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1 <?xml version="1.0" encoding="utf-8"?>
2 <rss version='2.0' xmlns:lj='http://www.livejournal.org/rss/lj/1.0/' xmlns:atom="http://www.w3.org/2005/Atom">
3 <channel>
4 <title>Petter Reinholdtsen</title>
5 <description></description>
6 <link>http://people.skolelinux.org/pere/blog/</link>
7 <atom:link href="http://people.skolelinux.org/pere/blog/index.rss" rel="self" type="application/rss+xml" />
8
9 <item>
10 <title>Public Trusted Timestamping services for everyone</title>
11 <link>http://people.skolelinux.org/pere/blog/Public_Trusted_Timestamping_services_for_everyone.html</link>
12 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Public_Trusted_Timestamping_services_for_everyone.html</guid>
13 <pubDate>Tue, 25 Mar 2014 12:50:00 +0100</pubDate>
14 <description>&lt;p&gt;Did you ever need to store logs or other files in a way that would
15 allow it to be used as evidence in court, and needed a way to
16 demonstrate without reasonable doubt that the file had not been
17 changed since it was created? Or, did you ever need to document that
18 a given document was received at some point in time, like some
19 archived document or the answer to an exam, and not changed after it
20 was received? The problem in these settings is to remove the need to
21 trust yourself and your computers, while still being able to prove
22 that a file is the same as it was at some given time in the past.&lt;/p&gt;
23
24 &lt;p&gt;A solution to these problems is to have a trusted third party
25 &quot;stamp&quot; the document and verify that at some given time the document
26 looked a given way. Such
27 &lt;a href=&quot;https://en.wikipedia.org/wiki/Notarius&quot;&gt;notarius&lt;/a&gt; service
28 have been around for thousands of years, and its digital equivalent is
29 called a
30 &lt;a href=&quot;http://en.wikipedia.org/wiki/Trusted_timestamping&quot;&gt;trusted
31 timestamping service&lt;/a&gt;. &lt;a href=&quot;http://www.ietf.org/&quot;&gt;The Internet
32 Engineering Task Force&lt;/a&gt; standardised how such service could work a
33 few years ago as &lt;a href=&quot;http://tools.ietf.org/html/rfc3161&quot;&gt;RFC
34 3161&lt;/a&gt;. The mechanism is simple. Create a hash of the file in
35 question, send it to a trusted third party which add a time stamp to
36 the hash and sign the result with its private key, and send back the
37 signed hash + timestamp. Anyone with the document and the signature
38 can then verify that the document matches the signature by creating
39 their own hash and checking the signature using the trusted third
40 party public key. There are several commercial services around
41 providing such timestamping. A quick search for
42 &quot;&lt;a href=&quot;https://duckduckgo.com/?q=rfc+3161+service&quot;&gt;rfc 3161
43 service&lt;/a&gt;&quot; pointed me to at least
44 &lt;a href=&quot;https://www.digistamp.com/technical/how-a-digital-time-stamp-works/&quot;&gt;DigiStamp&lt;/a&gt;,
45 &lt;a href=&quot;http://www.quovadisglobal.co.uk/CertificateServices/SigningServices/TimeStamp.aspx&quot;&gt;Quo
46 Vadis&lt;/a&gt;,
47 &lt;a href=&quot;https://www.globalsign.com/timestamp-service/&quot;&gt;Global Sign&lt;/a&gt;
48 and &lt;a href=&quot;http://www.globaltrustfinder.com/TSADefault.aspx&quot;&gt;Global
49 Trust Finder&lt;/a&gt;. The system work as long as the private key of the
50 trusted third party is not compromised.&lt;/p&gt;
51
52 &lt;p&gt;But as far as I can tell, there are very few public trusted
53 timestamp services available for everyone. I&#39;ve been looking for one
54 for a while now. But yesterday I found one over at
55 &lt;a href=&quot;https://www.pki.dfn.de/zeitstempeldienst/&quot;&gt;Deutches
56 Forschungsnetz&lt;/a&gt;mentioned in
57 &lt;a href=&quot;http://www.d-mueller.de/blog/dealing-with-trusted-timestamps-in-php-rfc-3161/&quot;&gt;a
58 blog by David Müller&lt;/a&gt;. I then found a good recipe on how to use
59 over at the
60 &lt;a href=&quot;http://www.rz.uni-greifswald.de/support/dfn-pki-zertifikate/zeitstempeldienst.html&quot;&gt;University
61 of Greifswald&lt;/a&gt;. The OpenSSL library contain both server and tools
62 to use and set up your own signing service. See the ts(1SSL),
63 tsget(1SSL) manual pages for more details. The following shell script
64 demonstrate how to extract a signed timestamp for any file on the disk
65 in a Debian environment:
66
67 &lt;p&gt;&lt;blockquote&gt;&lt;pre&gt;
68 #!/bin/sh
69 set -e
70 url=&quot;http://zeitstempel.dfn.de&quot;
71 caurl=&quot;https://pki.pca.dfn.de/global-services-ca/pub/cacert/chain.txt&quot;
72 reqfile=$(mktemp -t tmp.XXXXXXXXXX.tsq)
73 resfile=$(mktemp -t tmp.XXXXXXXXXX.tsr)
74 cafile=chain.txt
75 if [ ! -f $cafile ] ; then
76 wget -O $cafile &quot;$caurl&quot;
77 fi
78 openssl ts -query -data &quot;$1&quot; -cert | tee &quot;$reqfile&quot; \
79 | /usr/lib/ssl/misc/tsget -h &quot;$url&quot; -o &quot;$resfile&quot;
80 openssl ts -reply -in &quot;$resfile&quot; -text 1&gt;&amp;2
81 openssl ts -verify -data &quot;$1&quot; -in &quot;$resfile&quot; -CAfile &quot;$cafile&quot; 1&gt;&amp;2
82 base64 &lt; &quot;$resfile&quot;
83 rm &quot;$reqfile&quot; &quot;$resfile&quot;
84 &lt;/pre&gt;&lt;/blockquote&gt;&lt;/p&gt;
85
86 &lt;p&gt;The argument to the script is the file to timestamp, and the output
87 is a base64 encoded version of the signature to STDOUT and details
88 about the signature to STDERR. Note that due to
89 &lt;a href=&quot;http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=742553&quot;&gt;a bug
90 in the tsget script&lt;/a&gt;, you might need to modify the included script
91 and remove the last line. Or just write your own HTTP uploader using
92 curl. :) Now you too can prove and verify that files have not been
93 changed.&lt;/p&gt;
94
95 &lt;p&gt;But the Internet need more public trusted timestamp services.
96 Perhaps something for &lt;a href=&quot;http://www.uninett.no/&quot;&gt;Uninett&lt;/a&gt; or
97 my work place the &lt;a href=&quot;http://www.uio.no/&quot;&gt;University of Oslo&lt;/a&gt;
98 to set up?&lt;/p&gt;
99 </description>
100 </item>
101
102 <item>
103 <title>Video DVD reader library / python-dvdvideo - nice free software</title>
104 <link>http://people.skolelinux.org/pere/blog/Video_DVD_reader_library___python_dvdvideo___nice_free_software.html</link>
105 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Video_DVD_reader_library___python_dvdvideo___nice_free_software.html</guid>
106 <pubDate>Fri, 21 Mar 2014 15:25:00 +0100</pubDate>
107 <description>&lt;p&gt;Keeping your DVD collection safe from scratches and curious
108 children fingers while still having it available when you want to see a
109 movie is not straight forward. My preferred method at the moment is
110 to store a full copy of the ISO on a hard drive, and use VLC, Popcorn
111 Hour or other useful players to view the resulting file. This way the
112 subtitles and bonus material are still available and using the ISO is
113 just like inserting the original DVD record in the DVD player.&lt;/p&gt;
114
115 &lt;p&gt;Earlier I used dd for taking security copies, but it do not handle
116 DVDs giving read errors (which are quite a few of them). I&#39;ve also
117 tried using
118 &lt;a href=&quot;http://people.skolelinux.org/pere/blog/Ripping_problematic_DVDs_using_dvdbackup_and_genisoimage.html&quot;&gt;dvdbackup
119 and genisoimage&lt;/a&gt;, but these days I use the marvellous python library
120 and program
121 &lt;a href=&quot;http://bblank.thinkmo.de/blog/new-software-python-dvdvideo&quot;&gt;python-dvdvideo&lt;/a&gt;
122 written by Bastian Blank. It is
123 &lt;a href=&quot;http://packages.qa.debian.org/p/python-dvdvideo.html&quot;&gt;in Debian
124 already&lt;/a&gt; and the binary package name is python3-dvdvideo. Instead
125 of trying to read every block from the DVD, it parses the file
126 structure and figure out which block on the DVD is actually in used,
127 and only read those blocks from the DVD. This work surprisingly well,
128 and I have been able to almost backup my entire DVD collection using
129 this method.&lt;/p&gt; So far, python-dvdvideo have failed on between 10 and
130 20 DVDs, which is a small fraction of my collection. The most common
131 problem is
132 &lt;a href=&quot;https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=720831&quot;&gt;DVDs
133 using UTF-16 instead of UTF-8 characters&lt;/a&gt;, which according to
134 Bastian is against the DVD specification (and seem to cause some
135 players to fail too). A rarer problem is what seem to be inconsistent
136 DVD structures, as the python library
137 &lt;a href=&quot;https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=723079&quot;&gt;claim
138 there is a overlap between objects&lt;/a&gt;. An equally rare problem claim
139 &lt;a href=&quot;https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=741878&quot;&gt;some
140 value is out of range&lt;/a&gt;. No idea what is going on there. I wish I
141 knew enough about the DVD format to fix these, to ensure my movie
142 collection will stay with me in the future.&lt;/p&gt;
143
144 &lt;p&gt;So, if you need to keep your DVDs safe, back them up using
145 python-dvdvideo. :)&lt;/p&gt;
146 </description>
147 </item>
148
149 <item>
150 <title>Norsk utgave av Alaveteli / WhatDoTheyKnow på trappene</title>
151 <link>http://people.skolelinux.org/pere/blog/Norsk_utgave_av_Alaveteli___WhatDoTheyKnow_p__trappene.html</link>
152 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Norsk_utgave_av_Alaveteli___WhatDoTheyKnow_p__trappene.html</guid>
153 <pubDate>Sun, 16 Mar 2014 09:30:00 +0100</pubDate>
154 <description>&lt;p&gt;Det offentlige Norge har mye kunnskap og informasjon. Men hvordan
155 kan en få tilgang til den på en enkel måte? Takket være et lite
156 knippe lover og tilhørende forskrifter, blant annet
157 &lt;a href=&quot;http://lovdata.no/dokument/NL/lov/2006-05-19-16&quot;&gt;offentlighetsloven&lt;/a&gt;,
158 &lt;a href=&quot;http://lovdata.no/dokument/NL/lov/2003-05-09-31&quot;&gt;miljøinformasjonsloven&lt;/a&gt;
159 og
160 &lt;a href=&quot;http://lovdata.no/dokument/NL/lov/1967-02-10/&quot;&gt;forvaltningsloven&lt;/a&gt;
161 har en rett til å spørre det offentlige og få svar. Men det finnes
162 intet offentlig arkiv over hva andre har spurt om, og dermed risikerer en
163 å måtte forstyrre myndighetene gang på gang for å få tak i samme
164 informasjonen på nytt. &lt;a href=&quot;http://www.mysociety.org/&quot;&gt;Britiske
165 mySociety&lt;/a&gt; har laget tjenesten
166 &lt;a href=&quot;http://www.whatdotheyknow.com/&quot;&gt;WhatDoTheyKnow&lt;/a&gt; som gjør
167 noe med dette. I Storbritannia blir WhatdoTheyKnow brukt i
168 &lt;a href=&quot;http://www.mysociety.org/2011/07/01/whatdotheyknows-share-of-central-government-foi-requests-q2-2011/&quot;&gt;ca
169 15% av alle innsynsforespørsler mot sentraladministrasjonen&lt;/a&gt;.
170 Prosjektet heter &lt;a href=&quot;http://www.alaveteli.org/&quot;&gt;Alaveteli&lt;/A&gt;, og
171 er takk i bruk en rekke steder etter at løsningen ble generalisert og
172 gjort mulig å oversette. Den hjelper borgerne med å be om innsyn,
173 rådgir ved purringer og klager og lar alle se hvilke henvendelser som
174 er sendt til det offentlige og hvilke svar som er kommet inn, i et
175 søkpart arkiv. Her i Norge holder vi i foreningen NUUG på å få opp en
176 norsk utgave av Alaveteli, og her trenger vi din hjelp med
177 oversettelsen.&lt;/p&gt;
178
179 &lt;p&gt;Så langt er 76 % av Alaveteli oversatt til norsk bokmål, men vi
180 skulle gjerne vært oppe i 100 % før lansering. Oversettelsen gjøres
181&lt;a href=&quot;https://www.transifex.com/projects/p/alaveteli/&quot;&gt;Transifex,
182 der enhver som registrerer seg&lt;/a&gt; og ber om tilgang til
183 bokmålsoversettelsen får bidra. Vi har satt opp en test av tjenesten
184 (som ikke sender epost til det offentlige, kun til oss som holder på å
185 sette opp tjenesten) på maskinen
186 &lt;a href=&quot;http://alaveteli-dev.nuug.no/&quot;&gt;alaveteli-dev.nuug.no&lt;/a&gt;, der
187 en kan se hvordan de oversatte meldingen blir seende ut på nettsiden.
188 Når tjenesten lanseres vil den hete
189 &lt;a href=&quot;https://www.mimesbrønn.no/&quot;&gt;Mimes brønn&lt;/a&gt;, etter
190 visdomskilden som Odin måtte gi øyet sitt for å få drikke i. Den
191 nettsiden er er ennå ikke klar til bruk.&lt;/p&gt;
192
193 &lt;p&gt;Hvis noen vil oversette til nynorsk også, så skal vi finne ut
194 hvordan vi lager en flerspråklig tjeneste. Men i første omgang er
195 fokus på bokmålsoversettelsen, der vi selv har nok peiling til å ha
196 fått oversatt 76%, men trenger hjelp for å komme helt i mål. :)&lt;/p&gt;
197 </description>
198 </item>
199
200 <item>
201 <title>Freedombox on Dreamplug, Raspberry Pi and virtual x86 machine</title>
202 <link>http://people.skolelinux.org/pere/blog/Freedombox_on_Dreamplug__Raspberry_Pi_and_virtual_x86_machine.html</link>
203 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Freedombox_on_Dreamplug__Raspberry_Pi_and_virtual_x86_machine.html</guid>
204 <pubDate>Fri, 14 Mar 2014 11:00:00 +0100</pubDate>
205 <description>&lt;p&gt;The &lt;a href=&quot;https://wiki.debian.org/FreedomBox&quot;&gt;Freedombox
206 project&lt;/a&gt; is working on providing the software and hardware for
207 making it easy for non-technical people to host their data and
208 communication at home, and being able to communicate with their
209 friends and family encrypted and away from prying eyes. It has been
210 going on for a while, and is slowly progressing towards a new test
211 release (0.2).&lt;/p&gt;
212
213 &lt;p&gt;And what day could be better than the Pi day to announce that the
214 new version will provide &quot;hard drive&quot; / SD card / USB stick images for
215 Dreamplug, Raspberry Pi and VirtualBox (or any other virtualization
216 system), and can also be installed using a Debian installer preseed
217 file. The Debian based Freedombox is now based on Debian Jessie,
218 where most of the needed packages used are already present. Only one,
219 the freedombox-setup package, is missing. To try to build your own
220 boot image to test the current status, fetch the freedom-maker scripts
221 and build using
222 &lt;a href=&quot;http://packages.qa.debian.org/vmdebootstrap&quot;&gt;vmdebootstrap&lt;/a&gt;
223 with a user with sudo access to become root:
224
225 &lt;pre&gt;
226 git clone http://anonscm.debian.org/git/freedombox/freedom-maker.git \
227 freedom-maker
228 sudo apt-get install git vmdebootstrap mercurial python-docutils \
229 mktorrent extlinux virtualbox qemu-user-static binfmt-support \
230 u-boot-tools
231 make -C freedom-maker dreamplug-image raspberry-image virtualbox-image
232 &lt;/pre&gt;
233
234 &lt;p&gt;Root access is needed to run debootstrap and mount loopback
235 devices. See the README for more details on the build. If you do not
236 want all three images, trim the make line. But note that thanks to &lt;a
237 href=&quot;https://bugs.debian.org/741407&quot;&gt;a race condition in
238 vmdebootstrap&lt;/a&gt;, the build might fail without the patch to the
239 kpartx call.&lt;/p&gt;
240
241 &lt;p&gt;If you instead want to install using a Debian CD and the preseed
242 method, boot a Debian Wheezy ISO and use this boot argument to load
243 the preseed values:&lt;/p&gt;
244
245 &lt;pre&gt;
246 url=&lt;a href=&quot;http://www.reinholdtsen.name/freedombox/preseed-jessie.dat&quot;&gt;http://www.reinholdtsen.name/freedombox/preseed-jessie.dat&lt;/a&gt;
247 &lt;/pre&gt;
248
249 &lt;p&gt;But note that due to &lt;a href=&quot;https://bugs.debian.org/740673&quot;&gt;a
250 recently introduced bug in apt in Jessie&lt;/a&gt;, the installer will
251 currently hang while setting up APT sources. Killing the
252 &#39;&lt;tt&gt;apt-cdrom ident&lt;/tt&gt;&#39; process when it hang a few times during the
253 installation will get the installation going. This affect all
254 installations in Jessie, and I expect it will be fixed soon.&lt;/p&gt;
255
256 Give it a go and let us know how it goes on the mailing list, and help
257 us get the new release published. :) Please join us on
258 &lt;a href=&quot;irc://irc.debian.org:6667/%23freedombox&quot;&gt;IRC (#freedombox on
259 irc.debian.org)&lt;/a&gt; and
260 &lt;a href=&quot;http://lists.alioth.debian.org/mailman/listinfo/freedombox-discuss&quot;&gt;the
261 mailing list&lt;/a&gt; if you want to help make this vision come true.&lt;/p&gt;
262 </description>
263 </item>
264
265 <item>
266 <title>How to add extra storage servers in Debian Edu / Skolelinux</title>
267 <link>http://people.skolelinux.org/pere/blog/How_to_add_extra_storage_servers_in_Debian_Edu___Skolelinux.html</link>
268 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/How_to_add_extra_storage_servers_in_Debian_Edu___Skolelinux.html</guid>
269 <pubDate>Wed, 12 Mar 2014 12:50:00 +0100</pubDate>
270 <description>&lt;p&gt;On larger sites, it is useful to use a dedicated storage server for
271 storing user home directories and data. The design for handling this
272 in &lt;a href=&quot;http://www.skolelinux.org/&quot;&gt;Debian Edu / Skolelinux&lt;/a&gt;, is
273 to update the automount rules in LDAP and let the automount daemon on
274 the clients take care of the rest. I was reminded about the need to
275 document this better when one of the customers of
276 &lt;a href=&quot;http://www.slxdrift.no/&quot;&gt;Skolelinux Drift AS&lt;/a&gt;, where I am
277 on the board of directors, asked about how to do this. The steps to
278 get this working are the following:&lt;/p&gt;
279
280 &lt;p&gt;&lt;ol&gt;
281
282 &lt;li&gt;Add new storage server in DNS. I use nas-server.intern as the
283 example host here.&lt;/li&gt;
284
285 &lt;li&gt;Add automoun LDAP information about this server in LDAP, to allow
286 all clients to automatically mount it on reqeust.&lt;/li&gt;
287
288 &lt;li&gt;Add the relevant entries in tjener.intern:/etc/fstab, because
289 tjener.intern do not use automount to avoid mounting loops.&lt;/li&gt;
290
291 &lt;/ol&gt;&lt;/p&gt;
292
293 &lt;p&gt;DNS entries are added in GOsa², and not described here. Follow the
294 &lt;a href=&quot;https://wiki.debian.org/DebianEdu/Documentation/Wheezy/GettingStarted&quot;&gt;instructions
295 in the manual&lt;/a&gt; (Machine Management with GOsa² in section Getting
296 started).&lt;/p&gt;
297
298 &lt;p&gt;Ensure that the NFS export points on the server are exported to the
299 relevant subnets or machines:&lt;/p&gt;
300
301 &lt;p&gt;&lt;blockquote&gt;&lt;pre&gt;
302 root@tjener:~# showmount -e nas-server
303 Export list for nas-server:
304 /storage 10.0.0.0/8
305 root@tjener:~#
306 &lt;/pre&gt;&lt;/blockquote&gt;&lt;/p&gt;
307
308 &lt;p&gt;Here everything on the backbone network is granted access to the
309 /storage export. With NFSv3 it is slightly better to limit it to
310 netgroup membership or single IP addresses to have some limits on the
311 NFS access.&lt;/p&gt;
312
313 &lt;p&gt;The next step is to update LDAP. This can not be done using GOsa²,
314 because it lack a module for automount. Instead, use ldapvi and add
315 the required LDAP objects using an editor.&lt;/p&gt;
316
317 &lt;p&gt;&lt;blockquote&gt;&lt;pre&gt;
318 ldapvi --ldap-conf -ZD &#39;(cn=admin)&#39; -b ou=automount,dc=skole,dc=skolelinux,dc=no
319 &lt;/pre&gt;&lt;/blockquote&gt;&lt;/p&gt;
320
321 &lt;p&gt;When the editor show up, add the following LDAP objects at the
322 bottom of the document. The &quot;/&amp;&quot; part in the last LDAP object is a
323 wild card matching everything the nas-server exports, removing the
324 need to list individual mount points in LDAP.&lt;/p&gt;
325
326 &lt;p&gt;&lt;blockquote&gt;&lt;pre&gt;
327 add cn=nas-server,ou=auto.skole,ou=automount,dc=skole,dc=skolelinux,dc=no
328 objectClass: automount
329 cn: nas-server
330 automountInformation: -fstype=autofs --timeout=60 ldap:ou=auto.nas-server,ou=automount,dc=skole,dc=skolelinux,dc=no
331
332 add ou=auto.nas-server,ou=automount,dc=skole,dc=skolelinux,dc=no
333 objectClass: top
334 objectClass: automountMap
335 ou: auto.nas-server
336
337 add cn=/,ou=auto.nas-server,ou=automount,dc=skole,dc=skolelinux,dc=no
338 objectClass: automount
339 cn: /
340 automountInformation: -fstype=nfs,tcp,rsize=32768,wsize=32768,rw,intr,hard,nodev,nosuid,noatime nas-server.intern:/&amp;
341 &lt;/pre&gt;&lt;/blockquote&gt;&lt;/p&gt;
342
343 &lt;p&gt;The last step to remember is to mount the relevant mount points in
344 tjener.intern by adding them to /etc/fstab, creating the mount
345 directories using mkdir and running &quot;mount -a&quot; to mount them.&lt;/p&gt;
346
347 &lt;p&gt;When this is done, your users should be able to access the files on
348 the storage server directly by just visiting the
349 /tjener/nas-server/storage/ directory using any application on any
350 workstation, LTSP client or LTSP server.&lt;/p&gt;
351 </description>
352 </item>
353
354 <item>
355 <title>Hvordan bør RFC 822-formattert epost lagres i en NOARK5-database?</title>
356 <link>http://people.skolelinux.org/pere/blog/Hvordan_b_r_RFC_822_formattert_epost_lagres_i_en_NOARK5_database_.html</link>
357 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Hvordan_b_r_RFC_822_formattert_epost_lagres_i_en_NOARK5_database_.html</guid>
358 <pubDate>Fri, 7 Mar 2014 15:20:00 +0100</pubDate>
359 <description>&lt;p&gt;For noen uker siden ble NXCs fri programvarelisenserte
360 NOARK5-løsning
361 &lt;a href=&quot;http://www.nuug.no/aktiviteter/20140211-noark/&quot;&gt;presentert hos
362 NUUG&lt;/a&gt; (video
363 &lt;a href=&quot;https://www.youtube.com/watch?v=JCb_dNS3MHQ&quot;&gt;på youtube
364 foreløbig&lt;/a&gt;), og det fikk meg til å titte litt mer på NOARK5,
365 standarden for arkivhåndtering i det offentlige Norge. Jeg lurer på
366 om denne kjernen kan være nyttig i et par av mine prosjekter, og for ett
367 av dem er det mest aktuelt å lagre epost. Jeg klarte ikke finne noen
368 anbefaling om hvordan RFC 822-formattert epost (aka Internett-epost)
369 burde lagres i NOARK5, selv om jeg vet at noen arkiver tar
370 PDF-utskrift av eposten med sitt epostprogram og så arkiverer PDF-en
371 (eller enda værre, tar papirutskrift og lagrer bildet av eposten som
372 PDF i arkivet).&lt;/p&gt;
373
374 &lt;p&gt;Det er ikke så mange formater som er akseptert av riksarkivet til
375 langtidsoppbevaring av offentlige arkiver, og PDF og XML er de mest
376 aktuelle i så måte. Det slo meg at det måtte da finnes en eller annen
377 egnet XML-representasjon og at det kanskje var enighet om hvilken som
378 burde brukes, så jeg tok mot til meg og spurte
379 &lt;a href=&quot;http://samdok.com/&quot;&gt;SAMDOK&lt;/a&gt;, en gruppe tilknyttet
380 arkivverket som ser ut til å jobbe med NOARK-samhandling, om de hadde
381 noen anbefalinger:
382
383 &lt;p&gt;&lt;blockquote&gt;
384 &lt;p&gt;Hei.&lt;/p&gt;
385
386 &lt;p&gt;Usikker på om dette er riktig forum å ta opp mitt spørsmål, men jeg
387 lurer på om det er definert en anbefaling om hvordan RFC
388 822-formatterte epost (aka vanlig Internet-epost) bør lages håndteres
389 i NOARK5, slik at en bevarer all informasjon i eposten
390 (f.eks. Received-linjer). Finnes det en anbefalt XML-mapping ala den
391 som beskrives på
392 &amp;lt;URL: &lt;a href=&quot;https://www.informit.com/articles/article.aspx?p=32074&quot;&gt;https://www.informit.com/articles/article.aspx?p=32074&lt;/a&gt; &amp;gt;? Mitt
393 mål er at det skal være mulig å lagre eposten i en NOARK5-kjerne og
394 kunne få ut en identisk formattert kopi av opprinnelig epost ved
395 behov.&lt;/p&gt;
396 &lt;/blockquote&gt;&lt;/p&gt;
397
398 &lt;p&gt;Postmottaker hos SAMDOK mente spørsmålet heller burde stilles
399 direkte til riksarkivet, og jeg fikk i dag svar derfra formulert av
400 seniorrådgiver Geir Ivar Tungesvik:&lt;/p&gt;
401
402 &lt;p&gt;&lt;blockquote&gt;
403 &lt;p&gt;Riksarkivet har ingen anbefalinger når det gjelder konvertering fra
404 e-post til XML. Det står arkivskaper fritt å eventuelt definere/bruke
405 eget format. Inklusive da - som det spørres om - et format der det er
406 mulig å re-etablere e-post format ut fra XML-en. XML (e-post)
407 dokumenter må være referert i arkivstrukturen, og det må vedlegges et
408 gyldig XML skjema (.xsd) for XML-filene. Arkivskaper står altså fritt
409 til å gjøre hva de vil, bare det dokumenteres og det kan dannes et
410 utrekk ved avlevering til depot.&lt;/p&gt;
411
412 &lt;p&gt;De obligatoriske kravene i Noark 5 standarden må altså oppfylles -
413 etter dialog med Riksarkivet i forbindelse med godkjenning. For
414 offentlige arkiv er det særlig viktig med filene loependeJournal.xml
415 og offentligJournal.xml. Private arkiv som vil forholde seg til Noark
416 5 standarden er selvsagt frie til å bruke det som er relevant for dem
417 av obligatoriske krav.&lt;/p&gt;
418 &lt;/blockquote&gt;&lt;/p&gt;
419
420 &lt;p&gt;Det ser dermed ut for meg som om det er et lite behov for å
421 standardisere XML-lagring av RFC-822-formatterte meldinger. Noen som
422 vet om god spesifikasjon i så måte? I tillegg til den omtalt over,
423 har jeg kommet over flere aktuelle beskrivelser (søk på &quot;rfc 822
424 xml&quot;, så finner du aktuelle alternativer).&lt;/p&gt;
425
426 &lt;ul&gt;
427
428 &lt;li&gt;&lt;a href=&quot;http://www.openhealth.org/xmtp/&quot;&gt;XML MIME Transformation
429 protocol (XMTP)&lt;/a&gt; fra OpenHealth, sist oppdatert 2001.&lt;/li&gt;
430
431 &lt;li&gt;&lt;a href=&quot;https://tools.ietf.org/html/draft-klyne-message-rfc822-xml-03&quot;&gt;An
432 XML format for mail and other messages&lt;/a&gt; utkast fra IETF datert
433 2001.&lt;/li&gt;
434
435 &lt;li&gt;&lt;a href=&quot;http://www.informit.com/articles/article.aspx?p=32074&quot;&gt;xMail:
436 E-mail as XML&lt;/a&gt; en artikkel fra 2003 som beskriver python-modulen
437 rfc822 som gir ut XML-representasjon av en RFC 822-formattert epost.&lt;/li&gt;
438
439 &lt;/ul&gt;
440
441 &lt;p&gt;Finnes det andre og bedre spesifikasjoner for slik lagring? Send
442 meg en epost hvis du har innspill.&lt;/p&gt;
443 </description>
444 </item>
445
446 <item>
447 <title>Lenker for 2014-02-28</title>
448 <link>http://people.skolelinux.org/pere/blog/Lenker_for_2014_02_28.html</link>
449 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Lenker_for_2014_02_28.html</guid>
450 <pubDate>Fri, 28 Feb 2014 13:30:00 +0100</pubDate>
451 <description>&lt;p&gt;Her er noen lenker til tekster jeg har satt pris på å lese de siste
452 månedene. Det er mye om varsleren Edward Snowden, som burde få all
453 hjelp, støtte og beskyttelse Norge kan stille opp med for å ha satt
454 totalitær overvåkning på sakskartet, men også endel annet
455 tankevekkende og interessant.&lt;/p&gt;
456
457 &lt;ul&gt;
458
459 &lt;li&gt;2013-12-21
460 &lt;a href=&quot;http://www.dagbladet.no/2013/12/21/nyheter/thomas_drake/nsa/overvakning/snowden/30925886/&quot;&gt;-
461 NSA tenker som Stasi&lt;/a&gt; - Dagbladet.no&lt;/li&gt;
462
463 &lt;li&gt;2013-12-19 &lt;a href=&quot;http://www.dagensit.no/article2732734.ece&quot;&gt;-
464 Staten har ikke rett til å vite alt om deg&lt;/a&gt; - DN.no&lt;/li&gt;
465
466 &lt;li&gt;2013-12-21
467 &lt;a href=&quot;http://www.dagbladet.no/2013/12/21/nyheter/krig_og_konflikter/politikk/utenriks/30961126/&quot;&gt;Nye
468 mål for NSAs spionasje avslørt&lt;/a&gt; - Dagbladet.no&lt;/li&gt;
469
470 &lt;li&gt;2013-12-19
471 &lt;a href=&quot;http://www.dagbladet.no/2013/12/19/nyheter/nsa/usa/politikk/barack_obama/30918684/&quot;&gt;«NSA
472 bør fjernes fra sin makt til å samle inn metadata fra amerikanske
473 telefonsamtaler»&lt;/a&gt; - Dagbladet.no&lt;/li&gt;
474
475 &lt;li&gt;2013-12-18
476 &lt;a href=&quot;http://www.dagbladet.no/2013/12/18/kultur/meninger/hovedkronikk/debatt/snowden/30901089/&quot;&gt;Etterretning,
477 overvåking, frihet og sikkerhet&lt;/a&gt; - Dagbladet.no&lt;/li&gt;
478
479 &lt;li&gt;2013-12-17
480 &lt;a href=&quot;http://www.nrk.no/verden/snowden-vil-ha-asyl-i-brasil-1.11423444&quot;&gt;Snowden
481 angriper USA i åpent brev&lt;/a&gt; - nrk.no&lt;/li&gt;
482
483 &lt;li&gt;2013-12-17
484 &lt;a href=&quot;http://www.digi.no/925820/rettslig-nederlag-for-etterretning&quot;&gt;Rettslig
485 nederlag for etterretning&lt;/a&gt; - digi.no&lt;/li&gt;
486
487 &lt;li&gt;2013-12-21
488 &lt;a href=&quot;http://www.dagbladet.no/2013/12/21/kultur/meninger/hovedkommentar/kommentar/etterretning/30963284/&quot;&gt;Truende
489 nedkjøling&lt;/a&gt; - dagbladet.no&lt;/li&gt;
490
491 &lt;li&gt;2013-12-20
492 &lt;a href=&quot;http://www.aftenposten.no/viten/Matematikk-og-forstaelse-7411849.html&quot;&gt;Matematikk
493 og forståelse&lt;/a&gt; - aftenposten.no&lt;/li&gt;
494
495 &lt;li&gt;2013-10-20
496 &lt;a href=&quot;http://www.nrk.no/viten/ny-studie_sovn-reinser-hjernen-var-1.11306106&quot;&gt;Vi
497 søv for å reinse hjernen vår, ifølgje ny studie&lt;/a&gt; - nrk.no&lt;/li&gt;
498
499 &lt;li&gt;2013-12-11
500 &lt;a href=&quot;http://www.nrk.no/buskerud/julebaksten-i-vasken-1.11410033&quot;&gt;Rotterace
501 i kloakken&lt;/a&gt; - nrk.no&lt;/li&gt;
502
503 &lt;li&gt;2013-12-30
504 &lt;a href=&quot;http://www.aftenposten.no/viten/Apne-brev-og-frie-tanker-7413734.html&quot;&gt;Åpne
505 brev og frie tanker&lt;/a&gt; - aftenposten.no&lt;/li&gt;
506
507 &lt;li&gt;2014-01-12
508 &lt;a href=&quot;http://www.aftenposten.no/viten/Stopp-kunnskapsapartheidet-7428229.html&quot;&gt;Stopp dagens kunnskapsapartheid!&lt;/a&gt; - aftenposten.no&lt;/li&gt;
509
510 &lt;li&gt;2014-01-09
511 &lt;a href=&quot;http://www.aftenposten.no/nyheter/uriks/EU-rapport-Britisk-og-amerikansk-overvaking-ser-ut-til-a-vare-ulovlig-7428933.html&quot;&gt;EU-rapport:
512 Britisk og amerikansk overvåking ser ut til å være ulovlig&lt;/a&gt; -
513 aftenposten.no&lt;/li&gt;
514
515 &lt;li&gt;2013-10-23 Professor Jan Arild Audestad
516 &lt;a href=&quot;http://www.digi.no/924008/advarer-mot-konspirasjonsteori&quot;&gt;Advarer
517 mot konspirasjonsteori&lt;/a&gt; i digi.no og sier han ikke tror NSA kan
518 avlytte mobiltelefoner, mens han noen måneder senere forteller:&lt;/li&gt;
519
520 &lt;li&gt;2014-01-09
521 &lt;a href=&quot;http://www.aftenposten.no/nyheter/iriks/--Vi-ble-presset-til-a-svekke-mobilsikkerheten-pa-80-tallet-7410467.html&quot;&gt;-
522 Vi ble presset til å svekke mobilsikkerheten på 80-tallet&lt;/a&gt; -
523 aftenposten.no&lt;/li&gt;
524
525 &lt;li&gt;2014-02-12
526 &lt;a href=&quot;http://tv.nrk.no/program/koid20005814/et-moete-med-edward-snowden&quot;&gt;Et
527 møte med Edward Snowden&lt;/a&gt; - intervju sendt av nrk, tilgjengelig til
528 2015-01-31&lt;/li&gt;
529
530 &lt;li&gt;2014-02-17
531 &lt;a href=&quot;http://politiken.dk/debat/profiler/jessteinpedersen/ECE2210356/litteraturredaktoeren-helle-thornings-tavshed-om-snowden-er-en-skandale/&quot;&gt;Litteraturredaktøren:
532 Helle Thornings tavshed om Snowden er en skandale&lt;/a&gt; -
533 politiken.dk&lt;/li&gt;
534
535 &lt;li&gt;2014-02-21
536 &lt;a href=&quot;http://www.aftenposten.no/meninger/kronikker/Bra-a-ha-en-Storebror-7476734.html&quot;&gt;Bra å ha en «Storebror»&lt;/a&gt; - aftenposten.no&lt;/li&gt;
537
538 &lt;li&gt;2014-02-28
539 &lt;a href=&quot;http://johnchristianelden.blogg.no/1393536806_narkotikasiktet_stort.html&quot;&gt;&quot;Narkotikasiktet
540 Stortingsmann&quot; - Spillet bak kulissene&lt;/a&gt; - John Christian Eldens
541 blogg&lt;/li&gt;
542
543 &lt;li&gt;2014-02-28
544 &lt;a href=&quot;http://www.aftenposten.no/meninger/Heksejakt-pa-hasjbrukere-7486283.html&quot;&gt;Heksejakt
545 på hasjbrukere&lt;/a&gt; - aftenposten.no&lt;/li&gt;
546
547 &lt;/ul&gt;
548 </description>
549 </item>
550
551 <item>
552 <title>New home and release 1.0 for netgroup and innetgr (aka ng-utils)</title>
553 <link>http://people.skolelinux.org/pere/blog/New_home_and_release_1_0_for_netgroup_and_innetgr__aka_ng_utils_.html</link>
554 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/New_home_and_release_1_0_for_netgroup_and_innetgr__aka_ng_utils_.html</guid>
555 <pubDate>Sat, 22 Feb 2014 21:45:00 +0100</pubDate>
556 <description>&lt;p&gt;Many years ago, I wrote a GPL licensed version of the netgroup and
557 innetgr tools, because I needed them in
558 &lt;a href=&quot;http://www.skolelinux.org/&quot;&gt;Skolelinux&lt;/a&gt;. I called the project
559 ng-utils, and it has served me well. I placed the project under the
560 &lt;a href=&quot;http://www.hungry.com/&quot;&gt;Hungry Programmer&lt;/a&gt; umbrella, and it was maintained in our CVS
561 repository. But many years ago, the CVS repository was dropped (lost,
562 not migrated to new hardware, not sure), and the project have lacked a
563 proper home since then.&lt;/p&gt;
564
565 &lt;p&gt;Last summer, I had a look at the package and made a new release
566 fixing a irritating crash bug, but was unable to store the changes in
567 a proper source control system. I applied for a project on
568 &lt;a href=&quot;https://alioth.debian.org/&quot;&gt;Alioth&lt;/a&gt;, but did not have time
569 to follow up on it. Until today. :)&lt;/p&gt;
570
571 &lt;p&gt;After many hours of cleaning and migration, the ng-utils project
572 now have a new home, and a git repository with the highlight of the
573 history of the project. I published all release tarballs and imported
574 them into the git repository. As the project is really stable and not
575 expected to gain new features any time soon, I decided to make a new
576 release and call it 1.0. Visit the new project home on
577 &lt;a href=&quot;https://alioth.debian.org/projects/ng-utils/&quot;&gt;https://alioth.debian.org/projects/ng-utils/&lt;/a&gt;
578 if you want to check it out. The new version is also uploaded into
579 &lt;a href=&quot;http://packages.qa.debian.org/n/ng-utils.html&quot;&gt;Debian Unstable&lt;/a&gt;.&lt;/p&gt;
580 </description>
581 </item>
582
583 <item>
584 <title>Testing sysvinit from experimental in Debian Hurd</title>
585 <link>http://people.skolelinux.org/pere/blog/Testing_sysvinit_from_experimental_in_Debian_Hurd.html</link>
586 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Testing_sysvinit_from_experimental_in_Debian_Hurd.html</guid>
587 <pubDate>Mon, 3 Feb 2014 13:40:00 +0100</pubDate>
588 <description>&lt;p&gt;A few days ago I decided to try to help the Hurd people to get
589 their changes into sysvinit, to allow them to use the normal sysvinit
590 boot system instead of their old one. This follow up on the
591 &lt;a href=&quot;https://teythoon.cryptobitch.de//categories/gsoc.html&quot;&gt;great
592 Google Summer of Code work&lt;/a&gt; done last summer by Justus Winter to
593 get Debian on Hurd working more like Debian on Linux. To get started,
594 I downloaded a prebuilt hard disk image from
595 &lt;a href=&quot;http://ftp.debian-ports.org/debian-cd/hurd-i386/current/debian-hurd.img.tar.gz&quot;&gt;http://ftp.debian-ports.org/debian-cd/hurd-i386/current/debian-hurd.img.tar.gz&lt;/a&gt;,
596 and started it using virt-manager.&lt;/p&gt;
597
598 &lt;p&gt;The first think I had to do after logging in (root without any
599 password) was to get the network operational. I followed
600 &lt;a href=&quot;https://www.debian.org/ports/hurd/hurd-install&quot;&gt;the
601 instructions on the Debian GNU/Hurd ports page&lt;/a&gt; and ran these
602 commands as root to get the machine to accept a IP address from the
603 kvm internal DHCP server:&lt;/p&gt;
604
605 &lt;p&gt;&lt;blockquote&gt;&lt;pre&gt;
606 settrans -fgap /dev/netdde /hurd/netdde
607 kill $(ps -ef|awk &#39;/[p]finet/ { print $2}&#39;)
608 kill $(ps -ef|awk &#39;/[d]evnode/ { print $2}&#39;)
609 dhclient /dev/eth0
610 &lt;/pre&gt;&lt;/blockquote&gt;&lt;/p&gt;
611
612 &lt;p&gt;After this, the machine had internet connectivity, and I could
613 upgrade it and install the sysvinit packages from experimental and
614 enable it as the default boot system in Hurd.&lt;/p&gt;
615
616 &lt;p&gt;But before I did that, I set a password on the root user, as ssh is
617 running on the machine it for ssh login to work a password need to be
618 set. Also, note that a bug somewhere in openssh on Hurd block
619 compression from working. Remember to turn that off on the client
620 side.&lt;/p&gt;
621
622 &lt;p&gt;Run these commands as root to upgrade and test the new sysvinit
623 stuff:&lt;/p&gt;
624
625 &lt;p&gt;&lt;blockquote&gt;&lt;pre&gt;
626 cat &gt; /etc/apt/sources.list.d/experimental.list &amp;lt;&amp;lt;EOF
627 deb http://http.debian.net/debian/ experimental main
628 EOF
629 apt-get update
630 apt-get dist-upgrade
631 apt-get install -t experimental initscripts sysv-rc sysvinit \
632 sysvinit-core sysvinit-utils
633 update-alternatives --config runsystem
634 &lt;/pre&gt;&lt;/blockquote&gt;&lt;/p&gt;
635
636 &lt;p&gt;To reboot after switching boot system, you have to use
637 &lt;tt&gt;reboot-hurd&lt;/tt&gt; instead of just &lt;tt&gt;reboot&lt;/tt&gt;, as there is not
638 yet a sysvinit process able to receive the signals from the normal
639 &#39;reboot&#39; command. After switching to sysvinit as the boot system,
640 upgrading every package and rebooting, the network come up with DHCP
641 after boot as it should, and the settrans/pkill hack mentioned at the
642 start is no longer needed. But for some strange reason, there are no
643 longer any login prompt in the virtual console, so I logged in using
644 ssh instead.
645
646 &lt;p&gt;Note that there are some race conditions in Hurd making the boot
647 fail some times. No idea what the cause is, but hope the Hurd porters
648 figure it out. At least Justus said on IRC (#debian-hurd on
649 irc.debian.org) that they are aware of the problem. A way to reduce
650 the impact is to upgrade to the Hurd packages built by Justus by
651 adding this repository to the machine:&lt;/p&gt;
652
653 &lt;p&gt;&lt;blockquote&gt;&lt;pre&gt;
654 cat &gt; /etc/apt/sources.list.d/hurd-ci.list &amp;lt;&amp;lt;EOF
655 deb http://darnassus.sceen.net/~teythoon/hurd-ci/ sid main
656 EOF
657 &lt;/pre&gt;&lt;/blockquote&gt;&lt;/p&gt;
658
659 &lt;p&gt;At the moment the prebuilt virtual machine get some packages from
660 http://ftp.debian-ports.org/debian, because some of the packages in
661 unstable do not yet include the required patches that are lingering in
662 BTS. This is the completely list of &quot;unofficial&quot; packages installed:&lt;/p&gt;
663
664 &lt;p&gt;&lt;blockquote&gt;&lt;pre&gt;
665 # aptitude search &#39;?narrow(?version(CURRENT),?origin(Debian Ports))&#39;
666 i emacs - GNU Emacs editor (metapackage)
667 i gdb - GNU Debugger
668 i hurd-recommended - Miscellaneous translators
669 i isc-dhcp-client - ISC DHCP client
670 i isc-dhcp-common - common files used by all the isc-dhcp* packages
671 i libc-bin - Embedded GNU C Library: Binaries
672 i libc-dev-bin - Embedded GNU C Library: Development binaries
673 i libc0.3 - Embedded GNU C Library: Shared libraries
674 i A libc0.3-dbg - Embedded GNU C Library: detached debugging symbols
675 i libc0.3-dev - Embedded GNU C Library: Development Libraries and Hea
676 i multiarch-support - Transitional package to ensure multiarch compatibilit
677 i A x11-common - X Window System (X.Org) infrastructure
678 i xorg - X.Org X Window System
679 i A xserver-xorg - X.Org X server
680 i A xserver-xorg-input-all - X.Org X server -- input driver metapackage
681 #
682 &lt;/pre&gt;&lt;/blockquote&gt;&lt;/p&gt;
683
684 &lt;p&gt;All in all, testing hurd has been an interesting experience. :)
685 X.org did not work out of the box and I never took the time to follow
686 the porters instructions to fix it. This time I was interested in the
687 command line stuff.&lt;p&gt;
688 </description>
689 </item>
690
691 <item>
692 <title>A fist full of non-anonymous Bitcoins</title>
693 <link>http://people.skolelinux.org/pere/blog/A_fist_full_of_non_anonymous_Bitcoins.html</link>
694 <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/A_fist_full_of_non_anonymous_Bitcoins.html</guid>
695 <pubDate>Wed, 29 Jan 2014 14:10:00 +0100</pubDate>
696 <description>&lt;p&gt;Bitcoin is a incredible use of peer to peer communication and
697 encryption, allowing direct and immediate money transfer without any
698 central control. It is sometimes claimed to be ideal for illegal
699 activity, which I believe is quite a long way from the truth. At least
700 I would not conduct illegal money transfers using a system where the
701 details of every transaction are kept forever. This point is
702 investigated in
703 &lt;a href=&quot;https://www.usenix.org/publications/login&quot;&gt;USENIX ;login:&lt;/a&gt;
704 from December 2013, in the article
705 &quot;&lt;a href=&quot;https://www.usenix.org/system/files/login/articles/03_meiklejohn-online.pdf&quot;&gt;A
706 Fistful of Bitcoins - Characterizing Payments Among Men with No
707 Names&lt;/a&gt;&quot; by Sarah Meiklejohn, Marjori Pomarole,Grant Jordan, Kirill
708 Levchenko, Damon McCoy, Geoffrey M. Voelker, and Stefan Savage. They
709 analyse the transaction log in the Bitcoin system, using it to find
710 addresses belong to individuals and organisations and follow the flow
711 of money from both Bitcoin theft and trades on Silk Road to where the
712 money end up. This is how they wrap up their article:&lt;/p&gt;
713
714 &lt;p&gt;&lt;blockquote&gt;
715 &lt;p&gt;&quot;To demonstrate the usefulness of this type of analysis, we turned
716 our attention to criminal activity. In the Bitcoin economy, criminal
717 activity can appear in a number of forms, such as dealing drugs on
718 Silk Road or simply stealing someone else’s bitcoins. We followed the
719 flow of bitcoins out of Silk Road (in particular, from one notorious
720 address) and from a number of highly publicized thefts to see whether
721 we could track the bitcoins to known services. Although some of the
722 thieves attempted to use sophisticated mixing techniques (or possibly
723 mix services) to obscure the flow of bitcoins, for the most part
724 tracking the bitcoins was quite straightforward, and we ultimately saw
725 large quantities of bitcoins flow to a variety of exchanges directly
726 from the point of theft (or the withdrawal from Silk Road).&lt;/p&gt;
727
728 &lt;p&gt;As acknowledged above, following stolen bitcoins to the point at
729 which they are deposited into an exchange does not in itself identify
730 the thief; however, it does enable further de-anonymization in the
731 case in which certain agencies can determine (through, for example,
732 subpoena power) the real-world owner of the account into which the
733 stolen bitcoins were deposited. Because such exchanges seem to serve
734 as chokepoints into and out of the Bitcoin economy (i.e., there are
735 few alternative ways to cash out), we conclude that using Bitcoin for
736 money laundering or other illicit purposes does not (at least at
737 present) seem to be particularly attractive.&quot;&lt;/p&gt;
738 &lt;/blockquote&gt;&lt;p&gt;
739
740 &lt;p&gt;These researches are not the first to analyse the Bitcoin
741 transaction log. The 2011 paper
742 &quot;&lt;a href=&quot;http://arxiv.org/abs/1107.4524&quot;&gt;An Analysis of Anonymity in
743 the Bitcoin System&lt;/A&gt;&quot; by Fergal Reid and Martin Harrigan is
744 summarized like this:&lt;/p&gt;
745
746 &lt;p&gt;&lt;blockquote&gt;
747 &quot;Anonymity in Bitcoin, a peer-to-peer electronic currency system, is a
748 complicated issue. Within the system, users are identified by
749 public-keys only. An attacker wishing to de-anonymize its users will
750 attempt to construct the one-to-many mapping between users and
751 public-keys and associate information external to the system with the
752 users. Bitcoin tries to prevent this attack by storing the mapping of
753 a user to his or her public-keys on that user&#39;s node only and by
754 allowing each user to generate as many public-keys as required. In
755 this chapter we consider the topological structure of two networks
756 derived from Bitcoin&#39;s public transaction history. We show that the
757 two networks have a non-trivial topological structure, provide
758 complementary views of the Bitcoin system and have implications for
759 anonymity. We combine these structures with external information and
760 techniques such as context discovery and flow analysis to investigate
761 an alleged theft of Bitcoins, which, at the time of the theft, had a
762 market value of approximately half a million U.S. dollars.&quot;
763 &lt;/blockquote&gt;&lt;/p&gt;
764
765 &lt;p&gt;I hope these references can help kill the urban myth that Bitcoin
766 is anonymous. It isn&#39;t really a good fit for illegal activites. Use
767 cash if you need to stay anonymous, at least until regular DNA
768 sampling of notes and coins become the norm. :)&lt;/p&gt;
769
770 &lt;p&gt;As usual, if you use Bitcoin and want to show your support of my
771 activities, please send Bitcoin donations to my address
772 &lt;b&gt;&lt;a href=&quot;bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b&amp;label=PetterReinholdtsenBlog&quot;&gt;15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b&lt;/a&gt;&lt;/b&gt;.&lt;/p&gt;
773 </description>
774 </item>
775
776 </channel>
777 </rss>