b>.
</p>

<a name="the gory details uruk internals"></a>
<h2>THE GORY DETAILS: uruk INTERNALS</h2>
The <b>uruk</b> script works like (and looks like) the list of statements below. Of
course, take a look at <tt>/sbin/uruk</tt> for the final word on the workings.
<div class=" itemize " style="margin-top:1em; font-size:100%">
<div class=" item_cascade"><div class=" item_leftalign " >1</div></div>
<div class=" item_text " style="margin-left:2em">
<i>rc</i> is sourced as a shell script
</div>
<div class=" item_cascade"><div class=" item_leftalign " >2</div></div>
<div class=" item_text " style="margin-left:2em">
Traffic on $interfaces_unprotect (just lo per default)
is trusted:
<div class="verbatim"> $iptables -A INPUT -i $iface -j ACCEPT</div>
</div>
<div class=" item_cascade"><div class=" item_leftalign " >3</div></div>
<div class=" item_text " style="margin-left:2em">
$rc_a is sourced as a shell script, or, in case $rc_a is a directory, all
files matching $rc_a/*.rc are sourced as shell scripts
</div>
<div class=" item_cascade"><div class=" item_leftalign " >4</div></div>
<div class=" item_text " style="margin-left:2em">
ESTABLISHED and RELATED packets are ACCEPT-ed:
<div class="verbatim"> $iptables -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED \
  -j ACCEPT</div>
</div>
<div class=" item_cascade"><div class=" item_leftalign " >5</div></div>
<div class=" item_text " style="margin-left:2em">
$rc_b is sourced
</div>
<div class=" item_cascade"><div class=" item_leftalign " >6</div></div>
<div class=" item_text " style="margin-left:2em">
$interfaces gets protected against spoofing: we don't allow anyone to
spoof non-routeable addresses. We block outgoing packets that don't have
our address as source: they are either spoofed or something is
misconfigured (NAT disabled, for instance). We want to be nice and don't
send out garbage.
<div class="verbatim"> $iptables -A INPUT -i $iface --source $no_route_ip \
  -j DROP</div>
We drop all incoming packets which don't have us as destination:
<div class="verbatim"> $iptables -A OUTPUT -o $iface --source ! "$ip" \
  -j DROP</div>
And we always allow outgoing connections:
<div class="verbatim"> $iptables -A OUTPUT -m conntrack --ctstate NEW -o $iface \
  -j ACCEPT</div>
</div>
<div class=" item_cascade"><div class=" item_leftalign " >7</div></div>
<div class=" item_text " style="margin-left:2em">
$rc_c is sourced
</div>
<div class=" item_cascade"><div class=" item_leftalign " >8</div></div>
<div class=" item_text " style="margin-left:2em">
Allow traffic to offered services, from trusted sources:
<div class="verbatim"> $iptables -A INPUT -m conntrack --ctstate NEW \
  -i $iface --protocol $proto --source "$source" \
  --destination "$ip" --destination-port "$port" \
  -j ACCEPT</div>
</div>
<div class=" item_cascade"><div class=" item_leftalign " >9</div></div>
<div class=" item_text " style="margin-left:2em">
$rc_d is sourced
</div>
<div class=" item_cascade"><div class=" item_leftalign " >10</div></div>
<div class=" item_text " style="margin-left:2em">
Don't answer broadcast and multicast packets:
<div class="verbatim"> $iptables -A INPUT -i $iface --destination "$bcast" \
  -j DROP</div>
</div>
<div class=" item_cascade"><div class=" item_leftalign " >11</div></div>
<div class=" item_text " style="margin-left:2em">
$rc_f is sourced
</div>
<div class=" item_cascade"><div class=" item_leftalign " >12</div></div>
<div class=" item_text " style="margin-left:2em">
Explicitly allow a subset of the ICMP types. (We disallow all other
traffic later.)
<div class="verbatim"> $iptables -A INPUT --protocol icmp --icmp-type $type \
  -j ACCEPT</div>
</div>
<div class=" item_cascade"><div class=" item_leftalign " >13</div></div>
<div class=" item_text " style="margin-left:2em">
$rc_g is sourced
</div>
<div class=" item_cascade"><div class=" item_leftalign " >14</div></div>
<div class=" item_text " style="margin-left:2em">
Log packets (which make it till here)
<div class="verbatim"> $iptables -A INPUT -j LOG --log-level debug \
  --log-prefix 'iptables: '</div>
</div>
<div class=" item_cascade"><div class=" item_leftalign " >15</div></div>
<div class=" item_text " style="margin-left:2em">
$rc_h is sourced
</div>
<div class=" item_cascade"><div class=" item_leftalign " >16</div></div>
<div class=" item_text " style="margin-left:2em">
Reject all other packets
<div class="verbatim"> $iptables -A INPUT -j REJECT</div>
</div>
<div class=" item_cascade"><div class=" item_leftalign " >17</div></div>
<div class=" item_text " style="margin-left:2em">
$rc_i is sourced
</div>
</div>

<a name="using uruk-save as the initscript backend"></a>
<h2>USING uruk-save AS THE INITSCRIPT BACKEND</h2>
By default, <b>uruk-save</b> is not used by the uruk init script. You might want to
use it, though. The <b>uruk-save</b> script is faster and when using <b>uruk-save</b>,
your box won't be open while loading new rules. But beware: <b>uruk-save</b> is not
as robust as using <b>uruk</b> itself.
<p style="margin-bottom:0" class="asd_par">
The script <b>urukctl</b> (and thus the uruk init script) will use <b>uruk-save</b> only if
asked to do so in <tt>/etc/default/uruk</tt> (or <tt>/etc/sysconfig/uruk</tt>). If
this file features
<div class="verbatim">
 enable_uruk_save=true</div>
<b>uruk-save</b> is used whenever appropriate.
See <a class="local sibling" href="uruk-save.html">uruk-save(8)</a> for more details.
</p>

<a name="policy"></a>
<h2>DEFAULT POLICY</h2>
By default, <b>uruk</b> drops packets which have unknown RFC 1918 private network
addresses in their source or destination.
<p style="margin-bottom:0" class="asd_par">
It rejects packets with source nor destination for one of our IPs.
</p> <p style="margin-bottom:0" class="asd_par">
Packets belonging to locally initiated sessions are allowed: we match state;
the local host can act as a client for any remote service.
</p> <p style="margin-bottom:0" class="asd_par">
By default, <b>uruk</b> drops all ICMP packets (except those for interfaces in
$interfaces_unprotect) with type other than
<div class=" itemize " style="margin-top:1em; font-size:100%">
<div class=" item_cascade"><div class=" item_leftalign " ><span class="itembullet">&bull;</span></div></div>
<div class=" item_text " style="margin-left:2em">
address-mask-reply
</div>
<div class=" item_cascade"><div class=" item_leftalign " ><span class="itembullet">&bull;</span></div></div>
<div class=" item_text " style="margin-left:2em">
address-mask-request
</div>
<div class=" item_cascade"><div class=" item_leftalign " ><span class="itembullet">&bull;</span></div></div>
<div class=" item_text " style="margin-left:2em">
destination-unreachable (this is a catch-all for a lot of types)
</div>
<div class=" item_cascade"><div class=" item_leftalign " ><span class="itembullet">&bull;</span></div></div>
<div class=" item_text " style="margin-left:2em">
echo-request
</div>
<div class=" item_cascade"><div class=" item_leftalign " ><span class="itembullet">&bull;</span></div></div>
<div class=" item_text " style="margin-left:2em">
echo-reply
</div>
<div class=" item_cascade"><div class=" item_leftalign " ><span class="itembullet">&bull;</span></div></div>
<div class=" item_text " style="margin-left:2em">
parameter-problem (catch-all for ip-header-bad and required-option-missing)
</div>
<div class=" item_cascade"><div class=" item_leftalign " ><span class="itembullet">&bull;</span></div></div>
<div class=" item_text " style="margin-left:2em">
timestamp-reply
</div>
<div class=" item_cascade"><div class=" item_leftalign " ><span class="itembullet">&bull;</span></div></div>
<div class=" item_text " style="margin-left:2em">
timestamp-request
</div>
<div class=" item_cascade"><div class=" item_leftalign " ><span class="itembullet">&bull;</span></div></div>
<div class=" item_text " style="margin-left:2em">
ttl-zero-during-transit
</div>
<div class=" item_cascade"><div class=" item_leftalign " ><span class="itembullet">&bull;</span></div></div>
<div class=" item_text " style="margin-left:2em">
ttl-zero-during-reassembly
</div>
</div>
</p> <p style="margin-bottom:0" class="asd_par">
By default, the FORWARD chain is left untouched, so has policy ACCEPT. (This
won't do much harm, since packet forwarding is disabled by default in the Linux
kernel. However, if you don't mind being paranoid, you might want to add a
<div class="verbatim"> iptables --policy FORWARD REJECT</div>
to your $rc_a uruk hook. See <a class="local sibling" href="uruk-rc.html">uruk-rc(5)</a>.)
</p> <p style="margin-bottom:0" class="asd_par">
By default, <b>uruk</b> logs all UDP and TCP packets which are blocked by the user
defined policies. Loglevel is debug, logprefix is "iptables:". See
also the notes on <i>loglevel</i> in <a class="local sibling" href="uruk-rc.html">uruk-rc(5)</a>.
</p> <p style="margin-bottom:0" class="asd_par">
Blocked TCP packets are answered with a tcp-reset.
</p>

<a name="warning"></a>
<h2>WARNING</h2>
In order to keep the <b>uruk</b> script small and simple, the script does very little
error handling. It does not check the contents of the <i>rc</i> file in any way
before executing it. When your <i>rc</i> file contains bogus stuff, <b>uruk</b> will very
likely behave in unexpected ways. Caveat emptor.

<a name="environment"></a>
<h2>ENVIRONMENT</h2>
You can override some defaults in the shell before executing the uruk script.
<b>uruk</b> honors the following variables:
<div class=" itemize " style="margin-top:1em; font-size:100%">
<div class=" item_cascade"><div class=" item_leftalign " ><span class="itembullet">&bull;</span></div></div>
<div class=" item_text " style="margin-left:2em">
"URUK_CONFIG" Full pathname of <i>rc</i> file; <tt>/etc/uruk/rc</tt> by default.
</div>
<div class=" item_cascade"><div class=" item_leftalign " ><span class="itembullet">&bull;</span></div></div>
<div class=" item_text " style="margin-left:2em">
"URUK_IPTABLES" Full pathname of iptables executable.
<tt>/sbin/iptables</tt> by default. Overrides <i>iptables</i>.
</div>
<div class=" item_cascade"><div class=" item_leftalign " ><span class="itembullet">&bull;</span></div></div>
<div class=" item_text " style="margin-left:2em">
"URUK_IP6TABLES" Full pathname of ip6tables executable, for
IPv6 support. Overrides <i>ip6tables</i>.
</div>
<div class=" item_cascade"><div class=" item_leftalign " ><span class="itembullet">&bull;</span></div></div>
<div class=" item_text " style="margin-left:2em">
"URUK_INTERFACES_UNPROTECT" Default list of unprotected interfaces.
Overrides <i>interfaces_unprotect</i>. The default default is <tt>lo</tt>.
</div>
</div>

<a name="see also"></a>
<h2>SEE ALSO</h2>
<a class="local sibling" href="uruk-rc.html">uruk-rc(5)</a>, <a class="local sibling" href="uruk-save.html">uruk-save(8)</a>. The Uruk homepage is at
<a class="extern" href="http://mdcc.cx/uruk/">http://mdcc.cx/uruk/</a> .
<p style="margin-bottom:0" class="asd_par">
<b>iptables(8)</b>, <b>iptables-save(8)</b>,
<b>iptables-restore(8)</b>,
<b>ip6tables(8)</b>, <b>ip6tables-save(8)</b>,
<b>ip6tables-restore(8)</b>, <a class="extern" href="http://www.netfilter.org/">http://www.netfilter.org/</a>
</p> <p style="margin-bottom:0" class="asd_par">
<b>interfaces(5)</b>, <a class="extern" href="http://packages.debian.org/ifupdown">http://packages.debian.org/ifupdown</a>.
</p>

<a name="copyright"></a>
<h2>COPYRIGHT</h2>
Copyright (C) 2003 Stichting LogReport Foundation logreport@logreport.org;
Copyright (C) 2003, 2004 Tilburg University http://www.uvt.nl/;
Copyright (C) 2003-2013 Joost van Baal-Ilić &lt;joostvb-uruk@mdcc.cx&gt;
<p style="margin-bottom:0" class="asd_par">
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
</p> <p style="margin-bottom:0" class="asd_par">
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
</p> <p style="margin-bottom:0" class="asd_par">
You should have received a copy of the GNU General Public License along
with this program. If not, see <a class="extern" href="http://www.gnu.org/licenses/">http://www.gnu.org/licenses/</a>.
</p>

<a name="author"></a>
<h2>AUTHOR</h2>
Joost van Baal-Ilić &lt;joostvb-uruk@mdcc.cx&gt;
</body>
</html>