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  13  <h1>
  14      <a href="http://people.skolelinux.org/pere/blog/">Petter Reinholdtsen</a>
  15
  16  </h1>
  17
  18 </div>
  19
  20
  21
  22     <div class="entry">
  23       <div class="title"><a href="http://people.skolelinux.org/pere/blog/Install_hardware_dependent_packages_using_tasksel__Isenkram_0_7_.html">Install hardware dependent packages using tasksel (Isenkram 0.7)</a></div>
  24       <div class="date">23rd April 2014</div>
  25       <div class="body"><p>It would be nice if it was easier in Debian to get all the hardware
  26 related packages relevant for the computer installed automatically.
  27 So I implemented one, using
  28 <a href="http://packages.qa.debian.org/isenkram">my Isenkram
  29 package</a>.  To use it, install the tasksel and isenkram packages and
  30 run tasksel as user root.  You should be presented with a new option,
  31 "Hardware specific packages (autodetected by isenkram)".  When you
  32 select it, tasksel will install the packages isenkram claim is fit for
  33 the current hardware, hot pluggable or not.<p>
  34
  35 <p>The implementation is in two files, one is the tasksel menu entry
  36 description, and the other is the script used to extract the list of
  37 packages to install.  The first part is in
  38 <tt>/usr/share/tasksel/descs/isenkram.desc</tt> and look like
  39 this:</p>
  40
  41 <p><blockquote><pre>
  42 Task: isenkram
  43 Section: hardware
  44 Description: Hardware specific packages (autodetected by isenkram)
  45  Based on the detected hardware various hardware specific packages are
  46  proposed.
  47 Test-new-install: mark show
  48 Relevance: 8
  49 Packages: for-current-hardware
  50 </pre></blockquote></p>
  51
  52 <p>The second part is in
  53 <tt>/usr/lib/tasksel/packages/for-current-hardware</tt> and look like
  54 this:</p>
  55
  56 <p><blockquote><pre>
  57 #!/bin/sh
  58 #
  59 (
  60     isenkram-lookup
  61     isenkram-autoinstall-firmware -l
  62 ) | sort -u
  63 </pre></blockquote></p>
  64
  65 <p>All in all, a very short and simple implementation making it
  66 trivial to install the hardware dependent package we all may want to
  67 have installed on our machines.  I've not been able to find a way to
  68 get tasksel to tell you exactly which packages it plan to install
  69 before doing the installation.  So if you are curious or careful,
  70 check the output from the isenkram-* command line tools first.</p>
  71
  72 <p>The information about which packages are handling which hardware is
  73 fetched either from the isenkram package itself in
  74 /usr/share/isenkram/, from git.debian.org or from the APT package
  75 database (using the Modaliases header).  The APT package database
  76 parsing have caused a nasty resource leak in the isenkram daemon (bugs
  77 <a href="http://bugs.debian.org/719837">#719837</a> and
  78 <a href="http://bugs.debian.org/730704">#730704</a>).  The cause is in
  79 the python-apt code (bug
  80 <a href="http://bugs.debian.org/745487">#745487</a>), but using a
  81 workaround I was able to get rid of the file descriptor leak and
  82 reduce the memory leak from ~30 MiB per hardware detection down to
  83 around 2 miB per hardware detection.  It should make the desktop
  84 daemon a lot more useful.  The fix is in version 0.7 uploaded to
  85 unstable today.</p>
  86
  87 <p>I believe the current way of mapping hardware to packages in
  88 Isenkram is is a good draft, but in the future I expect isenkram to
  89 use the AppStream data source for this.  A proposal for getting proper
  90 AppStream support into Debian is floating around as
  91 <a href="https://wiki.debian.org/DEP-11">DEP-11</a>, and
  92 <a href="https://wiki.debian.org/SummerOfCode2014/Projects#SummerOfCode2014.2FProjects.2FAppStreamDEP11Implementation.AppStream.2FDEP-11_for_the_Debian_Archive">GSoC
  93 project</a> will take place this summer to improve the situation.  I
  94 look forward to seeing the result, and welcome patches for isenkram to
  95 start using the information when it is ready.</p>
  96
  97 <p>If you want your package to map to some specific hardware, either
  98 add a "Xb-Modaliases" header to your control file like I did in
  99 <a href="http://packages.qa.debian.org/pymissile">the pymissile
 100 package</a> or submit a bug report with the details to the isenkram
 101 package.  See also
 102 <a href="http://people.skolelinux.org/pere/blog/tags/isenkram/">all my
 103 blog posts tagged isenkram</a> for details on the notation.  I expect
 104 the information will be migrated to AppStream eventually, but for the
 105 moment I got no better place to store it.</p>
 106 </div>
 107       <div class="tags">
 108
 109
 110         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/isenkram">isenkram</a>.
 111
 112
 113       </div>
 114     </div>
 115     <div class="padding"></div>
 116
 117     <div class="entry">
 118       <div class="title"><a href="http://people.skolelinux.org/pere/blog/FreedomBox_milestone___all_packages_now_in_Debian_Sid.html">FreedomBox milestone - all packages now in Debian Sid</a></div>
 119       <div class="date">15th April 2014</div>
 120       <div class="body"><p>The <a href="https://wiki.debian.org/FreedomBox">Freedombox
 121 project</a> is working on providing the software and hardware to make
 122 it easy for non-technical people to host their data and communication
 123 at home, and being able to communicate with their friends and family
 124 encrypted and away from prying eyes.  It is still going strong, and
 125 today a major mile stone was reached.</p>
 126
 127 <p>Today, the last of the packages currently used by the project to
 128 created the system images were accepted into Debian Unstable.  It was
 129 the freedombox-setup package, which is used to configure the images
 130 during build and on the first boot.  Now all one need to get going is
 131 the build code from the freedom-maker git repository and packages from
 132 Debian.  And once the freedombox-setup package enter testing, we can
 133 build everything directly from Debian. :)</p>
 134
 135 <p>Some key packages used by Freedombox are
 136 <a href="http://packages.qa.debian.org/freedombox-setup">freedombox-setup</a>,
 137 <a href="http://packages.qa.debian.org/plinth">plinth</a>,
 138 <a href="http://packages.qa.debian.org/pagekite">pagekite</a>,
 139 <a href="http://packages.qa.debian.org/tor">tor</a>,
 140 <a href="http://packages.qa.debian.org/privoxy">privoxy</a>,
 141 <a href="http://packages.qa.debian.org/owncloud">owncloud</a> and
 142 <a href="http://packages.qa.debian.org/dnsmasq">dnsmasq</a>.  There
 143 are plans to integrate more packages into the setup.  User
 144 documentation is maintained on the Debian wiki.  Please
 145 <a href="https://wiki.debian.org/FreedomBox/Manual/Jessie">check out
 146 the manual</a> and help us improve it.</p>
 147
 148 <p>To test for yourself and create boot images with the FreedomBox
 149 setup, run this on a Debian machine using a user with sudo rights to
 150 become root:</p>
 151
 152 <p><pre>
 153 sudo apt-get install git vmdebootstrap mercurial python-docutils \
 154   mktorrent extlinux virtualbox qemu-user-static binfmt-support \
 155   u-boot-tools
 156 git clone http://anonscm.debian.org/git/freedombox/freedom-maker.git \
 157   freedom-maker
 158 make -C freedom-maker dreamplug-image raspberry-image virtualbox-image
 159 </pre></p>
 160
 161 <p>Root access is needed to run debootstrap and mount loopback
 162 devices.  See the README in the freedom-maker git repo for more
 163 details on the build.  If you do not want all three images, trim the
 164 make line.  Note that the virtualbox-image target is not really
 165 virtualbox specific.  It create a x86 image usable in kvm, qemu,
 166 vmware and any other x86 virtual machine environment.  You might need
 167 the version of vmdebootstrap in Jessie to get the build working, as it
 168 include fixes for a race condition with kpartx.</p>
 169
 170 <p>If you instead want to install using a Debian CD and the preseed
 171 method, boot a Debian Wheezy ISO and use this boot argument to load
 172 the preseed values:</p>
 173
 174 <p><pre>
 175 url=<a href="http://www.reinholdtsen.name/freedombox/preseed-jessie.dat">http://www.reinholdtsen.name/freedombox/preseed-jessie.dat</a>
 176 </pre></p>
 177
 178 <p>I have not tested it myself the last few weeks, so I do not know if
 179 it still work.</p>
 180
 181 <p>If you wonder how to help, one task you could look at is using
 182 systemd as the boot system.  It will become the default for Linux in
 183 Jessie, so we need to make sure it is usable on the Freedombox.  I did
 184 a simple test a few weeks ago, and noticed dnsmasq failed to start
 185 during boot when using systemd.  I suspect there are other problems
 186 too. :) To detect problems, there is a test suite included, which can
 187 be run from the plinth web interface.</p>
 188
 189 <p>Give it a go and let us know how it goes on the mailing list, and help
 190 us get the new release published. :) Please join us on
 191 <a href="irc://irc.debian.org:6667/%23freedombox">IRC (#freedombox on
 192 irc.debian.org)</a> and
 193 <a href="http://lists.alioth.debian.org/mailman/listinfo/freedombox-discuss">the
 194 mailing list</a> if you want to help make this vision come true.</p>
 195 </div>
 196       <div class="tags">
 197
 198
 199         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/freedombox">freedombox</a>, <a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet</a>, <a href="http://people.skolelinux.org/pere/blog/tags/surveillance">surveillance</a>, <a href="http://people.skolelinux.org/pere/blog/tags/web">web</a>.
 200
 201
 202       </div>
 203     </div>
 204     <div class="padding"></div>
 205
 206     <div class="entry">
 207       <div class="title"><a href="http://people.skolelinux.org/pere/blog/Spr_kkoder_for_POSIX_locale_i_Norge.html">Språkkoder for POSIX locale i Norge</a></div>
 208       <div class="date">11th April 2014</div>
 209       <div class="body"><p>For 12 år siden, skrev jeg et lite notat om
 210 <a href="http://i18n.skolelinux.no/localekoder.txt">bruk av språkkoder
 211 i Norge</a>.  Jeg ble nettopp minnet på dette da jeg fikk spørsmål om
 212 notatet fortsatt var aktuelt, og tenkte det var greit å repetere hva
 213 som fortsatt gjelder.  Det jeg skrev da er fortsatt like aktuelt.</p>
 214
 215 <p>Når en velger språk i programmer på unix, så velger en blant mange
 216 språkkoder.  For språk i Norge anbefales følgende språkkoder (anbefalt
 217 locale i parantes):</p>
 218
 219 <p><dl>
 220 <dt>nb (nb_NO)</dt><dd>Bokmål i Norge</dd>
 221 <dt>nn (nn_NO)</dt><dd>Nynorsk i Norge</dd>
 222 <dt>se (se_NO)</dt><dd>Nordsamisk i Norge</dd>
 223 </dl></p>
 224
 225 <p>Alle programmer som bruker andre koder bør endres.</p>
 226
 227 <p>Språkkoden bør brukes når .po-filer navngis og installeres.  Dette
 228 er ikke det samme som locale-koden.  For Norsk Bokmål, så bør filene
 229 være navngitt nb.po, mens locale (LANG) bør være nb_NO.</p>
 230
 231 <p>Hvis vi ikke får standardisert de kodene i alle programmene med
 232 norske oversettelser, så er det umulig å gi LANG-variablen ett innhold
 233 som fungerer for alle programmer.</p>
 234
 235 <p>Språkkodene er de offisielle kodene fra ISO 639, og bruken av dem i
 236 forbindelse med POSIX localer er standardisert i RFC 3066 og ISO
 237 15897.  Denne anbefalingen er i tråd med de angitte standardene.</p>
 238
 239 <p>Følgende koder er eller har vært i bruk som locale-verdier for
 240 "norske" språk.  Disse bør unngås, og erstattes når de oppdages:</p>
 241
 242 <p><table>
 243 <tr><td>norwegian</td><td>-> nb_NO</td></tr>
 244 <tr><td>bokmål   </td><td>-> nb_NO</td></tr>
 245 <tr><td>bokmal   </td><td>-> nb_NO</td></tr>
 246 <tr><td>nynorsk  </td><td>-> nn_NO</td></tr>
 247 <tr><td>no       </td><td>-> nb_NO</td></tr>
 248 <tr><td>no_NO    </td><td>-> nb_NO</td></tr>
 249 <tr><td>no_NY    </td><td>-> nn_NO</td></tr>
 250 <tr><td>sme_NO   </td><td>-> se_NO</td></tr>
 251 </table></p>
 252
 253 <p>Merk at når det gjelder de samiske språkene, at se_NO i praksis
 254 henviser til nordsamisk i Norge, mens f.eks.  smj_NO henviser til
 255 lulesamisk.  Dette notatet er dog ikke ment å gi råd rundt samiske
 256 språkkoder, der gjør
 257 <a href="http://www.divvun.no/">Divvun-prosjektet</a> en bedre
 258 jobb.</p>
 259
 260 <p><strong>Referanser:</strong></p>
 261
 262 <ul>
 263
 264   <li><a href="http://www.rfc-base.org/rfc-3066.html">RFC 3066 - Tags
 265     for the Identification of Languages</a> (Erstatter RFC 1766)</li>
 266
 267   <li><a href="http://www.loc.gov/standards/iso639-2/langcodes.html">ISO
 268     639</a> - Codes for the Representation of Names of Languages</li>
 269
 270   <li><a href="http://std.dkuug.dk/jtc1/sc22/wg20/docs/n897-14652w25.pdf">ISO
 271     DTR 14652</a> - locale-standard Specification method for cultural
 272     conventions</li>
 273
 274   <li><a href="http://std.dkuug.dk/jtc1/sc22/wg20/docs/n610.pdf">ISO
 275     15897: Registration procedures for cultural elements (cultural
 276     registry)</a>,
 277     <a href="http://std.dkuug.dk/jtc1/sc22/wg20/docs/n849-15897wd6.pdf">(nytt
 278     draft)</a></li>
 279
 280   <li><a href="http://std.dkuug.dk/jtc1/sc22/wg20/">ISO/IEC
 281     JTC1/SC22/WG20</a> - Gruppen for i18n-standardisering i ISO</li>
 282
 283 <ul>
 284 </div>
 285       <div class="tags">
 286
 287
 288         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk</a>.
 289
 290
 291       </div>
 292     </div>
 293     <div class="padding"></div>
 294
 295     <div class="entry">
 296       <div class="title"><a href="http://people.skolelinux.org/pere/blog/S3QL__a_locally_mounted_cloud_file_system___nice_free_software.html">S3QL, a locally mounted cloud file system - nice free software</a></div>
 297       <div class="date"> 9th April 2014</div>
 298       <div class="body"><p>For a while now, I have been looking for a sensible offsite backup
 299 solution for use at home.  My requirements are simple, it must be
 300 cheap and locally encrypted (in other words, I keep the encryption
 301 keys, the storage provider do not have access to my private files).
 302 One idea me and my friends had many years ago, before the cloud
 303 storage providers showed up, was to use Google mail as storage,
 304 writing a Linux block device storing blocks as emails in the mail
 305 service provided by Google, and thus get heaps of free space.  On top
 306 of this one can add encryption, RAID and volume management to have
 307 lots of (fairly slow, I admit that) cheap and encrypted storage.  But
 308 I never found time to implement such system.  But the last few weeks I
 309 have looked at a system called
 310 <a href="https://bitbucket.org/nikratio/s3ql/">S3QL</a>, a locally
 311 mounted network backed file system with the features I need.</p>
 312
 313 <p>S3QL is a fuse file system with a local cache and cloud storage,
 314 handling several different storage providers, any with Amazon S3,
 315 Google Drive or OpenStack API.  There are heaps of such storage
 316 providers.  S3QL can also use a local directory as storage, which
 317 combined with sshfs allow for file storage on any ssh server.  S3QL
 318 include support for encryption, compression, de-duplication, snapshots
 319 and immutable file systems, allowing me to mount the remote storage as
 320 a local mount point, look at and use the files as if they were local,
 321 while the content is stored in the cloud as well.  This allow me to
 322 have a backup that should survive fire.  The file system can not be
 323 shared between several machines at the same time, as only one can
 324 mount it at the time, but any machine with the encryption key and
 325 access to the storage service can mount it if it is unmounted.</p>
 326
 327 <p>It is simple to use.  I'm using it on Debian Wheezy, where the
 328 package is included already.  So to get started, run <tt>apt-get
 329 install s3ql</tt>.  Next, pick a storage provider.  I ended up picking
 330 Greenqloud, after reading their nice recipe on
 331 <a href="https://greenqloud.zendesk.com/entries/44611757-How-To-Use-S3QL-to-mount-a-StorageQloud-bucket-on-Debian-Wheezy">how
 332 to use S3QL with their Amazon S3 service</a>, because I trust the laws
 333 in Iceland more than those in USA when it come to keeping my personal
 334 data safe and private, and thus would rather spend money on a company
 335 in Iceland.  Another nice recipe is available from the article
 336 <a href="http://www.admin-magazine.com/HPC/Articles/HPC-Cloud-Storage">S3QL
 337 Filesystem for HPC Storage</a> by Jeff Layton in the HPC section of
 338 Admin magazine.  When the provider is picked, figure out how to get
 339 the API key needed to connect to the storage API.  With Greencloud,
 340 the key did not show up until I had added payment details to my
 341 account.</p>
 342
 343 <p>Armed with the API access details, it is time to create the file
 344 system.  First, create a new bucket in the cloud.  This bucket is the
 345 file system storage area.  I picked a bucket name reflecting the
 346 machine that was going to store data there, but any name will do.
 347 I'll refer to it as <tt>bucket-name</tt> below.  In addition, one need
 348 the API login and password, and a locally created password.  Store it
 349 all in ~root/.s3ql/authinfo2 like this:
 350
 351 <p><blockquote><pre>
 352 [s3c]
 353 storage-url: s3c://s.greenqloud.com:443/bucket-name
 354 backend-login: API-login
 355 backend-password: API-password
 356 fs-passphrase: local-password
 357 </pre></blockquote></p>
 358
 359 <p>I create my local passphrase using <tt>pwget 50</tt> or similar,
 360 but any sensible way to create a fairly random password should do it.
 361 Armed with these details, it is now time to run mkfs, entering the API
 362 details and password to create it:</p>
 363
 364 <p><blockquote><pre>
 365 # mkdir -m 700 /var/lib/s3ql-cache
 366 # mkfs.s3ql --cachedir /var/lib/s3ql-cache --authfile /root/.s3ql/authinfo2 \
 367   --ssl s3c://s.greenqloud.com:443/bucket-name
 368 Enter backend login:
 369 Enter backend password:
 370 Before using S3QL, make sure to read the user's guide, especially
 371 the 'Important Rules to Avoid Loosing Data' section.
 372 Enter encryption password:
 373 Confirm encryption password:
 374 Generating random encryption key...
 375 Creating metadata tables...
 376 Dumping metadata...
 377 ..objects..
 378 ..blocks..
 379 ..inodes..
 380 ..inode_blocks..
 381 ..symlink_targets..
 382 ..names..
 383 ..contents..
 384 ..ext_attributes..
 385 Compressing and uploading metadata...
 386 Wrote 0.00 MB of compressed metadata.
 387 # </pre></blockquote></p>
 388
 389 <p>The next step is mounting the file system to make the storage available.
 390
 391 <p><blockquote><pre>
 392 # mount.s3ql --cachedir /var/lib/s3ql-cache --authfile /root/.s3ql/authinfo2 \
 393   --ssl --allow-root s3c://s.greenqloud.com:443/bucket-name /s3ql
 394 Using 4 upload threads.
 395 Downloading and decompressing metadata...
 396 Reading metadata...
 397 ..objects..
 398 ..blocks..
 399 ..inodes..
 400 ..inode_blocks..
 401 ..symlink_targets..
 402 ..names..
 403 ..contents..
 404 ..ext_attributes..
 405 Mounting filesystem...
 406 # df -h /s3ql
 407 Filesystem                              Size  Used Avail Use% Mounted on
 408 s3c://s.greenqloud.com:443/bucket-name  1.0T     0  1.0T   0% /s3ql
 409 #
 410 </pre></blockquote></p>
 411
 412 <p>The file system is now ready for use.  I use rsync to store my
 413 backups in it, and as the metadata used by rsync is downloaded at
 414 mount time, no network traffic (and storage cost) is triggered by
 415 running rsync.  To unmount, one should not use the normal umount
 416 command, as this will not flush the cache to the cloud storage, but
 417 instead running the umount.s3ql command like this:
 418
 419 <p><blockquote><pre>
 420 # umount.s3ql /s3ql
 421 #
 422 </pre></blockquote></p>
 423
 424 <p>There is a fsck command available to check the file system and
 425 correct any problems detected.  This can be used if the local server
 426 crashes while the file system is mounted, to reset the "already
 427 mounted" flag.  This is what it look like when processing a working
 428 file system:</p>
 429
 430 <p><blockquote><pre>
 431 # fsck.s3ql --force --ssl s3c://s.greenqloud.com:443/bucket-name
 432 Using cached metadata.
 433 File system seems clean, checking anyway.
 434 Checking DB integrity...
 435 Creating temporary extra indices...
 436 Checking lost+found...
 437 Checking cached objects...
 438 Checking names (refcounts)...
 439 Checking contents (names)...
 440 Checking contents (inodes)...
 441 Checking contents (parent inodes)...
 442 Checking objects (reference counts)...
 443 Checking objects (backend)...
 444 ..processed 5000 objects so far..
 445 ..processed 10000 objects so far..
 446 ..processed 15000 objects so far..
 447 Checking objects (sizes)...
 448 Checking blocks (referenced objects)...
 449 Checking blocks (refcounts)...
 450 Checking inode-block mapping (blocks)...
 451 Checking inode-block mapping (inodes)...
 452 Checking inodes (refcounts)...
 453 Checking inodes (sizes)...
 454 Checking extended attributes (names)...
 455 Checking extended attributes (inodes)...
 456 Checking symlinks (inodes)...
 457 Checking directory reachability...
 458 Checking unix conventions...
 459 Checking referential integrity...
 460 Dropping temporary indices...
 461 Backing up old metadata...
 462 Dumping metadata...
 463 ..objects..
 464 ..blocks..
 465 ..inodes..
 466 ..inode_blocks..
 467 ..symlink_targets..
 468 ..names..
 469 ..contents..
 470 ..ext_attributes..
 471 Compressing and uploading metadata...
 472 Wrote 0.89 MB of compressed metadata.
 473 #
 474 </pre></blockquote></p>
 475
 476 <p>Thanks to the cache, working on files that fit in the cache is very
 477 quick, about the same speed as local file access.  Uploading large
 478 amount of data is to me limited by the bandwidth out of and into my
 479 house.  Uploading 685 MiB with a 100 MiB cache gave me 305 kiB/s,
 480 which is very close to my upload speed, and downloading the same
 481 Debian installation ISO gave me 610 kiB/s, close to my download speed.
 482 Both were measured using <tt>dd</tt>.  So for me, the bottleneck is my
 483 network, not the file system code.  I do not know what a good cache
 484 size would be, but suspect that the cache should e larger than your
 485 working set.</p>
 486
 487 <p>I mentioned that only one machine can mount the file system at the
 488 time.  If another machine try, it is told that the file system is
 489 busy:</p>
 490
 491 <p><blockquote><pre>
 492 # mount.s3ql --cachedir /var/lib/s3ql-cache --authfile /root/.s3ql/authinfo2 \
 493   --ssl --allow-root s3c://s.greenqloud.com:443/bucket-name /s3ql
 494 Using 8 upload threads.
 495 Backend reports that fs is still mounted elsewhere, aborting.
 496 #
 497 </pre></blockquote></p>
 498
 499 <p>The file content is uploaded when the cache is full, while the
 500 metadata is uploaded once every 24 hour by default.  To ensure the
 501 file system content is flushed to the cloud, one can either umount the
 502 file system, or ask S3QL to flush the cache and metadata using
 503 s3qlctrl:
 504
 505 <p><blockquote><pre>
 506 # s3qlctrl upload-meta /s3ql
 507 # s3qlctrl flushcache /s3ql
 508 #
 509 </pre></blockquote></p>
 510
 511 <p>If you are curious about how much space your data uses in the
 512 cloud, and how much compression and deduplication cut down on the
 513 storage usage, you can use s3qlstat on the mounted file system to get
 514 a report:</p>
 515
 516 <p><blockquote><pre>
 517 # s3qlstat /s3ql
 518 Directory entries:    9141
 519 Inodes:               9143
 520 Data blocks:          8851
 521 Total data size:      22049.38 MB
 522 After de-duplication: 21955.46 MB (99.57% of total)
 523 After compression:    21877.28 MB (99.22% of total, 99.64% of de-duplicated)
 524 Database size:        2.39 MB (uncompressed)
 525 (some values do not take into account not-yet-uploaded dirty blocks in cache)
 526 #
 527 </pre></blockquote></p>
 528
 529 <p>I mentioned earlier that there are several possible suppliers of
 530 storage.  I did not try to locate them all, but am aware of at least
 531 <a href="https://www.greenqloud.com/">Greenqloud</a>,
 532 <a href="http://drive.google.com/">Google Drive</a>,
 533 <a href="http://aws.amazon.com/s3/">Amazon S3 web serivces</a>,
 534 <a href="http://www.rackspace.com/">Rackspace</a> and
 535 <a href="http://crowncloud.net/">Crowncloud</A>.  The latter even
 536 accept payment in Bitcoin.  Pick one that suit your need.  Some of
 537 them provide several GiB of free storage, but the prize models are
 538 quite different and you will have to figure out what suits you
 539 best.</p>
 540
 541 <p>While researching this blog post, I had a look at research papers
 542 and posters discussing the S3QL file system.  There are several, which
 543 told me that the file system is getting a critical check by the
 544 science community and increased my confidence in using it.  One nice
 545 poster is titled
 546 "<a href="http://www.lanl.gov/orgs/adtsc/publications/science_highlights_2013/docs/pg68_69.pdf">An
 547 Innovative Parallel Cloud Storage System using OpenStack’s SwiftObject
 548 Store and Transformative Parallel I/O Approach</a>" by Hsing-Bung
 549 Chen, Benjamin McClelland, David Sherrill, Alfred Torrez, Parks Fields
 550 and Pamela Smith.  Please  have a look.</p>
 551
 552 <p>Given my problems with different file systems earlier, I decided to
 553 check out the mounted S3QL file system to see if it would be usable as
 554 a home directory (in other word, that it provided POSIX semantics when
 555 it come to locking and umask handling etc).  Running
 556 <a href="http://people.skolelinux.org/pere/blog/Testing_if_a_file_system_can_be_used_for_home_directories___.html">my
 557 test code to check file system semantics</a>, I was happy to discover that
 558 no error was found.  So the file system can be used for home
 559 directories, if one chooses to do so.</p>
 560
 561 <p>If you do not want a locally file system, and want something that
 562 work without the Linux fuse file system, I would like to mention the
 563 <a href="http://www.tarsnap.com/">Tarsnap service</a>, which also
 564 provide locally encrypted backup using a command line client.  It have
 565 a nicer access control system, where one can split out read and write
 566 access, allowing some systems to write to the backup and others to
 567 only read from it.</p>
 568
 569 <p>As usual, if you use Bitcoin and want to show your support of my
 570 activities, please send Bitcoin donations to my address
 571 <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b&label=PetterReinholdtsenBlog">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
 572 </div>
 573       <div class="tags">
 574
 575
 576         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern</a>, <a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet</a>.
 577
 578
 579       </div>
 580     </div>
 581     <div class="padding"></div>
 582
 583     <div class="entry">
 584       <div class="title"><a href="http://people.skolelinux.org/pere/blog/EU_domstolen_bekreftet_i_dag_at_datalagringsdirektivet_er_ulovlig.html">EU-domstolen bekreftet i dag at datalagringsdirektivet er ulovlig</a></div>
 585       <div class="date"> 8th April 2014</div>
 586       <div class="body"><p>I dag kom endelig avgjørelsen fra EU-domstolen om
 587 datalagringsdirektivet, som ikke overraskende ble dømt ulovlig og i
 588 strid med borgernes grunnleggende rettigheter.  Hvis du lurer på hva
 589 datalagringsdirektivet er for noe, så er det
 590 <a href="http://tv.nrk.no/program/koid75005313/tema-dine-digitale-spor-datalagringsdirektivet">en
 591 flott dokumentar tilgjengelig hos NRK</a> som jeg tidligere
 592 <a href="http://people.skolelinux.org/pere/blog/Dokumentaren_om_Datalagringsdirektivet_sendes_endelig_p__NRK.html">har
 593 anbefalt</a> alle å se.</p>
 594
 595 <p>Her er et liten knippe nyhetsoppslag om saken, og jeg regner med at
 596 det kommer flere ut over dagen.  Flere kan finnes
 597 <a href="http://www.mylder.no/?drill=datalagringsdirektivet&intern=1">via
 598 mylder</a>.</p>
 599
 600 <p><ul>
 601
 602 <li><a href="http://e24.no/digital/eu-domstolen-datalagringsdirektivet-er-ugyldig/22879592">EU-domstolen:
 603 Datalagringsdirektivet er ugyldig</a> - e24.no 2014-04-08
 604
 605 <li><a href="http://www.aftenposten.no/nyheter/iriks/EU-domstolen-Datalagringsdirektivet-er-ulovlig-7529032.html">EU-domstolen:
 606 Datalagringsdirektivet er ulovlig</a> - aftenposten.no 2014-04-08
 607
 608 <li><a href="http://www.aftenposten.no/nyheter/iriks/politikk/Krever-DLD-stopp-i-Norge-7530086.html">Krever
 609 DLD-stopp i Norge</a> - aftenposten.no 2014-04-08
 610
 611 <li><a href="http://www.p4.no/story.aspx?id=566431">Apenes: - En
 612 gledens dag</a> - p4.no 2014-04-08
 613
 614 <li><a href="http://www.nrk.no/norge/_-datalagringsdirektivet-er-ugyldig-1.11655929">EU-domstolen:
 615 – Datalagringsdirektivet er ugyldig</a> - nrk.no 2014-04-08</li>
 616
 617 <li><a href="http://www.vg.no/nyheter/utenriks/data-og-nett/eu-domstolen-datalagringsdirektivet-er-ugyldig/a/10130280/">EU-domstolen:
 618 Datalagringsdirektivet er ugyldig</a> - vg.no 2014-04-08</li>
 619
 620 <li><a href="http://www.dagbladet.no/2014/04/08/nyheter/innenriks/datalagringsdirektivet/personvern/32711646/">-
 621 Vi bør skrote hele datalagringsdirektivet</a> - dagbladet.no
 622 2014-04-08</li>
 623
 624 <li><a href="http://www.digi.no/928137/eu-domstolen-dld-er-ugyldig">EU-domstolen:
 625 DLD er ugyldig</a> - digi.no 2014-04-08</li>
 626
 627 <li><a href="http://www.irishtimes.com/business/sectors/technology/european-court-declares-data-retention-directive-invalid-1.1754150">European
 628 court declares data retention directive invalid</a> - irishtimes.com
 629 2014-04-08</li>
 630
 631 <li><a href="http://www.reuters.com/article/2014/04/08/us-eu-data-ruling-idUSBREA370F020140408?feedType=RSS">EU
 632 court rules against requirement to keep data of telecom users</a> -
 633 reuters.com 2014-04-08</li>
 634
 635 </ul>
 636 </p>
 637
 638 <p>Jeg synes det er veldig fint at nok en stemme slår fast at
 639 totalitær overvåkning av befolkningen er uakseptabelt, men det er
 640 fortsatt like viktig å beskytte privatsfæren som før, da de
 641 teknologiske mulighetene fortsatt finnes og utnyttes, og jeg tror
 642 innsats i prosjekter som
 643 <a href="https://wiki.debian.org/FreedomBox">Freedombox</a> og
 644 <a href="http://www.dugnadsnett.no/">Dugnadsnett</a> er viktigere enn
 645 noen gang.</p>
 646
 647 <p><strong>Update 2014-04-08 12:10</strong>: Kronerullingen for å
 648 stoppe datalagringsdirektivet i Norge gjøres hos foreningen
 649 <a href="http://www.digitaltpersonvern.no/">Digitalt Personvern</a>,
 650 som har samlet inn 843 215,- så langt men trenger nok mye mer hvis
 651
 652 ikke Høyre og Arbeiderpartiet bytter mening i saken.  Det var
 653 <a href="http://www.holderdeord.no/parliament-issues/48650">kun
 654 partinene Høyre og Arbeiderpartiet</a> som stemte for
 655 Datalagringsdirektivet, og en av dem må bytte mening for at det skal
 656 bli flertall mot i Stortinget.  Se mer om saken
 657 <a href="http://www.holderdeord.no/issues/69-innfore-datalagringsdirektivet">Holder
 658 de ord</a>.</p>
 659 </div>
 660       <div class="tags">
 661
 662
 663         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/dld">dld</a>, <a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk</a>, <a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern</a>, <a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet</a>, <a href="http://people.skolelinux.org/pere/blog/tags/surveillance">surveillance</a>.
 664
 665
 666       </div>
 667     </div>
 668     <div class="padding"></div>
 669
 670     <div class="entry">
 671       <div class="title"><a href="http://people.skolelinux.org/pere/blog/ReactOS_Windows_clone___nice_free_software.html">ReactOS Windows clone - nice free software</a></div>
 672       <div class="date"> 1st April 2014</div>
 673       <div class="body"><p>Microsoft have announced that Windows XP reaches its end of life
 674 2014-04-08, in 7 days.  But there are heaps of machines still running
 675 Windows XP, and depending on Windows XP to run their applications, and
 676 upgrading will be expensive, both when it comes to money and when it
 677 comes to the amount of effort needed to migrate from Windows XP to a
 678 new operating system.  Some obvious options (buy new a Windows
 679 machine, buy a MacOSX machine, install Linux on the existing machine)
 680 are already well known and covered elsewhere.  Most of them involve
 681 leaving the user applications installed on Windows XP behind and
 682 trying out replacements or updated versions. In this blog post I want
 683 to mention one strange bird that allow people to keep the hardware and
 684 the existing Windows XP applications and run them on a free software
 685 operating system that is Windows XP compatible.</p>
 686
 687 <p><a href="http://www.reactos.org/">ReactOS</a> is a free software
 688 operating system (GNU GPL licensed) working on providing a operating
 689 system that is binary compatible with Windows, able to run windows
 690 programs directly and to use Windows drivers for hardware directly.
 691 The project goal is for Windows user to keep their existing machines,
 692 drivers and software, and gain the advantages from user a operating
 693 system without usage limitations caused by non-free licensing.  It is
 694 a Windows clone running directly on the hardware, so quite different
 695 from the approach taken by <a href="http://www.winehq.org/">the Wine
 696 project</a>, which make it possible to run Windows binaries on
 697 Linux.</p>
 698
 699 <p>The ReactOS project share code with the Wine project, so most
 700 shared libraries available on Windows are already implemented already.
 701 There is also a software manager like the one we are used to on Linux,
 702 allowing the user to install free software applications with a simple
 703 click directly from the Internet.  Check out the
 704 <a href="http://www.reactos.org/screenshots">screen shots on the
 705 project web site</a> for an idea what it look like (it looks just like
 706 Windows before metro).</p>
 707
 708 <p>I do not use ReactOS myself, preferring Linux and Unix like
 709 operating systems.  I've tested it, and it work fine in a virt-manager
 710 virtual machine.  The browser, minesweeper, notepad etc is working
 711 fine as far as I can tell.  Unfortunately, my main test application
 712 is the software included on a CD with the Lego Mindstorms NXT, which
 713 seem to install just fine from CD but fail to leave any binaries on
 714 the disk after the installation.  So no luck with that test software.
 715 No idea why, but hope someone else figure out and fix the problem.
 716 I've tried the ReactOS Live ISO on a physical machine, and it seemed
 717 to work just fine.  If you like Windows and want to keep running your
 718 old Windows binaries, check it out by
 719 <a href="http://www.reactos.org/download">downloading</a> the
 720 installation CD, the live CD or the preinstalled virtual machine
 721 image.</p>
 722 </div>
 723       <div class="tags">
 724
 725
 726         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/reactos">reactos</a>.
 727
 728
 729       </div>
 730     </div>
 731     <div class="padding"></div>
 732
 733     <div class="entry">
 734       <div class="title"><a href="http://people.skolelinux.org/pere/blog/Debian_Edu_interview__Roger_Marsal.html">Debian Edu interview: Roger Marsal</a></div>
 735       <div class="date">30th March 2014</div>
 736       <div class="body"><p><a href="http://www.skolelinux.org/">Debian Edu / Skolelinux</a>
 737 keep gaining new users.  Some weeks ago, a person showed up on IRC,
 738 <a href="irc://irc.debian.org/#debian-edu">#debian-edu</a>, with a
 739 wish to contribute, and I managed to get a interview with this great
 740 contributor Roger Marsal to learn more about his background.</p>
 741
 742 <p><strong>Who are you, and how do you spend your days?</strong></p>
 743
 744 <p>My name is Roger Marsal, I'm 27 years old (1986 generation) and I
 745 live in Barcelona, Spain. I've got a strong business background and I
 746 work as a patrimony manager and as a real estate agent.  Additionally,
 747 I've co-founded a British based tech company that is nowadays on the
 748 last development phase of a new social networking concept.</p>
 749
 750 <p>I'm a Linux enthusiast that started its journey with Ubuntu four years
 751 ago and have recently switched to Debian seeking rock solid stability
 752 and as a necessary step to gain expertise.</p>
 753
 754 <p>In a nutshell, I spend my days working and learning as much as I
 755 can to face both my job, entrepreneur project and feed my Linux
 756 hunger.</p>
 757
 758 <p><strong>How did you get in contact with the Skolelinux / Debian Edu
 759 project?</strong></p>
 760
 761 <p>I discovered the <a href="http://www.ltsp.org/">LTSP</a> advantages
 762 with "Ubuntu 12.04 alternate install" and after a year of use I
 763 started looking for an alternative.  Even though I highly value and
 764 respect the Ubuntu project, I thought it was necessary for me to
 765 change to a more robust and stable alternative.  As far as I was using
 766 Debian on my personal laptop I thought it would be fine to install
 767 Debian and configure an LTSP server myself.  Surprised, I discovered
 768 that the Debian project also supported a kind of Edubuntu equivalent,
 769 and after having some pain I obtained a Debian Edu network up and
 770 running.  I just loved it.</p>
 771
 772 <p><strong>What do you see as the advantages of Skolelinux / Debian
 773 Edu?</strong></p>
 774
 775 <p>I found a main advantage in that, once you know "the tips and
 776 tricks", a new installation just works out of the box. It's the most
 777 complete alternative I've found to create an LTSP network. All the
 778 other distributions seems to be made of plastic, Debian Edu seems to
 779 be made of steel.</p>
 780
 781 <p><strong>What do you see as the disadvantages of Skolelinux / Debian
 782 Edu?</strong></p>
 783
 784 <p>I found two main disadvantages.</p>
 785
 786 <p>I'm not an expert but I've got notions and I had to spent a considerable
 787 amount of time trying to bring up a standard network topology. I'm quite
 788 stubborn and I just worked until I did but I'm sure many people with few
 789 resources (not big schools, but academies for example) would have switched
 790 or dropped.</p>
 791
 792 <p>It's amazing how such a complex system like Debian Edu has achieved
 793 this out-of-the-box state. Even though tweaking without breaking gets
 794 more difficult, as more factors have to be considered. This can
 795 discourage many people too.</p>
 796
 797 <p><strong>Which free software do you use daily?</strong></p>
 798
 799 <p>I use Debian, Firefox, Okular, Inkscape, LibreOffice and
 800 Virtualbox.</p>
 801
 802
 803 <p><strong>Which strategy do you believe is the right one to use to
 804 get schools to use free software?</strong></p>
 805
 806 <p>I don't think there is a need for a particular strategy. The free
 807 attribute in both "freedom" and "no price" meanings is what will
 808 really bring free software to schools. In my experience I can think of
 809 the <a href="http://www.r-project.org/">"R" statistical language</a>; a
 810 few years a ago was an extremely nerd tool for university people.
 811 Today it's being increasingly used to teach statistics at many
 812 different level of studies.  I believe free and open software will
 813 increasingly gain popularity, but I'm sure schools will be one of the
 814 first scenarios where this will happen.</p>
 815 </div>
 816       <div class="tags">
 817
 818
 819         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/intervju">intervju</a>.
 820
 821
 822       </div>
 823     </div>
 824     <div class="padding"></div>
 825
 826     <div class="entry">
 827       <div class="title"><a href="http://people.skolelinux.org/pere/blog/Dokumentaren_om_Datalagringsdirektivet_sendes_endelig_p__NRK.html">Dokumentaren om Datalagringsdirektivet sendes endelig på NRK</a></div>
 828       <div class="date">26th March 2014</div>
 829       <div class="body"><p><a href="http://www.nuug.no/">Foreningen NUUG</a> melder i natt at
 830 NRK nå har bestemt seg for
 831 <a href="http://www.nuug.no/news/NRK_viser_filmen_om_Datalagringsdirektivet_f_rste_gang_2014_03_31.shtml">når
 832 den norske dokumentarfilmen om datalagringsdirektivet skal
 833 sendes</a> (se <a href="http://www.imdb.com/title/tt2832844/">IMDB</a>
 834 for detaljer om filmen) . Første visning blir på NRK2 mandag
 835 2014-03-31 kl. 19:50, og deretter visninger onsdag 2014-04-02
 836 kl. 12:30, fredag 2014-04-04 kl. 19:40 og søndag 2014-04-06 kl. 15:10.
 837 Jeg har sett dokumentaren, og jeg anbefaler enhver å se den selv.  Som
 838 oppvarming mens vi venter anbefaler jeg Bjørn Stærks kronikk i
 839 Aftenposten fra i går,
 840 <a href="http://www.aftenposten.no/meninger/kronikker/Autoritar-gjokunge-7514915.html">Autoritær
 841 gjøkunge</a>, der han gir en grei skisse av hvor ille det står til med
 842 retten til privatliv og beskyttelsen av demokrati i Norge og resten
 843 verden, og helt riktig slår fast at det er vi i databransjen som
 844 sitter med nøkkelen til å gjøre noe med dette.  Jeg har involvert meg
 845 i prosjektene <a href="http://www.dugnadsnett.no/">dugnadsnett.no</a>
 846 og <a href="https://wiki.debian.org/FreedomBox">FreedomBox</a> for å
 847 forsøke å gjøre litt selv for å bedre situasjonen, men det er mye
 848 hardt arbeid fra mange flere enn meg som gjenstår før vi kan sies å ha
 849 gjenopprettet balansen.</p>
 850
 851 <p>Jeg regner med at nettutgaven dukker opp på
 852 <a href="http://tv.nrk.no/program/koid75005313/tema-dine-digitale-spor-datalagringsdirektivet">NRKs
 853 side om filmen om datalagringsdirektivet</a> om fem dager.  Hold et
 854 øye med siden, og tips venner og slekt om at de også bør se den.</p>
 855 </div>
 856       <div class="tags">
 857
 858
 859         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/dld">dld</a>, <a href="http://people.skolelinux.org/pere/blog/tags/freedombox">freedombox</a>, <a href="http://people.skolelinux.org/pere/blog/tags/mesh network">mesh network</a>, <a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk</a>, <a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern</a>, <a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet</a>, <a href="http://people.skolelinux.org/pere/blog/tags/surveillance">surveillance</a>.
 860
 861
 862       </div>
 863     </div>
 864     <div class="padding"></div>
 865
 866     <div class="entry">
 867       <div class="title"><a href="http://people.skolelinux.org/pere/blog/Public_Trusted_Timestamping_services_for_everyone.html">Public Trusted Timestamping services for everyone</a></div>
 868       <div class="date">25th March 2014</div>
 869       <div class="body"><p>Did you ever need to store logs or other files in a way that would
 870 allow it to be used as evidence in court, and needed a way to
 871 demonstrate without reasonable doubt that the file had not been
 872 changed since it was created?  Or, did you ever need to document that
 873 a given document was received at some point in time, like some
 874 archived document or the answer to an exam, and not changed after it
 875 was received?  The problem in these settings is to remove the need to
 876 trust yourself and your computers, while still being able to prove
 877 that a file is the same as it was at some given time in the past.</p>
 878
 879 <p>A solution to these problems is to have a trusted third party
 880 "stamp" the document and verify that at some given time the document
 881 looked a given way.  Such
 882 <a href="https://en.wikipedia.org/wiki/Notarius">notarius</a> service
 883 have been around for thousands of years, and its digital equivalent is
 884 called a
 885 <a href="http://en.wikipedia.org/wiki/Trusted_timestamping">trusted
 886 timestamping service</a>.  <a href="http://www.ietf.org/">The Internet
 887 Engineering Task Force</a> standardised how such service could work a
 888 few years ago as <a href="http://tools.ietf.org/html/rfc3161">RFC
 889 3161</a>.  The mechanism is simple.  Create a hash of the file in
 890 question, send it to a trusted third party which add a time stamp to
 891 the hash and sign the result with its private key, and send back the
 892 signed hash + timestamp.  Both email, FTP and HTTP can be used to
 893 request such signature, depending on what is provided by the service
 894 used. Anyone with the document and the signature can then verify that
 895 the document matches the signature by creating their own hash and
 896 checking the signature using the trusted third party public key.
 897 There are several commercial services around providing such
 898 timestamping.  A quick search for
 899 "<a href="https://duckduckgo.com/?q=rfc+3161+service">rfc 3161
 900 service</a>" pointed me to at least
 901 <a href="https://www.digistamp.com/technical/how-a-digital-time-stamp-works/">DigiStamp</a>,
 902 <a href="http://www.quovadisglobal.co.uk/CertificateServices/SigningServices/TimeStamp.aspx">Quo
 903 Vadis</a>,
 904 <a href="https://www.globalsign.com/timestamp-service/">Global Sign</a>
 905 and <a href="http://www.globaltrustfinder.com/TSADefault.aspx">Global
 906 Trust Finder</a>.  The system work as long as the private key of the
 907 trusted third party is not compromised.</p>
 908
 909 <p>But as far as I can tell, there are very few public trusted
 910 timestamp services available for everyone.  I've been looking for one
 911 for a while now. But yesterday I found one over at
 912 <a href="https://www.pki.dfn.de/zeitstempeldienst/">Deutches
 913 Forschungsnetz</a> mentioned in
 914 <a href="http://www.d-mueller.de/blog/dealing-with-trusted-timestamps-in-php-rfc-3161/">a
 915 blog by David Müller</a>.  I then found
 916 <a href="http://www.rz.uni-greifswald.de/support/dfn-pki-zertifikate/zeitstempeldienst.html">a
 917 good recipe on how to use the service</a> over at the University of
 918 Greifswald.</p>
 919
 920 <p><a href="http://www.openssl.org/">The OpenSSL library</a> contain
 921 both server and tools to use and set up your own signing service.  See
 922 the ts(1SSL), tsget(1SSL) manual pages for more details.  The
 923 following shell script demonstrate how to extract a signed timestamp
 924 for any file on the disk in a Debian environment:</p>
 925
 926 <p><blockquote><pre>
 927 #!/bin/sh
 928 set -e
 929 url="http://zeitstempel.dfn.de"
 930 caurl="https://pki.pca.dfn.de/global-services-ca/pub/cacert/chain.txt"
 931 reqfile=$(mktemp -t tmp.XXXXXXXXXX.tsq)
 932 resfile=$(mktemp -t tmp.XXXXXXXXXX.tsr)
 933 cafile=chain.txt
 934 if [ ! -f $cafile ] ; then
 935     wget -O $cafile "$caurl"
 936 fi
 937 openssl ts -query -data "$1" -cert | tee "$reqfile" \
 938     | /usr/lib/ssl/misc/tsget -h "$url" -o "$resfile"
 939 openssl ts -reply -in "$resfile" -text 1>&2
 940 openssl ts -verify -data "$1" -in "$resfile" -CAfile "$cafile" 1>&2
 941 base64 < "$resfile"
 942 rm "$reqfile" "$resfile"
 943 </pre></blockquote></p>
 944
 945 <p>The argument to the script is the file to timestamp, and the output
 946 is a base64 encoded version of the signature to STDOUT and details
 947 about the signature to STDERR.  Note that due to
 948 <a href="http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=742553">a bug
 949 in the tsget script</a>, you might need to modify the included script
 950 and remove the last line.  Or just write your own HTTP uploader using
 951 curl. :) Now you too can prove and verify that files have not been
 952 changed.</p>
 953
 954 <p>But the Internet need more public trusted timestamp services.
 955 Perhaps something for <a href="http://www.uninett.no/">Uninett</a> or
 956 my work place the <a href="http://www.uio.no/">University of Oslo</a>
 957 to set up?</p>
 958 </div>
 959       <div class="tags">
 960
 961
 962         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet</a>.
 963
 964
 965       </div>
 966     </div>
 967     <div class="padding"></div>
 968
 969     <div class="entry">
 970       <div class="title"><a href="http://people.skolelinux.org/pere/blog/Video_DVD_reader_library___python_dvdvideo___nice_free_software.html">Video DVD reader library / python-dvdvideo - nice free software</a></div>
 971       <div class="date">21st March 2014</div>
 972       <div class="body"><p>Keeping your DVD collection safe from scratches and curious
 973 children fingers while still having it available when you want to see a
 974 movie is not straight forward.  My preferred method at the moment is
 975 to store a full copy of the ISO on a hard drive, and use VLC, Popcorn
 976 Hour or other useful players to view the resulting file.  This way the
 977 subtitles and bonus material are still available and using the ISO is
 978 just like inserting the original DVD record in the DVD player.</p>
 979
 980 <p>Earlier I used dd for taking security copies, but it do not handle
 981 DVDs giving read errors (which are quite a few of them).  I've also
 982 tried using
 983 <a href="http://people.skolelinux.org/pere/blog/Ripping_problematic_DVDs_using_dvdbackup_and_genisoimage.html">dvdbackup
 984 and genisoimage</a>, but these days I use the marvellous python library
 985 and program
 986 <a href="http://bblank.thinkmo.de/blog/new-software-python-dvdvideo">python-dvdvideo</a>
 987 written by Bastian Blank.  It is
 988 <a href="http://packages.qa.debian.org/p/python-dvdvideo.html">in Debian
 989 already</a> and the binary package name is python3-dvdvideo. Instead
 990 of trying to read every block from the DVD, it parses the file
 991 structure and figure out which block on the DVD is actually in used,
 992 and only read those blocks from the DVD.  This work surprisingly well,
 993 and I have been able to almost backup my entire DVD collection using
 994 this method.</p>
 995
 996 <p>So far, python-dvdvideo have failed on between 10 and
 997 20 DVDs, which is a small fraction of my collection.  The most common
 998 problem is
 999 <a href="https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=720831">DVDs
1000 using UTF-16 instead of UTF-8 characters</a>, which according to
1001 Bastian is against the DVD specification (and seem to cause some
1002 players to fail too).  A rarer problem is what seem to be inconsistent
1003 DVD structures, as the python library
1004 <a href="https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=723079">claim
1005 there is a overlap between objects</a>.  An equally rare problem claim
1006 <a href="https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=741878">some
1007 value is out of range</a>.  No idea what is going on there.  I wish I
1008 knew enough about the DVD format to fix these, to ensure my movie
1009 collection will stay with me in the future.</p>
1010
1011 <p>So, if you need to keep your DVDs safe, back them up using
1012 python-dvdvideo. :)</p>
1013 </div>
1014       <div class="tags">
1015
1016
1017         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/multimedia">multimedia</a>, <a href="http://people.skolelinux.org/pere/blog/tags/opphavsrett">opphavsrett</a>, <a href="http://people.skolelinux.org/pere/blog/tags/video">video</a>.
1018
1019
1020       </div>
1021     </div>
1022     <div class="padding"></div>
1023
1024     <p style="text-align: right;"><a href="index.rss"><img src="http://people.skolelinux.org/pere/blog/xml.gif" alt="RSS feed" width="36" height="14" /></a></p>
1025     <div id="sidebar">
1026
1027
1028
1029 <h2>Archive</h2>
1030 <ul>
1031
1032 <li>2014
1033 <ul>
1034
1035 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/01/">January (2)</a></li>
1036
1037 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/02/">February (3)</a></li>
1038
1039 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/03/">March (8)</a></li>
1040
1041 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/04/">April (6)</a></li>
1042
1043 </ul></li>
1044
1045 <li>2013
1046 <ul>
1047
1048 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/01/">January (11)</a></li>
1049
1050 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/02/">February (9)</a></li>
1051
1052 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/03/">March (9)</a></li>
1053
1054 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/04/">April (6)</a></li>
1055
1056 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/05/">May (9)</a></li>
1057
1058 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/06/">June (10)</a></li>
1059
1060 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/07/">July (7)</a></li>
1061
1062 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/08/">August (3)</a></li>
1063
1064 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/09/">September (5)</a></li>
1065
1066 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/10/">October (7)</a></li>
1067
1068 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/11/">November (9)</a></li>
1069
1070 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/12/">December (3)</a></li>
1071
1072 </ul></li>
1073
1074 <li>2012
1075 <ul>
1076
1077 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/01/">January (7)</a></li>
1078
1079 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/02/">February (10)</a></li>
1080
1081 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/03/">March (17)</a></li>
1082
1083 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/04/">April (12)</a></li>
1084
1085 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/05/">May (12)</a></li>
1086
1087 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/06/">June (20)</a></li>
1088
1089 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/07/">July (17)</a></li>
1090
1091 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/08/">August (6)</a></li>
1092
1093 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/09/">September (9)</a></li>
1094
1095 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/10/">October (17)</a></li>
1096
1097 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/11/">November (10)</a></li>
1098
1099 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/12/">December (7)</a></li>
1100
1101 </ul></li>
1102
1103 <li>2011
1104 <ul>
1105
1106 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/01/">January (16)</a></li>
1107
1108 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/02/">February (6)</a></li>
1109
1110 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/03/">March (6)</a></li>
1111
1112 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/04/">April (7)</a></li>
1113
1114 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/05/">May (3)</a></li>
1115
1116 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/06/">June (2)</a></li>
1117
1118 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/07/">July (7)</a></li>
1119
1120 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/08/">August (6)</a></li>
1121
1122 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/09/">September (4)</a></li>
1123
1124 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/10/">October (2)</a></li>
1125
1126 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/11/">November (3)</a></li>
1127
1128 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/12/">December (1)</a></li>
1129
1130 </ul></li>
1131
1132 <li>2010
1133 <ul>
1134
1135 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/01/">January (2)</a></li>
1136
1137 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/02/">February (1)</a></li>
1138
1139 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/03/">March (3)</a></li>
1140
1141 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/04/">April (3)</a></li>
1142
1143 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/05/">May (9)</a></li>
1144
1145 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/06/">June (14)</a></li>
1146
1147 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/07/">July (12)</a></li>
1148
1149 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/08/">August (13)</a></li>
1150
1151 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/09/">September (7)</a></li>
1152
1153 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/10/">October (9)</a></li>
1154
1155 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/11/">November (13)</a></li>
1156
1157 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/12/">December (12)</a></li>
1158
1159 </ul></li>
1160
1161 <li>2009
1162 <ul>
1163
1164 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/01/">January (8)</a></li>
1165
1166 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/02/">February (8)</a></li>
1167
1168 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/03/">March (12)</a></li>
1169
1170 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/04/">April (10)</a></li>
1171
1172 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/05/">May (9)</a></li>
1173
1174 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/06/">June (3)</a></li>
1175
1176 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/07/">July (4)</a></li>
1177
1178 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/08/">August (3)</a></li>
1179
1180 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/09/">September (1)</a></li>
1181
1182 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/10/">October (2)</a></li>
1183
1184 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/11/">November (3)</a></li>
1185
1186 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/12/">December (3)</a></li>
1187
1188 </ul></li>
1189
1190 <li>2008
1191 <ul>
1192
1193 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/11/">November (5)</a></li>
1194
1195 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/12/">December (7)</a></li>
1196
1197 </ul></li>
1198
1199 </ul>
1200
1201
1202
1203 <h2>Tags</h2>
1204 <ul>
1205
1206  <li><a href="http://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer (13)</a></li>
1207
1208  <li><a href="http://people.skolelinux.org/pere/blog/tags/amiga">amiga (1)</a></li>
1209
1210  <li><a href="http://people.skolelinux.org/pere/blog/tags/aros">aros (1)</a></li>
1211
1212  <li><a href="http://people.skolelinux.org/pere/blog/tags/bankid">bankid (4)</a></li>
1213
1214  <li><a href="http://people.skolelinux.org/pere/blog/tags/bitcoin">bitcoin (8)</a></li>
1215
1216  <li><a href="http://people.skolelinux.org/pere/blog/tags/bootsystem">bootsystem (14)</a></li>
1217
1218  <li><a href="http://people.skolelinux.org/pere/blog/tags/bsa">bsa (2)</a></li>
1219
1220  <li><a href="http://people.skolelinux.org/pere/blog/tags/chrpath">chrpath (2)</a></li>
1221
1222  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian">debian (98)</a></li>
1223
1224  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu (146)</a></li>
1225
1226  <li><a href="http://people.skolelinux.org/pere/blog/tags/digistan">digistan (10)</a></li>
1227
1228  <li><a href="http://people.skolelinux.org/pere/blog/tags/dld">dld (15)</a></li>
1229
1230  <li><a href="http://people.skolelinux.org/pere/blog/tags/docbook">docbook (10)</a></li>
1231
1232  <li><a href="http://people.skolelinux.org/pere/blog/tags/drivstoffpriser">drivstoffpriser (4)</a></li>
1233
1234  <li><a href="http://people.skolelinux.org/pere/blog/tags/english">english (245)</a></li>
1235
1236  <li><a href="http://people.skolelinux.org/pere/blog/tags/fiksgatami">fiksgatami (21)</a></li>
1237
1238  <li><a href="http://people.skolelinux.org/pere/blog/tags/fildeling">fildeling (12)</a></li>
1239
1240  <li><a href="http://people.skolelinux.org/pere/blog/tags/freeculture">freeculture (12)</a></li>
1241
1242  <li><a href="http://people.skolelinux.org/pere/blog/tags/freedombox">freedombox (8)</a></li>
1243
1244  <li><a href="http://people.skolelinux.org/pere/blog/tags/frikanalen">frikanalen (11)</a></li>
1245
1246  <li><a href="http://people.skolelinux.org/pere/blog/tags/intervju">intervju (40)</a></li>
1247
1248  <li><a href="http://people.skolelinux.org/pere/blog/tags/isenkram">isenkram (8)</a></li>
1249
1250  <li><a href="http://people.skolelinux.org/pere/blog/tags/kart">kart (18)</a></li>
1251
1252  <li><a href="http://people.skolelinux.org/pere/blog/tags/ldap">ldap (9)</a></li>
1253
1254  <li><a href="http://people.skolelinux.org/pere/blog/tags/lenker">lenker (7)</a></li>
1255
1256  <li><a href="http://people.skolelinux.org/pere/blog/tags/ltsp">ltsp (1)</a></li>
1257
1258  <li><a href="http://people.skolelinux.org/pere/blog/tags/mesh network">mesh network (8)</a></li>
1259
1260  <li><a href="http://people.skolelinux.org/pere/blog/tags/multimedia">multimedia (26)</a></li>
1261
1262  <li><a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk (245)</a></li>
1263
1264  <li><a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug (162)</a></li>
1265
1266  <li><a href="http://people.skolelinux.org/pere/blog/tags/offentlig innsyn">offentlig innsyn (11)</a></li>
1267
1268  <li><a href="http://people.skolelinux.org/pere/blog/tags/open311">open311 (2)</a></li>
1269
1270  <li><a href="http://people.skolelinux.org/pere/blog/tags/opphavsrett">opphavsrett (46)</a></li>
1271
1272  <li><a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern (72)</a></li>
1273
1274  <li><a href="http://people.skolelinux.org/pere/blog/tags/raid">raid (1)</a></li>
1275
1276  <li><a href="http://people.skolelinux.org/pere/blog/tags/reactos">reactos (1)</a></li>
1277
1278  <li><a href="http://people.skolelinux.org/pere/blog/tags/reprap">reprap (11)</a></li>
1279
1280  <li><a href="http://people.skolelinux.org/pere/blog/tags/rfid">rfid (2)</a></li>
1281
1282  <li><a href="http://people.skolelinux.org/pere/blog/tags/robot">robot (9)</a></li>
1283
1284  <li><a href="http://people.skolelinux.org/pere/blog/tags/rss">rss (1)</a></li>
1285
1286  <li><a href="http://people.skolelinux.org/pere/blog/tags/ruter">ruter (4)</a></li>
1287
1288  <li><a href="http://people.skolelinux.org/pere/blog/tags/scraperwiki">scraperwiki (2)</a></li>
1289
1290  <li><a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet (40)</a></li>
1291
1292  <li><a href="http://people.skolelinux.org/pere/blog/tags/sitesummary">sitesummary (4)</a></li>
1293
1294  <li><a href="http://people.skolelinux.org/pere/blog/tags/skepsis">skepsis (4)</a></li>
1295
1296  <li><a href="http://people.skolelinux.org/pere/blog/tags/standard">standard (44)</a></li>
1297
1298  <li><a href="http://people.skolelinux.org/pere/blog/tags/stavekontroll">stavekontroll (3)</a></li>
1299
1300  <li><a href="http://people.skolelinux.org/pere/blog/tags/stortinget">stortinget (9)</a></li>
1301
1302  <li><a href="http://people.skolelinux.org/pere/blog/tags/surveillance">surveillance (25)</a></li>
1303
1304  <li><a href="http://people.skolelinux.org/pere/blog/tags/sysadmin">sysadmin (1)</a></li>
1305
1306  <li><a href="http://people.skolelinux.org/pere/blog/tags/valg">valg (8)</a></li>
1307
1308  <li><a href="http://people.skolelinux.org/pere/blog/tags/video">video (40)</a></li>
1309
1310  <li><a href="http://people.skolelinux.org/pere/blog/tags/vitenskap">vitenskap (4)</a></li>
1311
1312  <li><a href="http://people.skolelinux.org/pere/blog/tags/web">web (30)</a></li>
1313
1314 </ul>
1315
1316
1317     </div>
1318     <p style="text-align: right">
1319  Created by <a href="http://steve.org.uk/Software/chronicle">Chronicle v4.6</a>
1320 </p>
1321
1322   </body>
1323 </html>