X-Git-Url: http://pere.pagekite.me/gitweb/homepage.git/blobdiff_plain/eb2bfefa8ba4f868fc150d096326f1a2cf74be5e..a8af0c8c20892a59d5ef8682dde4127e381b874a:/blog/index.rss diff --git a/blog/index.rss b/blog/index.rss index 99889b93e2..085c7f3828 100644 --- a/blog/index.rss +++ b/blog/index.rss @@ -7,770 +7,502 @@ - Some notes on fault tolerant storage systems - http://people.skolelinux.org/pere/blog/Some_notes_on_fault_tolerant_storage_systems.html - http://people.skolelinux.org/pere/blog/Some_notes_on_fault_tolerant_storage_systems.html - Wed, 1 Nov 2017 15:35:00 +0100 - <p>If you care about how fault tolerant your storage is, you might -find these articles and papers interesting. They have formed how I -think of when designing a storage system.</p> - -<ul> - -<li>USENIX :login; <a -href="https://www.usenix.org/publications/login/summer2017/ganesan">Redundancy -Does Not Imply Fault Tolerance. Analysis of Distributed Storage -Reactions to Single Errors and Corruptions</a> by Aishwarya Ganesan, -Ramnatthan Alagappan, Andrea C. Arpaci-Dusseau, and Remzi -H. Arpaci-Dusseau</li> - -<li>ZDNet -<a href="http://www.zdnet.com/article/why-raid-5-stops-working-in-2009/">Why -RAID 5 stops working in 2009</a> by Robin Harris</li> - -<li>ZDNet -<a href="http://www.zdnet.com/article/why-raid-6-stops-working-in-2019/">Why -RAID 6 stops working in 2019</a> by Robin Harris</li> - -<li>USENIX FAST'07 -<a href="http://research.google.com/archive/disk_failures.pdf">Failure -Trends in a Large Disk Drive Population</a> by Eduardo Pinheiro, -Wolf-Dietrich Weber and Luiz André Barroso</li> - -<li>USENIX ;login: <a -href="https://www.usenix.org/system/files/login/articles/hughes12-04.pdf">Data -Integrity. Finding Truth in a World of Guesses and Lies</a> by Doug -Hughes</li> - -<li>USENIX FAST'08 -<a href="https://www.usenix.org/events/fast08/tech/full_papers/bairavasundaram/bairavasundaram_html/">An -cAnalysis of Data Corruption in the Storage Stack</a> - -L. N. Bairavasundaram, G. R. Goodson, B. Schroeder, A. C. -Arpaci-Dusseau, and R. H. Arpaci-Dusseau</li> - -<li>USENIX FAST'07 <a -href="https://www.usenix.org/legacy/events/fast07/tech/schroeder/schroeder_html/">Disk -failures in the real world: what does an MTTF of 1,000,000 hours mean -to you?</a> by B. Schroeder and G. A. Gibson.</li> - -<li>USENIX ;login: <a -href="https://www.usenix.org/events/fast08/tech/full_papers/jiang/jiang_html/">Are -Disks the Dominant Contributor for Storage Failures? A Comprehensive -Study of Storage Subsystem Failure Characteristics</a> by Weihang -Jiang, Chongfeng Hu, Yuanyuan Zhou, and Arkady Kanevsky</li> - -<li>SIGMETRICS 2007 -<a href="http://research.cs.wisc.edu/adsl/Publications/latent-sigmetrics07.pdf">An -analysis of latent sector errors in disk drives</a> - -L. N. Bairavasundaram, G. R. Goodson, S. Pasupathy, and J. Schindler</li> - -</ul> - -<p>Several of these research papers are based on data collected from -hundred thousands or millions of disk, and their findings are eye -opening. The short story is simply do not implicitly trust RAID or -redundant storage systems. Details matter. And unfortunately there -are few options on Linux addressing all the identified issues. Both -ZFS and Btrfs are doing a fairly good job, but have legal and -practical issues on their own. I wonder how cluster file systems like -Ceph do in this regard. After, all the old saying, you know you have -a distributed system when the crash of a compyter you have never heard -of stops you from getting any work done. The same holds true if fault -tolerance do not work.</p> - -<p>Just remember, in the end, it do not matter how redundant, or how -fault tolerant your storage is, if you do not continuously monitor its -status to detect and replace failed disks.</p> + CasparCG Server for TV broadcast playout in Debian + http://people.skolelinux.org/pere/blog/CasparCG_Server_for_TV_broadcast_playout_in_Debian.html + http://people.skolelinux.org/pere/blog/CasparCG_Server_for_TV_broadcast_playout_in_Debian.html + Tue, 15 Jan 2019 00:10:00 +0100 + <p>The layered video playout server created by Sveriges Television, +<a href="https://casparcg.com/">CasparCG Server</a>, entered Debian +today. This completes many months of work to get the source ready to +go into Debian. The first upload to the Debian NEW queue happened a +month ago, but the work upstream to prepare it for Debian started more +than two and a half month ago. So far +<a href="https://tracker.debian.org/pkg/casparcg-server">the +casparcg-server package</a> is only available for amd64, but I hope +this can be improved. The package is in contrib because it depend on +the <a href="https://tracker.debian.org/pkg/fdk-aac">non-free fdk-aac +library</a>. The Debian package lack support for streaming web pages +because Debian is missing CEF, Chromium Embedded Framework. CEF is +wanted by several packages in Debian. But because the Chromium source +is <a href="https://bugs.debian.org/893448">not available as a build +dependency</a>, it is not yet possible to upload CEF to Debian. I +hope this will change in the future.</p> + +<p>The reason I got involved is that +<a href="https://frikanalen.no/">the Norwegian open channel +Frikanalen</a> is starting to use CasparCG for our HD playout, and I +would like to have all the free software tools we use to run the TV +channel available as packages from the Debian project. The last +remaining piece in the puzzle is Open Broadcast Encoder, but it depend +on quite a lot of patched libraries which would have to be included in +Debian first.</p> - Web services for writing academic LaTeX papers as a team - http://people.skolelinux.org/pere/blog/Web_services_for_writing_academic_LaTeX_papers_as_a_team.html - http://people.skolelinux.org/pere/blog/Web_services_for_writing_academic_LaTeX_papers_as_a_team.html - Tue, 31 Oct 2017 21:00:00 +0100 - <p>I was surprised today to learn that a friend in academia did not -know there are easily available web services available for writing -LaTeX documents as a team. I thought it was common knowledge, but to -make sure at least my readers are aware of it, I would like to mention -these useful services for writing LaTeX documents. Some of them even -provide a WYSIWYG editor to ease writing even further.</p> - -<p>There are two commercial services available, -<a href="https://sharelatex.com">ShareLaTeX</a> and -<a href="https://overleaf.com">Overleaf</a>. They are very easy to -use. Just start a new document, select which publisher to write for -(ie which LaTeX style to use), and start writing. Note, these two -have announced their intention to join forces, so soon it will only be -one joint service. I've used both for different documents, and they -work just fine. While -<a href="https://github.com/sharelatex/sharelatex">ShareLaTeX is free -software</a>, while the latter is not. According to <a -href="https://www.overleaf.com/help/17-is-overleaf-open-source">a -announcement from Overleaf</a>, they plan to keep the ShareLaTeX code -base maintained as free software.</p> - -But these two are not the only alternatives. -<a href="https://app.fiduswriter.org/">Fidus Writer</a> is another free -software solution with <a href="https://github.com/fiduswriter">the -source available on github</a>. I have not used it myself. Several -others can be found on the nice -<a href="https://alternativeto.net/software/sharelatex/">alterntiveTo -web service</a>. - -<p>If you like Google Docs or Etherpad, but would like to write -documents in LaTeX, you should check out these services. You can even -host your own, if you want to. :)</p> - + Learn to program with Minetest on Debian + http://people.skolelinux.org/pere/blog/Learn_to_program_with_Minetest_on_Debian.html + http://people.skolelinux.org/pere/blog/Learn_to_program_with_Minetest_on_Debian.html + Sat, 15 Dec 2018 15:30:00 +0100 + <p>A fun way to learn how to program +<a href="https://www.python.org/">Python</a> is to follow the +instructions in the book +"<a href="https://nostarch.com/programwithminecraft">Learn to program +with Minecraft</a>", which introduces programming in Python to people +who like to play with Minecraft. The book uses a Python library to +talk to a TCP/IP socket with an API accepting build instructions and +providing information about the current players in a Minecraft world. +The TCP/IP API was first created for the Minecraft implementation for +Raspberry Pi, and has since been ported to some server versions of +Minecraft. The book contain recipes for those using Windows, MacOSX +and Raspian. But a little known fact is that you can follow the same +recipes using the free software construction game +<a href="https://minetest.net/">Minetest</a>.</p> + +<p>There is <a href="https://github.com/sprintingkiwi/pycraft_mod">a +Minetest module implementing the same API</a>, making it possible to +use the Python programs coded to talk to Minecraft with Minetest too. +I +<a href="https://ftp-master.debian.org/new/minetest-mod-pycraft_0.20%2Bgit20180331.0376a0a%2Bdfsg-1.html">uploaded +this module</a> to Debian two weeks ago, and as soon as it clears the +FTP masters NEW queue, learning to program Python with Minetest on +Debian will be a simple 'apt install' away. The Debian package is +maintained as part of the Debian Games team, and +<a href="https://salsa.debian.org/games-team/unfinished/minetest-mod-pycraft">the +packaging rules</a> are currently located under 'unfinished' on +Salsa.</p> + +<p>You will most likely need to install several of the Minetest +modules in Debian for the examples included with the library to work +well, as there are several blocks used by the example scripts that are +provided via modules in Minetest. Without the required blocks, a +simple stone block is used instead. My initial testing with a analog +clock did not get gold arms as instructed in the python library, but +instead used stone arms.</p> + +<p>I tried to find a way to add the API to the desktop version of +Minecraft, but were unable to find any working recipes. The +<a href="https://www.epiphanydigest.com/tag/minecraft-python-api/">recipes</a> +I <a href="https://github.com/kbsriram/mcpiapi">found</a> are only +working with a standalone Minecraft server setup. Are there any +options to use with the normal desktop version?</p> + +<p>As usual, if you use Bitcoin and want to show your support of my +activities, please send Bitcoin donations to my address +<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p> - Locating IMDB IDs of movies in the Internet Archive using Wikidata - http://people.skolelinux.org/pere/blog/Locating_IMDB_IDs_of_movies_in_the_Internet_Archive_using_Wikidata.html - http://people.skolelinux.org/pere/blog/Locating_IMDB_IDs_of_movies_in_the_Internet_Archive_using_Wikidata.html - Wed, 25 Oct 2017 12:20:00 +0200 - <p>Recently, I needed to automatically check the copyright status of a -set of <a href="http://www.imdb.com/">The Internet Movie database -(IMDB)</a> entries, to figure out which one of the movies they refer -to can be freely distributed on the Internet. This proved to be -harder than it sounds. IMDB for sure list movies without any -copyright protection, where the copyright protection has expired or -where the movie is lisenced using a permissive license like one from -Creative Commons. These are mixed with copyright protected movies, -and there seem to be no way to separate these classes of movies using -the information in IMDB.</p> - -<p>First I tried to look up entries manually in IMDB, -<a href="https://www.wikipedia.org/">Wikipedia</a> and -<a href="https://www.archive.org/">The Internet Archive</a>, to get a -feel how to do this. It is hard to know for sure using these sources, -but it should be possible to be reasonable confident a movie is "out -of copyright" with a few hours work per movie. As I needed to check -almost 20,000 entries, this approach was not sustainable. I simply -can not work around the clock for about 6 years to check this data -set.</p> - -<p>I asked the people behind The Internet Archive if they could -introduce a new metadata field in their metadata XML for IMDB ID, but -was told that they leave it completely to the uploaders to update the -metadata. Some of the metadata entries had IMDB links in the -description, but I found no way to download all metadata files in bulk -to locate those ones and put that approach aside.</p> - -<p>In the process I noticed several Wikipedia articles about movies -had links to both IMDB and The Internet Archive, and it occured to me -that I could use the Wikipedia RDF data set to locate entries with -both, to at least get a lower bound on the number of movies on The -Internet Archive with a IMDB ID. This is useful based on the -assumption that movies distributed by The Internet Archive can be -legally distributed on the Internet. With some help from the RDF -community (thank you DanC), I was able to come up with this query to -pass to <a href="https://query.wikidata.org/">the SPARQL interface on -Wikidata</a>: + Non-blocking bittorrent plugin for vlc + http://people.skolelinux.org/pere/blog/Non_blocking_bittorrent_plugin_for_vlc.html + http://people.skolelinux.org/pere/blog/Non_blocking_bittorrent_plugin_for_vlc.html + Wed, 12 Dec 2018 07:20:00 +0100 + <p>A few hours ago, a new and improved version (2.4) of +<a href="https://tracker.debian.org/pkg/vlc-plugin-bittorrent">the VLC +bittorrent plugin</a> was uploaded to Debian. This new version +include a complete rewrite of the bittorrent related code, which seem +to make the plugin non-blocking. This mean you can actually exit VLC +even when the plugin seem to be unable to get the bittorrent streaming +started. The new version also include support for filtering playlist +by file extension using command line options, if you want to avoid +processing audio, video or images. The package is currently in Debian +unstable, but should be available in Debian testing in two days. To +test it, simply install it like this:</p> <p><pre> -SELECT ?work ?imdb ?ia ?when ?label -WHERE -{ - ?work wdt:P31/wdt:P279* wd:Q11424. - ?work wdt:P345 ?imdb. - ?work wdt:P724 ?ia. - OPTIONAL { - ?work wdt:P577 ?when. - ?work rdfs:label ?label. - FILTER(LANG(?label) = "en"). - } -} +apt install vlc-plugin-bittorrent </pre></p> -<p>If I understand the query right, for every film entry anywhere in -Wikpedia, it will return the IMDB ID and The Internet Archive ID, and -when the movie was released and its English title, if either or both -of the latter two are available. At the moment the result set contain -2338 entries. Of course, it depend on volunteers including both -correct IMDB and The Internet Archive IDs in the wikipedia articles -for the movie. It should be noted that the result will include -duplicates if the movie have entries in several languages. There are -some bogus entries, either because The Internet Archive ID contain a -typo or because the movie is not available from The Internet Archive. -I did not verify the IMDB IDs, as I am unsure how to do that -automatically.</p> - -<p>I wrote a small python script to extract the data set from Wikidata -and check if the XML metadata for the movie is available from The -Internet Archive, and after around 1.5 hour it produced a list of 2097 -free movies and their IMDB ID. In total, 171 entries in Wikidata lack -the refered Internet Archive entry. I assume the 70 "disappearing" -entries (ie 2338-2097-171) are duplicate entries.</p> - -<p>This is not too bad, given that The Internet Archive report to -contain <a href="https://archive.org/details/feature_films">5331 -feature films</a> at the moment, but it also mean more than 3000 -movies are missing on Wikipedia or are missing the pair of references -on Wikipedia.</p> - -<p>I was curious about the distribution by release year, and made a -little graph to show how the amount of free movies is spread over the -years:<p> - -<p><img src="http://people.skolelinux.org/pere/blog/images/2017-10-25-verk-i-det-fri-filmer.png"></p> - -<p>I expect the relative distribution of the remaining 3000 movies to -be similar.</p> - -<p>If you want to help, and want to ensure Wikipedia can be used to -cross reference The Internet Archive and The Internet Movie Database, -please make sure entries like this are listed under the "External -links" heading on the Wikipedia article for the movie:</p> +<p>After it is installed, you can try to use it to play a file +downloaded live via bittorrent like this: <p><pre> -* {{Internet Archive film|id=FightingLady}} -* {{IMDb title|id=0036823|title=The Fighting Lady}} +vlc https://archive.org/download/Glass_201703/Glass_201703_archive.torrent </pre></p> -<p>Please verify the links on the final page, to make sure you did not -introduce a typo.</p> - -<p>Here is the complete list, if you want to correct the 171 -identified Wikipedia entries with broken links to The Internet -Archive: <a href="http://www.wikidata.org/entity/Q1140317">Q1140317</a>, -<a href="http://www.wikidata.org/entity/Q458656">Q458656</a>, -<a href="http://www.wikidata.org/entity/Q458656">Q458656</a>, -<a href="http://www.wikidata.org/entity/Q470560">Q470560</a>, -<a href="http://www.wikidata.org/entity/Q743340">Q743340</a>, -<a href="http://www.wikidata.org/entity/Q822580">Q822580</a>, -<a href="http://www.wikidata.org/entity/Q480696">Q480696</a>, -<a href="http://www.wikidata.org/entity/Q128761">Q128761</a>, -<a href="http://www.wikidata.org/entity/Q1307059">Q1307059</a>, -<a href="http://www.wikidata.org/entity/Q1335091">Q1335091</a>, -<a href="http://www.wikidata.org/entity/Q1537166">Q1537166</a>, -<a href="http://www.wikidata.org/entity/Q1438334">Q1438334</a>, -<a href="http://www.wikidata.org/entity/Q1479751">Q1479751</a>, -<a href="http://www.wikidata.org/entity/Q1497200">Q1497200</a>, -<a href="http://www.wikidata.org/entity/Q1498122">Q1498122</a>, -<a href="http://www.wikidata.org/entity/Q865973">Q865973</a>, -<a href="http://www.wikidata.org/entity/Q834269">Q834269</a>, -<a href="http://www.wikidata.org/entity/Q841781">Q841781</a>, -<a href="http://www.wikidata.org/entity/Q841781">Q841781</a>, -<a href="http://www.wikidata.org/entity/Q1548193">Q1548193</a>, -<a href="http://www.wikidata.org/entity/Q499031">Q499031</a>, -<a href="http://www.wikidata.org/entity/Q1564769">Q1564769</a>, -<a 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href="http://www.wikidata.org/entity/Q7783704">Q7783704</a>, -<a href="http://www.wikidata.org/entity/Q7857590">Q7857590</a>, -<a href="http://www.wikidata.org/entity/Q3372526">Q3372526</a>, -<a href="http://www.wikidata.org/entity/Q3372642">Q3372642</a>, -<a href="http://www.wikidata.org/entity/Q3372816">Q3372816</a>, -<a href="http://www.wikidata.org/entity/Q3372909">Q3372909</a>, -<a href="http://www.wikidata.org/entity/Q7959649">Q7959649</a>, -<a href="http://www.wikidata.org/entity/Q7977485">Q7977485</a>, -<a href="http://www.wikidata.org/entity/Q7992684">Q7992684</a>, -<a href="http://www.wikidata.org/entity/Q3817966">Q3817966</a>, -<a href="http://www.wikidata.org/entity/Q3821852">Q3821852</a>, -<a href="http://www.wikidata.org/entity/Q3420907">Q3420907</a>, -<a href="http://www.wikidata.org/entity/Q3429733">Q3429733</a>, -<a href="http://www.wikidata.org/entity/Q774474">Q774474</a></p> +<p>As usual, if you use Bitcoin and want to show your support of my +activities, please send Bitcoin donations to my address +<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p> - A one-way wall on the border? - http://people.skolelinux.org/pere/blog/A_one_way_wall_on_the_border_.html - http://people.skolelinux.org/pere/blog/A_one_way_wall_on_the_border_.html - Sat, 14 Oct 2017 22:10:00 +0200 - <p>I find it fascinating how many of the people being locked inside -the proposed border wall between USA and Mexico support the idea. The -proposal to keep Mexicans out reminds me of -<a href="http://www.history.com/news/10-things-you-may-not-know-about-the-berlin-wall">the -propaganda twist from the East Germany government</a> calling the wall -the “Antifascist Bulwark” after erecting the Berlin Wall, claiming -that the wall was erected to keep enemies from creeping into East -Germany, while it was obvious to the people locked inside it that it -was erected to keep the people from escaping.</p> - -<p>Do the people in USA supporting this wall really believe it is a -one way wall, only keeping people on the outside from getting in, -while not keeping people in the inside from getting out?</p> + Retten til kontant betaling er en rettighet som må brukes for å beholdes + http://people.skolelinux.org/pere/blog/Retten_til_kontant_betaling_er_en_rettighet_som_m__brukes_for___beholdes.html + http://people.skolelinux.org/pere/blog/Retten_til_kontant_betaling_er_en_rettighet_som_m__brukes_for___beholdes.html + Tue, 11 Dec 2018 10:00:00 +0100 + <p><a href="https://www.fn.no/Om-FN/Avtaler/Menneskerettigheter/FNs-verdenserklaering-om-menneskerettigheter">FNs +menneskerettighetserklæring</a> artikkel 13 første punkt lyder som +følger:</p> + +<p><blockquote> +Enhver har rett til å bevege seg fritt og til fritt å velge +oppholdssted innenfor en stats grenser. +</blockquote></p> + +<p>Det er altså en menneskerett å kunne bevege seg fritt i landet. +For å bevege seg fritt i landet, så må en kunne bevege seg uten å bli +sporet. Det vil i dagens samfunn innebære å bevege seg uten å legge +igjen digitale spor og uten å være radiomerket. Hvis en vet at ens +bevegelser, hvor en befinner seg når, og hvem som befinner seg i +nærheten, blir samlet inn og gjort tilgjengelig for fremmede, det være +seg myndighetene eller private organisasjoner, så kan en ikke lenger +bevege seg fritt. Dette gjør at det er en forutsetning for å ha glede +av retten til å bevege seg fritt i landet at en motstår fristelsen til +å legge igjen digitale spor når en betaler for seg. Rettigheter som +ikke blir brukt, blir fjernet. Den eneste måten i dag å unngå å legge +igjen digitale spor når en betaler for seg, er å betale med kontanter, +samt takke nei til å legge igjen navn og adresse (slik f.eks. Elkjøp +ber om &mdash; jeg sier de kan legge inn «anonym anonym» når +datasystemet deres trenger et navn). Personlig anbefaler jeg å +konsekvent bruke kontant betaling når man beveger seg rundt, for å +bidra til forsvaret av menneskerettighetene i Norge. Kanskje noe også +for deg? Merk at det ikke er tilstrekkelig for å unngå sporing å +betale med kontanter, men det er et lite steg i riktig retning.</p> + +<p>Det er flere andre argumenter i tillegg til +menneskerettighetsargumentet for å bruke kontanter. I går hadde +Dagbladet en utmerket kommentar av sin journalist John Olav Egeland om +hvilket +<a href="https://www.dagbladet.no/kultur/kontantlost-diktatur/70543434">kontantløst +diktatur</a> som venter oss hvis mange nok slutter å insistere på å +betale med kontanter. Jeg anbefaler deg å lese den.</p> + +<p>Som vanlig, hvis du bruker Bitcoin og ønsker å vise din støtte til +det jeg driver med, setter jeg pris på om du sender Bitcoin-donasjoner +til min adresse +<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>. +Merk, betaling med bitcoin er ikke anonymt. :)</p> - Generating 3D prints in Debian using Cura and Slic3r(-prusa) - http://people.skolelinux.org/pere/blog/Generating_3D_prints_in_Debian_using_Cura_and_Slic3r__prusa_.html - http://people.skolelinux.org/pere/blog/Generating_3D_prints_in_Debian_using_Cura_and_Slic3r__prusa_.html - Mon, 9 Oct 2017 10:50:00 +0200 - <p>At my nearby maker space, -<a href="http://sonen.ifi.uio.no/">Sonen</a>, I heard the story that it -was easier to generate gcode files for theyr 3D printers (Ultimake 2+) -on Windows and MacOS X than Linux, because the software involved had -to be manually compiled and set up on Linux while premade packages -worked out of the box on Windows and MacOS X. I found this annoying, -as the software involved, -<a href="https://github.com/Ultimaker/Cura">Cura</a>, is free software -and should be trivial to get up and running on Linux if someone took -the time to package it for the relevant distributions. I even found -<a href="https://bugs.debian.org/706656">a request for adding into -Debian</a> from 2013, which had seem some activity over the years but -never resulted in the software showing up in Debian. So a few days -ago I offered my help to try to improve the situation.</p> - -<p>Now I am very happy to see that all the packages required by a -working Cura in Debian are uploaded into Debian and waiting in the NEW -queue for the ftpmasters to have a look. You can track the progress -on -<a href="https://qa.debian.org/developer.php?email=3dprinter-general%40lists.alioth.debian.org">the -status page for the 3D printer team</a>.</p> - -<p>The uploaded packages are a bit behind upstream, and was uploaded -now to get slots in <a href="https://ftp-master.debian.org/new.html">the NEW -queue</a> while we work up updating the packages to the latest -upstream version.</p> - -<p>On a related note, two competitors for Cura, which I found harder -to use and was unable to configure correctly for Ultimaker 2+ in the -short time I spent on it, are already in Debian. If you are looking -for 3D printer "slicers" and want something already available in -Debian, check out -<a href="https://tracker.debian.org/pkg/slic3r">slic3r</a> and -<a href="https://tracker.debian.org/pkg/slic3r-prusa">slic3r-prusa</a>. -The latter is a fork of the former.</p> + Why is your site not using Content Security Policy / CSP? + http://people.skolelinux.org/pere/blog/Why_is_your_site_not_using_Content_Security_Policy___CSP_.html + http://people.skolelinux.org/pere/blog/Why_is_your_site_not_using_Content_Security_Policy___CSP_.html + Sun, 9 Dec 2018 15:00:00 +0100 + <p>Yesterday, I had the pleasure of watching on Frikanalen the OWASP +talk by Scott Helme titled +"<a href="https://frikanalen.no/video/626080/">What We’ve Learned From +Billions of Security Reports</a>". I had not heard of the +<a href="https://en.wikipedia.org/wiki/Content_Security_Policy">Content +Security Policy standard</a> nor its ability to "call home" when a +browser detect a policy breach (I do not follow web page design +development much these days), and found the talk very illuminating.</p> + +<p>The mechanism allow a web site owner to use HTTP headers to tell +visitors web browser which sources (internal and external) are allowed to +be used on the web site. Thus it become possible to enforce a "only +local content" policy despite web designers urge to fetch programs +from random sites on the Internet, like the one +<a href="https://securityaffairs.co/wordpress/68966/hacking/browsealoud-plugin-hack.html">enabling +the attack</a> reported by Scott Helme earlier this year.</p> + +<p>Using CSP seem like an obvious thing for a site admin to implement +to take some control over the information leak that occur when +external sources are used to render web pages, it is a mystery more +sites are not using CSP? It is being +<a href="https://www.w3.org/TR/CSP/">standardized under W3C</a> these +days, and is supposed by most web browsers</p> + +<p>I managed to find <a href="https://github.com/mozilla/django-csp">a +Django middleware for implementing CSP</a> and was happy to discover +it was already in Debian. I plan to use it to add CSP support to the +Frikanalen web site soon.</p> + +<p>As usual, if you use Bitcoin and want to show your support of my +activities, please send Bitcoin donations to my address +<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p> - Mangler du en skrue, eller har du en skrue løs? - http://people.skolelinux.org/pere/blog/Mangler_du_en_skrue__eller_har_du_en_skrue_l_s_.html - http://people.skolelinux.org/pere/blog/Mangler_du_en_skrue__eller_har_du_en_skrue_l_s_.html - Wed, 4 Oct 2017 09:40:00 +0200 - Når jeg holder på med ulike prosjekter, så trenger jeg stadig ulike -skruer. Det siste prosjektet jeg holder på med er å lage -<a href="https://www.thingiverse.com/thing:676916">en boks til en -HDMI-touch-skjerm</a> som skal brukes med Raspberry Pi. Boksen settes -sammen med skruer og bolter, og jeg har vært i tvil om hvor jeg kan -få tak i de riktige skruene. Clas Ohlson og Jernia i nærheten har -sjelden hatt det jeg trenger. Men her om dagen fikk jeg et fantastisk -tips for oss som bor i Oslo. -<a href="http://www.zachskruer.no/">Zachariassen Jernvare AS</a> i -<a href="http://www.openstreetmap.org/?mlat=59.93421&mlon=10.76795#map=19/59.93421/10.76795">Hegermannsgate -23A på Torshov</a> har et fantastisk utvalg, og åpent mellom 09:00 og -17:00. De selger skruer, muttere, bolter, skiver etc i løs vekt, og -så langt har jeg fått alt jeg har lett etter. De har i tillegg det -meste av annen jernvare, som verktøy, lamper, ledninger, etc. Jeg -håper de har nok kunder til å holde det gående lenge, da dette er en -butikk jeg kommer til å besøke ofte. Butikken er et funn å ha i -nabolaget for oss som liker å bygge litt selv. :)</p> + New and improved Frikanalen Kodi addon version 0.0.3 + http://people.skolelinux.org/pere/blog/New_and_improved_Frikanalen_Kodi_addon_version_0_0_3.html + http://people.skolelinux.org/pere/blog/New_and_improved_Frikanalen_Kodi_addon_version_0_0_3.html + Thu, 8 Nov 2018 10:30:00 +0100 + <p>If you read my blog regularly, you probably know I am involved in +running and developing the <a href="https://frikanalen.no/">Norwegian +TV channel Frikanalen</a>. It is an open channel, allowing everyone +in Norway to publish videos on a TV channel with national coverage. +You can think of it as Youtube for national television. +In addition to distribution on RiksTV and Uninett, Frikanalen is also +available as a Kodi addon. The last few days I have updated the code +to add more features. A +<a href="https://kodi.tv/addon/plugins-video-add-ons/frikanalen-nett-tv">new +and improved version 0.0.3 Frikanalen addon</a> was just made +available via the Kodi repositories. This new version include a +option to browse videos by category, as well as free text search +in the video archive. It will now also show the video duration in the +video lists, which were missing earlier. A new and experimental +link to the HD video stream currently being worked on is provided, for +those that want to see what the <a href="https://casparcg.com/">CasparCG</a> +output look like. The alternative is the SD video stream, generated +using MLT. CasparCG is controlled by our +<a href="https://github.com/Frikanalen/mltplayout/">mltplayout +server</a> which instead of talking to mlt is giving PLAY instructions +to the CasparCG server when it is time to start a new program.</p> + +<p>By now, you are probably wondering what kind of content is being +played on the channel. These days, it is filled with technical +presentations like those from <a href="https://www.nuug.no/">NUUG</a>, +<a href="https://www.debconf.org/">Debconf</a>, Makercon, and TED, +but there are also some periods with +<a href="https://www.empo.no/">EMPT TV</a> and +<a href="https://www.p7.no/">P7</a>. + +<p>As usual, if you use Bitcoin and want to show your support of my +activities, please send Bitcoin donations to my address +<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p> - Visualizing GSM radio chatter using gr-gsm and Hopglass - http://people.skolelinux.org/pere/blog/Visualizing_GSM_radio_chatter_using_gr_gsm_and_Hopglass.html - http://people.skolelinux.org/pere/blog/Visualizing_GSM_radio_chatter_using_gr_gsm_and_Hopglass.html - Fri, 29 Sep 2017 10:30:00 +0200 - <p>Every mobile phone announce its existence over radio to the nearby -mobile cell towers. And this radio chatter is available for anyone -with a radio receiver capable of receiving them. Details about the -mobile phones with very good accuracy is of course collected by the -phone companies, but this is not the topic of this blog post. The -mobile phone radio chatter make it possible to figure out when a cell -phone is nearby, as it include the SIM card ID (IMSI). By paying -attention over time, one can see when a phone arrive and when it leave -an area. I believe it would be nice to make this information more -available to the general public, to make more people aware of how -their phones are announcing their whereabouts to anyone that care to -listen.</p> - -<p>I am very happy to report that we managed to get something -visualizing this information up and running for -<a href="http://norwaymakers.org/osf17">Oslo Skaperfestival 2017</a> -(Oslo Makers Festival) taking place today and tomorrow at Deichmanske -library. The solution is based on the -<a href="http://people.skolelinux.org/pere/blog/Easier_recipe_to_observe_the_cell_phones_around_you.html">simple -recipe for listening to GSM chatter</a> I posted a few days ago, and -will show up at the stand of <a href="http://sonen.ifi.uio.no/">Åpen -Sone from the Computer Science department of the University of -Oslo</a>. The presentation will show the nearby mobile phones (aka -IMSIs) as dots in a web browser graph, with lines to the dot -representing mobile base station it is talking to. It was working in -the lab yesterday, and was moved into place this morning.</p> - -<p>We set up a fairly powerful desktop machine using Debian -Buster/Testing with several (five, I believe) RTL2838 DVB-T receivers -connected and visualize the visible cell phone towers using an -<a href="https://github.com/marlow925/hopglass">English version of -Hopglass</a>. A fairly powerfull machine is needed as the -grgsm_livemon_headless processes from -<a href="https://tracker.debian.org/pkg/gr-gsm">gr-gsm</a> converting -the radio signal to data packages is quite CPU intensive.</p> - -<p>The frequencies to listen to, are identified using a slightly -patched scan-and-livemon (to set the --args values for each receiver), -and the Hopglass data is generated using the -<a href="https://github.com/petterreinholdtsen/IMSI-catcher/tree/meshviewer-output">patches -in my meshviewer-output branch</a>. For some reason we could not get -more than four SDRs working. There is also a geographical map trying -to show the location of the base stations, but I believe their -coordinates are hardcoded to some random location in Germany, I -believe. The code should be replaced with code to look up location in -a text file, a sqlite database or one of the online databases -mentioned in -<a href="https://github.com/Oros42/IMSI-catcher/issues/14">the github -issue for the topic</a>. - -<p>If this sound interesting, visit the stand at the festival!</p> + Time for an official MIME type for patches? + http://people.skolelinux.org/pere/blog/Time_for_an_official_MIME_type_for_patches_.html + http://people.skolelinux.org/pere/blog/Time_for_an_official_MIME_type_for_patches_.html + Thu, 1 Nov 2018 08:15:00 +0100 + <p>As part of my involvement in +<a href="https://gitlab.com/OsloMet-ABI/nikita-noark5-core">the Nikita +archive API project</a>, I've been importing a fairly large lump of +emails into a test instance of the archive to see how well this would +go. I picked a subset of <a href="https://notmuchmail.org/">my +notmuch email database</a>, all public emails sent to me via +@lists.debian.org, giving me a set of around 216 000 emails to import. +In the process, I had a look at the various attachments included in +these emails, to figure out what to do with attachments, and noticed +that one of the most common attachment formats do not have +<a href="https://www.iana.org/assignments/media-types/media-types.xhtml">an +official MIME type</a> registered with IANA/IETF. The output from +diff, ie the input for patch, is on the top 10 list of formats +included in these emails. At the moment people seem to use either +text/x-patch or text/x-diff, but neither is officially registered. It +would be better if one official MIME type were registered and used +everywhere.</p> + +<p>To try to get one official MIME type for these files, I've brought +up the topic on +<a href="https://www.ietf.org/mailman/listinfo/media-types">the +media-types mailing list</a>. If you are interested in discussion +which MIME type to use as the official for patch files, or involved in +making software using a MIME type for patches, perhaps you would like +to join the discussion?</p> + +<p>As usual, if you use Bitcoin and want to show your support of my +activities, please send Bitcoin donations to my address +<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p> - Easier recipe to observe the cell phones around you - http://people.skolelinux.org/pere/blog/Easier_recipe_to_observe_the_cell_phones_around_you.html - http://people.skolelinux.org/pere/blog/Easier_recipe_to_observe_the_cell_phones_around_you.html - Sun, 24 Sep 2017 08:30:00 +0200 - <p>A little more than a month ago I wrote -<a href="http://people.skolelinux.org/pere/blog/Simpler_recipe_on_how_to_make_a_simple__7_IMSI_Catcher_using_Debian.html">how -to observe the SIM card ID (aka IMSI number) of mobile phones talking -to nearby mobile phone base stations using Debian GNU/Linux and a -cheap USB software defined radio</a>, and thus being able to pinpoint -the location of people and equipment (like cars and trains) with an -accuracy of a few kilometer. Since then we have worked to make the -procedure even simpler, and it is now possible to do this without any -manual frequency tuning and without building your own packages.</p> - -<p>The <a href="https://tracker.debian.org/pkg/gr-gsm">gr-gsm</a> -package is now included in Debian testing and unstable, and the -IMSI-catcher code no longer require root access to fetch and decode -the GSM data collected using gr-gsm.</p> - -<p>Here is an updated recipe, using packages built by Debian and a git -clone of two python scripts:</p> - -<ol> - -<li>Start with a Debian machine running the Buster version (aka - testing).</li> - -<li>Run '<tt>apt install gr-gsm python-numpy python-scipy - python-scapy</tt>' as root to install required packages.</li> - -<li>Fetch the code decoding GSM packages using '<tt>git clone - github.com/Oros42/IMSI-catcher.git</tt>'.</li> - -<li>Insert USB software defined radio supported by GNU Radio.</li> - -<li>Enter the IMSI-catcher directory and run '<tt>python - scan-and-livemon</tt>' to locate the frequency of nearby base - stations and start listening for GSM packages on one of them.</li> - -<li>Enter the IMSI-catcher directory and run '<tt>python - simple_IMSI-catcher.py</tt>' to display the collected information.</li> - -</ol> - -<p>Note, due to a bug somewhere the scan-and-livemon program (actually -<a href="https://github.com/ptrkrysik/gr-gsm/issues/336">its underlying -program grgsm_scanner</a>) do not work with the HackRF radio. It does -work with RTL 8232 and other similar USB radio receivers you can get -very cheaply -(<a href="https://www.ebay.com/sch/items/?_nkw=rtl+2832">for example -from ebay</a>), so for now the solution is to scan using the RTL radio -and only use HackRF for fetching GSM data.</p> - -<p>As far as I can tell, a cell phone only show up on one of the -frequencies at the time, so if you are going to track and count every -cell phone around you, you need to listen to all the frequencies used. -To listen to several frequencies, use the --numrecv argument to -scan-and-livemon to use several receivers. Further, I am not sure if -phones using 3G or 4G will show as talking GSM to base stations, so -this approach might not see all phones around you. I typically see -0-400 IMSI numbers an hour when looking around where I live.</p> - -<p>I've tried to run the scanner on a -<a href="https://wiki.debian.org/RaspberryPi">Raspberry Pi 2 and 3 -running Debian Buster</a>, but the grgsm_livemon_headless process seem -to be too CPU intensive to keep up. When GNU Radio print 'O' to -stdout, I am told there it is caused by a buffer overflow between the -radio and GNU Radio, caused by the program being unable to read the -GSM data fast enough. If you see a stream of 'O's from the terminal -where you started scan-and-livemon, you need a give the process more -CPU power. Perhaps someone are able to optimize the code to a point -where it become possible to set up RPi3 based GSM sniffers? I tried -using Raspbian instead of Debian, but there seem to be something wrong -with GNU Radio on raspbian, causing glibc to abort().</p> + Measuring the speaker frequency response using the AUDMES free software GUI - nice free software + http://people.skolelinux.org/pere/blog/Measuring_the_speaker_frequency_response_using_the_AUDMES_free_software_GUI___nice_free_software.html + http://people.skolelinux.org/pere/blog/Measuring_the_speaker_frequency_response_using_the_AUDMES_free_software_GUI___nice_free_software.html + Mon, 22 Oct 2018 08:40:00 +0200 + <p><img src="http://people.skolelinux.org/pere/blog/images/2018-10-22-audmes-measure-speakers.png" align="right" width="40%"/></p> + +<p>My current home stereo is a patchwork of various pieces I got on +flee markeds over the years. It is amazing what kind of equipment +show up there. I've been wondering for a while if it was possible to +measure how well this equipment is working together, and decided to +see how far I could get using free software. After trawling the web I +came across an article from DIY Audio and Video on +<a href="https://www.diyaudioandvideo.com/Tutorial/SpeakerResponseTesting/">Speaker +Testing and Analysis</a> describing how to test speakers, and it listing +several software options, among them +<a href="https://sourceforge.net/projects/audmes/">AUDio MEasurement +System (AUDMES)</a>. It is the only free software system I could find +focusing on measuring speakers and audio frequency response. In the +process I also found an interesting article from NOVO on +<a href="http://novo.press/understanding-speaker-specifications-and-frequency-response/">Understanding +Speaker Specifications and Frequency Response</a> and an article from +ecoustics on +<a href="https://www.ecoustics.com/articles/understanding-speaker-frequency-response/">Understanding +Speaker Frequency Response</a>, with a lot of information on what to +look for and how to interpret the graphs. Armed with this knowledge, +I set out to measure the state of my speakers.</p> + +<p>The first hurdle was that AUDMES hadn't seen a commit for 10 years +and did not build with current compilers and libraries. I got in +touch with its author, who no longer was spending time on the program +but gave me write access to the subversion repository on Sourceforge. +The end result is that now the code build on Linux and is capable of +saving and loading the collected frequency response data in CSV +format. The application is quite nice and flexible, and I was able to +select the input and output audio interfaces independently. This made +it possible to use a USB mixer as the input source, while sending +output via my laptop headphone connection. I lacked the hardware and +cabling to figure out a different way to get independent cabling to +speakers and microphone.</p> + +<p>Using this setup I could see how a large range of high frequencies +apparently were not making it out of my speakers. The picture show +the frequency response measurement of one of the speakers. Note the +frequency lines seem to be slightly misaligned, compared to the CSV +output from the program. I can not hear several of these are high +frequencies, according to measurement from +<a href="http://freehearingtestsoftware.com">Free Hearing Test +Software</a>, an freeware system to measure your hearing (still +looking for a free software alternative), so I do not know if they are +coming out out the speakers. I thus do not quite know how to figure +out if the missing frequencies is a problem with the microphone, the +amplifier or the speakers, but I managed to rule out the audio card in my +PC by measuring my Bose noise canceling headset using its own +microphone. This setup was able to see the high frequency tones, so +the problem with my stereo had to be in the amplifier or speakers.</p> + +<p>Anyway, to try to role out one factor I ended up picking up a new +set of speakers at a flee marked, and these work a lot better than the +old speakers, so I guess the microphone and amplifier is OK. If you +need to measure your own speakers, check out AUDMES. If more people +get involved, perhaps the project could become good enough to +<a href="https://bugs.debian.org/910876">include in Debian</a>? And if +you know of some other free software to measure speakers and amplifier +performance, please let me know. I am aware of the freeware option +<a href="https://www.roomeqwizard.com/">REW</a>, but I want something +that can be developed also when the vendor looses interest.</p> + +<p>As usual, if you use Bitcoin and want to show your support of my +activities, please send Bitcoin donations to my address +<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p> - Datalagringsdirektivet kaster skygger over Høyre og Arbeiderpartiet - http://people.skolelinux.org/pere/blog/Datalagringsdirektivet_kaster_skygger_over_H_yre_og_Arbeiderpartiet.html - http://people.skolelinux.org/pere/blog/Datalagringsdirektivet_kaster_skygger_over_H_yre_og_Arbeiderpartiet.html - Thu, 7 Sep 2017 21:35:00 +0200 - <p>For noen dager siden publiserte Jon Wessel-Aas en bloggpost om -«<a href="http://www.uhuru.biz/?p=1821">Konklusjonen om datalagring som -EU-kommisjonen ikke ville at vi skulle få se</a>». Det er en -interessant gjennomgang av EU-domstolens syn på snurpenotovervåkning -av befolkningen, som er klar på at det er i strid med -EU-lovgivingen.</p> - -<p>Valgkampen går for fullt i Norge, og om noen få dager er siste -frist for å avgi stemme. En ting er sikkert, Høyre og Arbeiderpartiet -får ikke min stemme -<a href="http://people.skolelinux.org/pere/blog/Datalagringsdirektivet_gj_r_at_Oslo_H_yre_og_Arbeiderparti_ikke_f_r_min_stemme_i__r.html">denne -gangen heller</a>. Jeg har ikke glemt at de tvang igjennom loven som -skulle pålegge alle data- og teletjenesteleverandører å overvåke alle -sine kunder. En lov som er vedtatt, og aldri opphevet igjen.</p> - -<p>Det er tydelig fra diskusjonen rundt grenseløs digital overvåkning -(eller "Digital Grenseforsvar" som det kalles i Orvellisk nytale) at -hverken Høyre og Arbeiderpartiet har noen prinsipielle sperrer mot å -overvåke hele befolkningen, og diskusjonen så langt tyder på at flere -av de andre partiene heller ikke har det. Mange av -<a href="https://data.holderdeord.no/votes/1301946411e">de som stemte -for Datalagringsdirektivet i Stortinget</a> (64 fra Arbeiderpartiet, -25 fra Høyre) er fortsatt aktive og argumenterer fortsatt for å radere -vekk mer av innbyggernes privatsfære.</p> - -<p>Når myndighetene demonstrerer sin mistillit til folket, tror jeg -folket selv bør legge litt innsats i å verne sitt privatliv, ved å ta -i bruk ende-til-ende-kryptert kommunikasjon med sine kjente og kjære, -og begrense hvor mye privat informasjon som deles med uvedkommende. -Det er jo ingenting som tyder på at myndighetene kommer til å være vår -privatsfære. -<a href="http://people.skolelinux.org/pere/blog/How_to_talk_with_your_loved_ones_in_private.html">Det -er mange muligheter</a>. Selv har jeg litt sans for -<a href="https://ring.cx/">Ring</a>, som er basert på p2p-teknologi -uten sentral kontroll, er fri programvare, og støtter meldinger, tale -og video. Systemet er tilgjengelig ut av boksen fra -<a href="https://tracker.debian.org/pkg/ring">Debian</a> og -<a href="https://launchpad.net/ubuntu/+source/ring">Ubuntu</a>, og det -finnes pakker for Android, MacOSX og Windows. Foreløpig er det få -brukere med Ring, slik at jeg også bruker -<a href="https://signal.org/">Signal</a> som nettleserutvidelse.</p> + Web browser integration of VLC with Bittorrent support + http://people.skolelinux.org/pere/blog/Web_browser_integration_of_VLC_with_Bittorrent_support.html + http://people.skolelinux.org/pere/blog/Web_browser_integration_of_VLC_with_Bittorrent_support.html + Sun, 21 Oct 2018 09:50:00 +0200 + <p>Bittorrent is as far as I know, currently the most efficient way to +distribute content on the Internet. It is used all by all sorts of +content providers, from national TV stations like +<a href="https://www.nrk.no/">NRK</a>, Linux distributors like +<a href="https://www.debian.org/">Debian</a> and +<a href="https://www.ubuntu.com/">Ubuntu</a>, and of course the +<a href="https://archive.org/">Internet archive</A>. + +<p>Almost a month ago +<a href="https://tracker.debian.org/pkg/vlc-plugin-bittorrent">a new +package adding Bittorrent support to VLC</a> became available in +Debian testing and unstable. To test it, simply install it like +this:</p> + +<p><pre> +apt install vlc-plugin-bittorrent +</pre></p> + +<p>Since the plugin was made available for the first time in Debian, +several improvements have been made to it. In version 2.2-4, now +available in both testing and unstable, a desktop file is provided to +teach browsers to start VLC when the user click on torrent files or +magnet links. The last part is thanks to me finally understanding +what the strange x-scheme-handler style MIME types in desktop files +are used for. By adding x-scheme-handler/magnet to the MimeType entry +in the desktop file, at least the browsers Firefox and Chromium will +suggest to start VLC when selecting a magnet URI on a web page. The +end result is that now, with the plugin installed in Buster and Sid, +one can visit any +<a href="https://archive.org/details/CopyingIsNotTheft1080p">Internet +Archive page with movies</a> using a web browser and click on the +torrent link to start streaming the movie.</p> + +<p>Note, there is still some misfeatures in the plugin. One is the +fact that it will hang and +<a href="https://github.com/johang/vlc-bittorrent/issues/13">block VLC +from exiting until the torrent streaming starts</a>. Another is the +fact that it +<a href="https://github.com/johang/vlc-bittorrent/issues/9">will pick +and play a random file in a multi file torrent</a>. This is not +always the video file you want. Combined with the first it can be a +bit hard to get the video streaming going. But when it work, it seem +to do a good job.</p> + +<p>For the Debian packaging, I would love to find a good way to test +if the plugin work with VLC using autopkgtest. I tried, but do not +know enough of the inner workings of VLC to get it working. For now +the autopkgtest script is only checking if the .so file was +successfully loaded by VLC. If you have any suggestions, please +submit a patch to the Debian bug tracking system.</p> + +<p>As usual, if you use Bitcoin and want to show your support of my +activities, please send Bitcoin donations to my address +<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p> - Simpler recipe on how to make a simple $7 IMSI Catcher using Debian - http://people.skolelinux.org/pere/blog/Simpler_recipe_on_how_to_make_a_simple__7_IMSI_Catcher_using_Debian.html - http://people.skolelinux.org/pere/blog/Simpler_recipe_on_how_to_make_a_simple__7_IMSI_Catcher_using_Debian.html - Wed, 9 Aug 2017 23:59:00 +0200 - <p>On friday, I came across an interesting article in the Norwegian -web based ICT news magazine digi.no on -<a href="https://www.digi.no/artikler/sikkerhetsforsker-lagde-enkel-imsi-catcher-for-60-kroner-na-kan-mobiler-kartlegges-av-alle/398588">how -to collect the IMSI numbers of nearby cell phones</a> using the cheap -DVB-T software defined radios. The article refered to instructions -and <a href="https://www.youtube.com/watch?v=UjwgNd_as30">a recipe by -Keld Norman on Youtube on how to make a simple $7 IMSI Catcher</a>, and I decided to test them out.</p> - -<p>The instructions said to use Ubuntu, install pip using apt (to -bypass apt), use pip to install pybombs (to bypass both apt and pip), -and the ask pybombs to fetch and build everything you need from -scratch. I wanted to see if I could do the same on the most recent -Debian packages, but this did not work because pybombs tried to build -stuff that no longer build with the most recent openssl library or -some other version skew problem. While trying to get this recipe -working, I learned that the apt->pip->pybombs route was a long detour, -and the only piece of software dependency missing in Debian was the -gr-gsm package. I also found out that the lead upstream developer of -gr-gsm (the name stand for GNU Radio GSM) project already had a set of -Debian packages provided in an Ubuntu PPA repository. All I needed to -do was to dget the Debian source package and built it.</p> - -<p>The IMSI collector is a python script listening for packages on the -loopback network device and printing to the terminal some specific GSM -packages with IMSI numbers in them. The code is fairly short and easy -to understand. The reason this work is because gr-gsm include a tool -to read GSM data from a software defined radio like a DVB-T USB stick -and other software defined radios, decode them and inject them into a -network device on your Linux machine (using the loopback device by -default). This proved to work just fine, and I've been testing the -collector for a few days now.</p> - -<p>The updated and simpler recipe is thus to</p> - -<ol> - -<li>start with a Debian machine running Stretch or newer,</li> - -<li>build and install the gr-gsm package available from -<a href="http://ppa.launchpad.net/ptrkrysik/gr-gsm/ubuntu/pool/main/g/gr-gsm/">http://ppa.launchpad.net/ptrkrysik/gr-gsm/ubuntu/pool/main/g/gr-gsm/</a>,</li> - -<li>clone the git repostory from <a href="https://github.com/Oros42/IMSI-catcher">https://github.com/Oros42/IMSI-catcher</a>,</li> - -<li>run grgsm_livemon and adjust the frequency until the terminal -where it was started is filled with a stream of text (meaning you -found a GSM station).</li> - -<li>go into the IMSI-catcher directory and run 'sudo python simple_IMSI-catcher.py' to extract the IMSI numbers.</li> - -</ol> - -<p>To make it even easier in the future to get this sniffer up and -running, I decided to package -<a href="https://github.com/ptrkrysik/gr-gsm/">the gr-gsm project</a> -for Debian (<a href="https://bugs.debian.org/871055">WNPP -#871055</a>), and the package was uploaded into the NEW queue today. -Luckily the gnuradio maintainer has promised to help me, as I do not -know much about gnuradio stuff yet.</p> - -<p>I doubt this "IMSI cacher" is anywhere near as powerfull as -commercial tools like -<a href="https://www.thespyphone.com/portable-imsi-imei-catcher/">The -Spy Phone Portable IMSI / IMEI Catcher</a> or the -<a href="https://en.wikipedia.org/wiki/Stingray_phone_tracker">Harris -Stingray</a>, but I hope the existance of cheap alternatives can make -more people realise how their whereabouts when carrying a cell phone -is easily tracked. Seeing the data flow on the screen, realizing that -I live close to a police station and knowing that the police is also -wearing cell phones, I wonder how hard it would be for criminals to -track the position of the police officers to discover when there are -police near by, or for foreign military forces to track the location -of the Norwegian military forces, or for anyone to track the location -of government officials...</p> - -<p>It is worth noting that the data reported by the IMSI-catcher -script mentioned above is only a fraction of the data broadcasted on -the GSM network. It will only collect one frequency at the time, -while a typical phone will be using several frequencies, and not all -phones will be using the frequencies tracked by the grgsm_livemod -program. Also, there is a lot of radio chatter being ignored by the -simple_IMSI-catcher script, which would be collected by extending the -parser code. I wonder if gr-gsm can be set up to listen to more than -one frequency?</p> + Release 0.2 of free software archive system Nikita announced + http://people.skolelinux.org/pere/blog/Release_0_2_of_free_software_archive_system_Nikita_announced.html + http://people.skolelinux.org/pere/blog/Release_0_2_of_free_software_archive_system_Nikita_announced.html + Thu, 18 Oct 2018 14:40:00 +0200 + <p>This morning, the new release of the +<a href="https://gitlab.com/OsloMet-ABI/nikita-noark5-core/">Nikita +Noark 5 core project</a> was +<a href="https://lists.nuug.no/pipermail/nikita-noark/2018-October/000406.html">announced +on the project mailing list</a>. The free software solution is an +implementation of the Norwegian archive standard Noark 5 used by +government offices in Norway. These were the changes in version 0.2 +since version 0.1.1 (from NEWS.md): + +<ul> + <li>Fix typos in REL names</li> + <li>Tidy up error message reporting</li> + <li>Fix issue where we used Integer.valueOf(), not Integer.getInteger()</li> + <li>Change some String handling to StringBuffer</li> + <li>Fix error reporting</li> + <li>Code tidy-up</li> + <li>Fix issue using static non-synchronized SimpleDateFormat to avoid + race conditions</li> + <li>Fix problem where deserialisers were treating integers as strings</li> + <li>Update methods to make them null-safe</li> + <li>Fix many issues reported by coverity</li> + <li>Improve equals(), compareTo() and hash() in domain model</li> + <li>Improvements to the domain model for metadata classes</li> + <li>Fix CORS issues when downloading document</li> + <li>Implementation of case-handling with registryEntry and document upload</li> + <li>Better support in Javascript for OPTIONS</li> + <li>Adding concept description of mail integration</li> + <li>Improve setting of default values for GET on ny-journalpost</li> + <li>Better handling of required values during deserialisation </li> + <li>Changed tilknyttetDato (M620) from date to dateTime</li> + <li>Corrected some opprettetDato (M600) (de)serialisation errors.</li> + <li>Improve parse error reporting.</li> + <li>Started on OData search and filtering.</li> + <li>Added Contributor Covenant Code of Conduct to project.</li> + <li>Moved repository and project from Github to Gitlab.</li> + <li>Restructured repository, moved code into src/ and web/.</li> + <li>Updated code to use Spring Boot version 2.</li> + <li>Added support for OAuth2 authentication.</li> + <li>Fixed several bugs discovered by Coverity.</li> + <li>Corrected handling of date/datetime fields.</li> + <li>Improved error reporting when rejecting during deserializatoin.</li> + <li>Adjusted default values provided for ny-arkivdel, ny-mappe, + ny-saksmappe, ny-journalpost and ny-dokumentbeskrivelse.</li> + <li>Several fixes for korrespondansepart*.</li> + <li>Updated web GUI: + <ul> + <li>Now handle both file upload and download.</li> + <li>Uses new OAuth2 authentication for login.</li> + <li>Forms now fetches default values from API using GET.</li> + <li>Added RFC 822 (email), TIFF and JPEG to list of possible file formats.</li> + </ul></li> +</ul> + +<p>The changes and improvements are extensive. Running diffstat on +the changes between git tab 0.1.1 and 0.2 show 1098 files changed, +108666 insertions(+), 54066 deletions(-).</p> + +<p>If free and open standardized archiving API sound interesting to +you, please contact us on IRC +(<a href="irc://irc.freenode.net/%23nikita">#nikita on +irc.freenode.net</a>) or email +(<a href="https://lists.nuug.no/mailman/listinfo/nikita-noark">nikita-noark +mailing list</a>).</p> + +<p>As usual, if you use Bitcoin and want to show your support of my +activities, please send Bitcoin donations to my address +<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>