X-Git-Url: http://pere.pagekite.me/gitweb/homepage.git/blobdiff_plain/5555b9e78965484460c4764b91c11fb8d75e0cf1..2aafae50dc90da8ae2432aaeca9569fbe49cf7d7:/blog/index.rss diff --git a/blog/index.rss b/blog/index.rss index 0a657f587a..0581cf3d48 100644 --- a/blog/index.rss +++ b/blog/index.rss @@ -7,664 +7,712 @@ - Detecting NFS hangs on Linux without hanging yourself... - http://people.skolelinux.org/pere/blog/Detecting_NFS_hangs_on_Linux_without_hanging_yourself___.html - http://people.skolelinux.org/pere/blog/Detecting_NFS_hangs_on_Linux_without_hanging_yourself___.html - Thu, 9 Mar 2017 15:20:00 +0100 - <p>Over the years, administrating thousand of NFS mounting linux -computers at the time, I often needed a way to detect if the machine -was experiencing NFS hang. If you try to use <tt>df</tt> or look at a -file or directory affected by the hang, the process (and possibly the -shell) will hang too. So you want to be able to detect this without -risking the detection process getting stuck too. It has not been -obvious how to do this. When the hang has lasted a while, it is -possible to find messages like these in dmesg:</p> - -<p><blockquote> -nfs: server nfsserver not responding, still trying -<br>nfs: server nfsserver OK -</blockquote></p> - -<p>It is hard to know if the hang is still going on, and it is hard to -be sure looking in dmesg is going to work. If there are lots of other -messages in dmesg the lines might have rotated out of site before they -are noticed.</p> - -<p>While reading through the nfs client implementation in linux kernel -code, I came across some statistics that seem to give a way to detect -it. The om_timeouts sunrpc value in the kernel will increase every -time the above log entry is inserted into dmesg. And after digging a -bit further, I discovered that this value show up in -/proc/self/mountstats on Linux.</p> - -<p>The mountstats content seem to be shared between files using the -same file system context, so it is enough to check one of the -mountstats files to get the state of the mount point for the machine. -I assume this will not show lazy umounted NFS points, nor NFS mount -points in a different process context (ie with a different filesystem -view), but that does not worry me.</p> - -<p>The content for a NFS mount point look similar to this:</p> - -<p><blockquote><pre> -[...] -device /dev/mapper/Debian-var mounted on /var with fstype ext3 -device nfsserver:/mnt/nfsserver/home0 mounted on /mnt/nfsserver/home0 with fstype nfs statvers=1.1 - opts: rw,vers=3,rsize=65536,wsize=65536,namlen=255,acregmin=3,acregmax=60,acdirmin=30,acdirmax=60,soft,nolock,proto=tcp,timeo=600,retrans=2,sec=sys,mountaddr=129.240.3.145,mountvers=3,mountport=4048,mountproto=udp,local_lock=all - age: 7863311 - caps: caps=0x3fe7,wtmult=4096,dtsize=8192,bsize=0,namlen=255 - sec: flavor=1,pseudoflavor=1 - events: 61063112 732346265 1028140 35486205 16220064 8162542 761447191 71714012 37189 3891185 45561809 110486139 4850138 420353 15449177 296502 52736725 13523379 0 52182 9016896 1231 0 0 0 0 0 - bytes: 166253035039 219519120027 0 0 40783504807 185466229638 11677877 45561809 - RPC iostats version: 1.0 p/v: 100003/3 (nfs) - xprt: tcp 925 1 6810 0 0 111505412 111480497 109 2672418560317 0 248 53869103 22481820 - per-op statistics - NULL: 0 0 0 0 0 0 0 0 - GETATTR: 61063106 61063108 0 9621383060 6839064400 453650 77291321 78926132 - SETATTR: 463469 463470 0 92005440 66739536 63787 603235 687943 - LOOKUP: 17021657 17021657 0 3354097764 4013442928 57216 35125459 35566511 - ACCESS: 14281703 14290009 5 2318400592 1713803640 1709282 4865144 7130140 - READLINK: 125 125 0 20472 18620 0 1112 1118 - READ: 4214236 4214237 0 715608524 41328653212 89884 22622768 22806693 - WRITE: 8479010 8494376 22 187695798568 1356087148 178264904 51506907 231671771 - CREATE: 171708 171708 0 38084748 46702272 873 1041833 1050398 - MKDIR: 3680 3680 0 773980 993920 26 23990 24245 - SYMLINK: 903 903 0 233428 245488 6 5865 5917 - MKNOD: 80 80 0 20148 21760 0 299 304 - REMOVE: 429921 429921 0 79796004 61908192 3313 2710416 2741636 - RMDIR: 3367 3367 0 645112 484848 22 5782 6002 - RENAME: 466201 466201 0 130026184 121212260 7075 5935207 5961288 - LINK: 289155 289155 0 72775556 67083960 2199 2565060 2585579 - READDIR: 2933237 2933237 0 516506204 13973833412 10385 3190199 3297917 - READDIRPLUS: 1652839 1652839 0 298640972 6895997744 84735 14307895 14448937 - FSSTAT: 6144 6144 0 1010516 1032192 51 9654 10022 - FSINFO: 2 2 0 232 328 0 1 1 - PATHCONF: 1 1 0 116 140 0 0 0 - COMMIT: 0 0 0 0 0 0 0 0 - -device binfmt_misc mounted on /proc/sys/fs/binfmt_misc with fstype binfmt_misc -[...] -</pre></blockquote></p> - -<p>The key number to look at is the third number in the per-op list. -It is the number of NFS timeouts experiences per file system -operation. Here 22 write timeouts and 5 access timeouts. If these -numbers are increasing, I believe the machine is experiencing NFS -hang. Unfortunately the timeout value do not start to increase right -away. The NFS operations need to time out first, and this can take a -while. The exact timeout value depend on the setup. For example the -defaults for TCP and UDP mount points are quite different, and the -timeout value is affected by the soft, hard, timeo and retrans NFS -mount options.</p> - -<p>The only way I have been able to get working on Debian and RedHat -Enterprise Linux for getting the timeout count is to peek in /proc/. -But according to -<ahref="http://docs.oracle.com/cd/E19253-01/816-4555/netmonitor-12/index.html">Solaris -10 System Administration Guide: Network Services</a>, the 'nfsstat -c' -command can be used to get these timeout values. But this do not work -on Linux, as far as I can tell. I -<ahref="http://bugs.debian.org/857043">asked Debian about this</a>, -but have not seen any replies yet.</p> - -<p>Is there a better way to figure out if a Linux NFS client is -experiencing NFS hangs? Is there a way to detect which processes are -affected? Is there a way to get the NFS mount going quickly once the -network problem causing the NFS hang has been cleared? I would very -much welcome some clues, as we regularly run into NFS hangs.</p> + Software created using taxpayers’ money should be Free Software + http://people.skolelinux.org/pere/blog/Software_created_using_taxpayers__money_should_be_Free_Software.html + http://people.skolelinux.org/pere/blog/Software_created_using_taxpayers__money_should_be_Free_Software.html + Thu, 30 Aug 2018 13:50:00 +0200 + <p>It might seem obvious that software created using tax money should +be available for everyone to use and improve. Free Software +Foundation Europe recentlystarted a campaign to help get more people +to understand this, and I just signed the petition on +<a href="https://publiccode.eu/">Public Money, Public Code</a> to help +them. I hope you too will do the same.</p> - How does it feel to be wiretapped, when you should be doing the wiretapping... - http://people.skolelinux.org/pere/blog/How_does_it_feel_to_be_wiretapped__when_you_should_be_doing_the_wiretapping___.html - http://people.skolelinux.org/pere/blog/How_does_it_feel_to_be_wiretapped__when_you_should_be_doing_the_wiretapping___.html - Wed, 8 Mar 2017 11:50:00 +0100 - <p>So the new president in the United States of America claim to be -surprised to discover that he was wiretapped during the election -before he was elected president. He even claim this must be illegal. -Well, doh, if it is one thing the confirmations from Snowden -documented, it is that the entire population in USA is wiretapped, one -way or another. Of course the president candidates were wiretapped, -alongside the senators, judges and the rest of the people in USA.</p> - -<p>Next, the Federal Bureau of Investigation ask the Department of -Justice to go public rejecting the claims that Donald Trump was -wiretapped illegally. I fail to see the relevance, given that I am -sure the surveillance industry in USA believe they have all the legal -backing they need to conduct mass surveillance on the entire -world.</p> - -<p>There is even the director of the FBI stating that he never saw an -order requesting wiretapping of Donald Trump. That is not very -surprising, given how the FISA court work, with all its activity being -secret. Perhaps he only heard about it?</p> - -<p>What I find most sad in this story is how Norwegian journalists -present it. In a news reports the other day in the radio from the -Norwegian National broadcasting Company (NRK), I heard the journalist -claim that 'the FBI denies any wiretapping', while the reality is that -'the FBI denies any illegal wiretapping'. There is a fundamental and -important difference, and it make me sad that the journalists are -unable to grasp it.</p> - -<p><strong>Update 2017-03-13:</strong> Look like -<a href="https://theintercept.com/2017/03/13/rand-paul-is-right-nsa-routinely-monitors-americans-communications-without-warrants/">The -Intercept report that US Senator Rand Paul confirm what I state above</a>.</p> + A bit more on privacy respecting health monitor / fitness tracker + http://people.skolelinux.org/pere/blog/A_bit_more_on_privacy_respecting_health_monitor___fitness_tracker.html + http://people.skolelinux.org/pere/blog/A_bit_more_on_privacy_respecting_health_monitor___fitness_tracker.html + Mon, 13 Aug 2018 09:00:00 +0200 + <p>A few days ago, I wondered if there are any privacy respecting +health monitors and/or fitness trackers available for sale these days. +I would like to buy one, but do not want to share my personal data +with strangers, nor be forced to have a mobile phone to get data out +of the unit. I've received some ideas, and would like to share them +with you. + +One interesting data point was a pointer to a Free Software app for +Android named +<a href="https://github.com/Freeyourgadget/Gadgetbridge/">Gadgetbridge</a>. +It provide cloudless collection and storing of data from a variety of +trackers. Its +<a href="https://github.com/Freeyourgadget/Gadgetbridge/#supported-devices">list +of supported devices</a> is a good indicator for units where the +protocol is fairly open, as it is obviously being handled by Free +Software. Other units are reportedly encrypting the collected +information with their own public key, making sure only the vendor +cloud service is able to extract data from the unit. The people +contacting me about Gadgetbirde said they were using +<a href="https://us.amazfit.com/shop/bip?variant=336750">Amazfit +Bip</a> and +<a href="http://www.xiaomimi6phone.com/xiaomi-mi-band-3-features-release-date-rumors/">Xiaomi +Band 3</a>.</p> + +<p>I also got a suggestion to look at some of the units from Garmin. +I was told their GPS watches can be connected via USB and show up as a +USB storage device with +<a href="https://www.gpsbabel.org/htmldoc-development/fmt_garmin_fit.html">Garmin +FIT files</a> containing the collected measurements. While +proprietary, FIT files apparently can be read at least by +<a href="https://www.gpsbabel.org">GPSBabel</a> and the +<a href="https://apps.nextcloud.com/apps/gpxpod">GpxPod</a> Nextcloud +app. It is unclear to me if they can read step count and heart rate +data. The person I talked to was using a +<a href="https://buy.garmin.com/en-US/US/p/564291">Garmin Forerunner +935</a>, which is a fairly expensive unit. I doubt it is worth it for +a unit where the vendor clearly is trying its best to move from open +to closed systems. I still remember when Garmin dropped NMEA support +in its GPSes.</p> + +<p>A final idea was to build ones own unit, perhaps by basing it on a +wearable hardware platforms like +<a href="https://learn.adafruit.com/flora-geo-watch">the Flora Geo +Watch</a>. Sound like fun, but I had more money than time to spend on +the topic, so I suspect it will have to wait for another time.</p> + +<p>While I was working on tracking down links, I came across an +inspiring TED talk by Dave Debronkart about +<a href="https://archive.org/details/DavedeBronkart_2010X">being a +e-patient</a>, and discovered the web site +<a href="https://participatorymedicine.org/epatients/">Participatory +Medicine</a>. If you too want to track your own health and fitness +without having information about your private life floating around on +computers owned by others, I recommend checking it out.</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> - Norwegian Bokmål translation of The Debian Administrator's Handbook complete, proofreading in progress - http://people.skolelinux.org/pere/blog/Norwegian_Bokm_l_translation_of_The_Debian_Administrator_s_Handbook_complete__proofreading_in_progress.html - http://people.skolelinux.org/pere/blog/Norwegian_Bokm_l_translation_of_The_Debian_Administrator_s_Handbook_complete__proofreading_in_progress.html - Fri, 3 Mar 2017 14:50:00 +0100 - <p>For almost a year now, we have been working on making a Norwegian -Bokmål edition of <a href="https://debian-handbook.info/">The Debian -Administrator's Handbook</a>. Now, thanks to the tireless effort of -Ole-Erik, Ingrid and Andreas, the initial translation is complete, and -we are working on the proof reading to ensure consistent language and -use of correct computer science terms. The plan is to make the book -available on paper, as well as in electronic form. For that to -happen, the proof reading must be completed and all the figures need -to be translated. If you want to help out, get in touch.</p> - -<p><a href="http://people.skolelinux.org/pere/debian-handbook/debian-handbook-nb-NO.pdf">A - -fresh PDF edition</a> in A4 format (the final book will have smaller -pages) of the book created every morning is available for -proofreading. If you find any errors, please -<a href="https://hosted.weblate.org/projects/debian-handbook/">visit -Weblate and correct the error</a>. The -<a href="http://l.github.io/debian-handbook/stat/nb-NO/index.html">state -of the translation including figures</a> is a useful source for those -provide Norwegian bokmål screen shots and figures.</p> + Privacy respecting health monitor / fitness tracker? + http://people.skolelinux.org/pere/blog/Privacy_respecting_health_monitor___fitness_tracker_.html + http://people.skolelinux.org/pere/blog/Privacy_respecting_health_monitor___fitness_tracker_.html + Tue, 7 Aug 2018 16:00:00 +0200 + <p>Dear lazyweb,</p> + +<p>I wonder, is there a fitness tracker / health monitor available for +sale today that respect the users privacy? With this I mean a +watch/bracelet capable of measuring pulse rate and other +fitness/health related values (and by all means, also the correct time +and location if possible), which is <strong>only</strong> provided for +me to extract/read from the unit with computer without a radio beacon +and Internet connection. In other words, it do not depend on a cell +phone app, and do make the measurements available via other peoples +computer (aka "the cloud"). The collected data should be available +using only free software. I'm not interested in depending on some +non-free software that will leave me high and dry some time in the +future. I've been unable to find any such unit. I would like to buy +it. The ones I have seen for sale here in Norway are proud to report +that they share my health data with strangers (aka "cloud enabled"). +Is there an alternative? I'm not interested in giving money to people +requiring me to accept "privacy terms" to allow myself to measure my +own health.</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> - Unlimited randomness with the ChaosKey? - http://people.skolelinux.org/pere/blog/Unlimited_randomness_with_the_ChaosKey_.html - http://people.skolelinux.org/pere/blog/Unlimited_randomness_with_the_ChaosKey_.html - Wed, 1 Mar 2017 20:50:00 +0100 - <p>A few days ago I ordered a small batch of -<a href="http://altusmetrum.org/ChaosKey/">the ChaosKey</a>, a small -USB dongle for generating entropy created by Bdale Garbee and Keith -Packard. Yesterday it arrived, and I am very happy to report that it -work great! According to its designers, to get it to work out of the -box, you need the Linux kernel version 4.1 or later. I tested on a -Debian Stretch machine (kernel version 4.9), and there it worked just -fine, increasing the available entropy very quickly. I wrote a small -test oneliner to test. It first print the current entropy level, -drain /dev/random, and then print the entropy level for five seconds. -Here is the situation without the ChaosKey inserted:</p> + Sharing images with friends and family using RSS and EXIF/XMP metadata + http://people.skolelinux.org/pere/blog/Sharing_images_with_friends_and_family_using_RSS_and_EXIF_XMP_metadata.html + http://people.skolelinux.org/pere/blog/Sharing_images_with_friends_and_family_using_RSS_and_EXIF_XMP_metadata.html + Tue, 31 Jul 2018 23:30:00 +0200 + <p>For a while now, I have looked for a sensible way to share images +with my family using a self hosted solution, as it is unacceptable to +place images from my personal life under the control of strangers +working for data hoarders like Google or Dropbox. The last few days I +have drafted an approach that might work out, and I would like to +share it with you. I would like to publish images on a server under +my control, and point some Internet connected display units using some +free and open standard to the images I published. As my primary +language is not limited to ASCII, I need to store metadata using +UTF-8. Many years ago, I hoped to find a digital photo frame capable +of reading a RSS feed with image references (aka using the +&lt;enclosure&gt; RSS tag), but was unable to find a current supplier +of such frames. In the end I gave up that approach.</p> + +<p>Some months ago, I discovered that +<a href="https://www.jwz.org/xscreensaver/">XScreensaver</a> is able to +read images from a RSS feed, and used it to set up a screen saver on +my home info screen, showing images from the Daily images feed from +NASA. This proved to work well. More recently I discovered that +<a href="https://kodi.tv">Kodi</a> (both using +<a href="https://www.openelec.tv/">OpenELEC</a> and +<a href="https://libreelec.tv">LibreELEC</a>) provide the +<a href="https://github.com/grinsted/script.screensaver.feedreader">Feedreader</a> +screen saver capable of reading a RSS feed with images and news. For +fun, I used it this summer to test Kodi on my parents TV by hooking up +a Raspberry PI unit with LibreELEC, and wanted to provide them with a +screen saver showing selected pictures from my selection.</p> + +<p>Armed with motivation and a test photo frame, I set out to generate +a RSS feed for the Kodi instance. I adjusted my <a +href="https://freedombox.org/">Freedombox</a> instance, created +/var/www/html/privatepictures/, wrote a small Perl script to extract +title and description metadata from the photo files and generate the +RSS file. I ended up using Perl instead of python, as the +libimage-exiftool-perl Debian package seemed to handle the EXIF/XMP +tags I ended up using, while python3-exif did not. The relevant EXIF +tags only support ASCII, so I had to find better alternatives. XMP +seem to have the support I need.</p> + +<p>I am a bit unsure which EXIF/XMP tags to use, as I would like to +use tags that can be easily added/updated using normal free software +photo managing software. I ended up using the tags set using this +exiftool command, as these tags can also be set using digiKam:</p> <blockquote><pre> -% cat /proc/sys/kernel/random/entropy_avail; \ - dd bs=1M if=/dev/random of=/dev/null count=1; \ - for n in $(seq 1 5); do \ - cat /proc/sys/kernel/random/entropy_avail; \ - sleep 1; \ - done -300 -0+1 oppføringer inn -0+1 oppføringer ut -28 byte kopiert, 0,000264565 s, 106 kB/s -4 -8 -12 -17 -21 -% +exiftool -headline='The RSS image title' \ + -description='The RSS image description.' \ + -subject+=for-family photo.jpeg </pre></blockquote> -<p>The entropy level increases by 3-4 every second. In such case any -application requiring random bits (like a HTTPS enabled web server) -will halt and wait for more entrpy. And here is the situation with -the ChaosKey inserted:</p> +<p>I initially tried the "-title" and "keyword" tags, but they were +invisible in digiKam, so I changed to "-headline" and "-subject". I +use the keyword/subject 'for-family' to flag that the photo should be +shared with my family. Images with this keyword set are located and +copied into my Freedombox for the RSS generating script to find.</p> -<blockquote><pre> -% cat /proc/sys/kernel/random/entropy_avail; \ - dd bs=1M if=/dev/random of=/dev/null count=1; \ - for n in $(seq 1 5); do \ - cat /proc/sys/kernel/random/entropy_avail; \ - sleep 1; \ - done -1079 -0+1 oppføringer inn -0+1 oppføringer ut -104 byte kopiert, 0,000487647 s, 213 kB/s -433 -1028 -1031 -1035 -1038 -% -</pre></blockquote> +<p>Are there better ways to do this? Get in touch if you have better +suggestions.</p> -<p>Quite the difference. :) I bought a few more than I need, in case -someone want to buy one here in Norway. :)</p> - -<p>Update: The dongle was presented at Debconf last year. You might -find <a href="https://debconf16.debconf.org/talks/94/">the talk -recording illuminating</a>. It explains exactly what the source of -randomness is, if you are unable to spot it from the schema drawing -available from the ChaosKey web site linked at the start of this blog -post.</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> - Detect OOXML files with undefined behaviour? - http://people.skolelinux.org/pere/blog/Detect_OOXML_files_with_undefined_behaviour_.html - http://people.skolelinux.org/pere/blog/Detect_OOXML_files_with_undefined_behaviour_.html - Tue, 21 Feb 2017 00:20:00 +0100 - <p>I just noticed -<a href="http://www.arkivrad.no/aktuelt/riksarkivarens-forskrift-pa-horing">the -new Norwegian proposal for archiving rules in the goverment</a> list -<a href="http://www.ecma-international.org/publications/standards/Ecma-376.htm">ECMA-376</a> -/ ISO/IEC 29500 (aka OOXML) as valid formats to put in long term -storage. Luckily such files will only be accepted based on -pre-approval from the National Archive. Allowing OOXML files to be -used for long term storage might seem like a good idea as long as we -forget that there are plenty of ways for a "valid" OOXML document to -have content with no defined interpretation in the standard, which -lead to a question and an idea.</p> - -<p>Is there any tool to detect if a OOXML document depend on such -undefined behaviour? It would be useful for the National Archive (and -anyone else interested in verifying that a document is well defined) -to have such tool available when considering to approve the use of -OOXML. I'm aware of the -<a href="https://github.com/arlm/officeotron/">officeotron OOXML -validator</a>, but do not know how complete it is nor if it will -report use of undefined behaviour. Are there other similar tools -available? Please send me an email if you know of any such tool.</p> + Simple streaming the Linux desktop to Kodi using GStreamer and RTP + http://people.skolelinux.org/pere/blog/Simple_streaming_the_Linux_desktop_to_Kodi_using_GStreamer_and_RTP.html + http://people.skolelinux.org/pere/blog/Simple_streaming_the_Linux_desktop_to_Kodi_using_GStreamer_and_RTP.html + Thu, 12 Jul 2018 17:55:00 +0200 + <p>Last night, I wrote +<a href="http://people.skolelinux.org/pere/blog/Streaming_the_Linux_desktop_to_Kodi_using_VLC_and_RTSP.html">a +recipe to stream a Linux desktop using VLC to a instance of Kodi</a>. +During the day I received valuable feedback, and thanks to the +suggestions I have been able to rewrite the recipe into a much simpler +approach requiring no setup at all. It is a single script that take +care of it all.</p> + +<p>This new script uses GStreamer instead of VLC to capture the +desktop and stream it to Kodi. This fixed the video quality issue I +saw initially. It further removes the need to add a m3u file on the +Kodi machine, as it instead connects to +<a href="https://kodi.wiki/view/JSON-RPC_API/v8">the JSON-RPC API in +Kodi</a> and simply ask Kodi to play from the stream created using +GStreamer. Streaming the desktop to Kodi now become trivial. Copy +the script below, run it with the DNS name or IP address of the kodi +server to stream to as the only argument, and watch your screen show +up on the Kodi screen. Note, it depend on multicast on the local +network, so if you need to stream outside the local network, the +script must be modified. Also note, I have no idea if audio work, as +I only care about the picture part.</p> + +<blockquote><pre> +#!/bin/sh +# +# Stream the Linux desktop view to Kodi. See +# http://people.skolelinux.org/pere/blog/Streaming_the_Linux_desktop_to_Kodi_using_VLC_and_RTSP.html +# for backgorund information. + +# Make sure the stream is stopped in Kodi and the gstreamer process is +# killed if something go wrong (for example if curl is unable to find the +# kodi server). Do the same when interrupting this script. +kodicmd() { + host="$1" + cmd="$2" + params="$3" + curl --silent --header 'Content-Type: application/json' \ + --data-binary "{ \"id\": 1, \"jsonrpc\": \"2.0\", \"method\": \"$cmd\", \"params\": $params }" \ + "http://$host/jsonrpc" +} +cleanup() { + if [ -n "$kodihost" ] ; then + # Stop the playing when we end + playerid=$(kodicmd "$kodihost" Player.GetActivePlayers "{}" | + jq .result[].playerid) + kodicmd "$kodihost" Player.Stop "{ \"playerid\" : $playerid }" > /dev/null + fi + if [ "$gstpid" ] && kill -0 "$gstpid" >/dev/null 2>&1; then + kill "$gstpid" + fi +} +trap cleanup EXIT INT + +if [ -n "$1" ]; then + kodihost=$1 + shift +else + kodihost=kodi.local +fi + +mcast=239.255.0.1 +mcastport=1234 +mcastttl=1 + +pasrc=$(pactl list | grep -A2 'Source #' | grep 'Name: .*\.monitor$' | \ + cut -d" " -f2|head -1) +gst-launch-1.0 ximagesrc use-damage=0 ! video/x-raw,framerate=30/1 ! \ + videoconvert ! queue2 ! \ + x264enc bitrate=8000 speed-preset=superfast tune=zerolatency qp-min=30 \ + key-int-max=15 bframes=2 ! video/x-h264,profile=high ! queue2 ! \ + mpegtsmux alignment=7 name=mux ! rndbuffersize max=1316 min=1316 ! \ + udpsink host=$mcast port=$mcastport ttl-mc=$mcastttl auto-multicast=1 sync=0 \ + pulsesrc device=$pasrc ! audioconvert ! queue2 ! avenc_aac ! queue2 ! mux. \ + > /dev/null 2>&1 & +gstpid=$! + +# Give stream a second to get going +sleep 1 + +# Ask kodi to start streaming using its JSON-RPC API +kodicmd "$kodihost" Player.Open \ + "{\"item\": { \"file\": \"udp://@$mcast:$mcastport\" } }" > /dev/null + +# wait for gst to end +wait "$gstpid" +</pre></blockquote> + +<p>I hope you find the approach useful. I know I do.</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> - Ruling ignored our objections to the seizure of popcorn-time.no (#domstolkontroll) - http://people.skolelinux.org/pere/blog/Ruling_ignored_our_objections_to_the_seizure_of_popcorn_time_no___domstolkontroll_.html - http://people.skolelinux.org/pere/blog/Ruling_ignored_our_objections_to_the_seizure_of_popcorn_time_no___domstolkontroll_.html - Mon, 13 Feb 2017 21:30:00 +0100 - <p>A few days ago, we received the ruling from -<a href="http://people.skolelinux.org/pere/blog/A_day_in_court_challenging_seizure_of_popcorn_time_no_for__domstolkontroll.html">my -day in court</a>. The case in question is a challenge of the seizure -of the DNS domain popcorn-time.no. The ruling simply did not mention -most of our arguments, and seemed to take everything ØKOKRIM said at -face value, ignoring our demonstration and explanations. But it is -hard to tell for sure, as we still have not seen most of the documents -in the case and thus were unprepared and unable to contradict several -of the claims made in court by the opposition. We are considering an -appeal, but it is partly a question of funding, as it is costing us -quite a bit to pay for our lawyer. If you want to help, please -<a href="http://www.nuug.no/dns-beslag-donasjon.shtml">donate to the -NUUG defense fund</a>.</p> - -<p>The details of the case, as far as we know it, is available in -Norwegian from -<a href="https://www.nuug.no/news/tags/dns-domenebeslag/">the NUUG -blog</a>. This also include -<a href="https://www.nuug.no/news/Avslag_etter_rettslig_h_ring_om_DNS_beslaget___vurderer_veien_videre.shtml">the -ruling itself</a>.</p> + Streaming the Linux desktop to Kodi using VLC and RTSP + http://people.skolelinux.org/pere/blog/Streaming_the_Linux_desktop_to_Kodi_using_VLC_and_RTSP.html + http://people.skolelinux.org/pere/blog/Streaming_the_Linux_desktop_to_Kodi_using_VLC_and_RTSP.html + Thu, 12 Jul 2018 02:00:00 +0200 + <p>PS: See +<ahref="http://people.skolelinux.org/pere/blog/Simple_streaming_the_Linux_desktop_to_Kodi_using_GStreamer_and_RTP.html">the +followup post</a> for a even better approach.</p> + +<p>A while back, I was asked by a friend how to stream the desktop to +my projector connected to Kodi. I sadly had to admit that I had no +idea, as it was a task I never had tried. Since then, I have been +looking for a way to do so, preferable without much extra software to +install on either side. Today I found a way that seem to kind of +work. Not great, but it is a start.</p> + +<p>I had a look at several approaches, for example +<a href="https://github.com/mfoetsch/dlna_live_streaming">using uPnP +DLNA as described in 2011</a>, but it required a uPnP server, fuse and +local storage enough to store the stream locally. This is not going +to work well for me, lacking enough free space, and it would +impossible for my friend to get working.</p> + +<p>Next, it occurred to me that perhaps I could use VLC to create a +video stream that Kodi could play. Preferably using +broadcast/multicast, to avoid having to change any setup on the Kodi +side when starting such stream. Unfortunately, the only recipe I +could find using multicast used the rtp protocol, and this protocol +seem to not be supported by Kodi.</p> + +<p>On the other hand, the rtsp protocol is working! Unfortunately I +have to specify the IP address of the streaming machine in both the +sending command and the file on the Kodi server. But it is showing my +desktop, and thus allow us to have a shared look on the big screen at +the programs I work on.</p> + +<p>I did not spend much time investigating codeces. I combined the +rtp and rtsp recipes from +<a href="https://wiki.videolan.org/Documentation:Streaming_HowTo/Command_Line_Examples/">the +VLC Streaming HowTo/Command Line Examples</a>, and was able to get +this working on the desktop/streaming end.</p> + +<blockquote><pre> +vlc screen:// --sout \ + '#transcode{vcodec=mp4v,acodec=mpga,vb=800,ab=128}:rtp{dst=projector.local,port=1234,sdp=rtsp://192.168.11.4:8080/test.sdp}' +</pre></blockquote> + +<p>I ssh-ed into my Kodi box and created a file like this with the +same IP address:</p> + +<blockquote><pre> +echo rtsp://192.168.11.4:8080/test.sdp \ + > /storage/videos/screenstream.m3u +</pre></blockquote> + +<p>Note the 192.168.11.4 IP address is my desktops IP address. As far +as I can tell the IP must be hardcoded for this to work. In other +words, if someone elses machine is going to do the steaming, you have +to update screenstream.m3u on the Kodi machine and adjust the vlc +recipe. To get started, locate the file in Kodi and select the m3u +file while the VLC stream is running. The desktop then show up in my +big screen. :)</p> + +<p>When using the same technique to stream a video file with audio, +the audio quality is really bad. No idea if the problem is package +loss or bad parameters for the transcode. I do not know VLC nor Kodi +enough to tell.</p> + +<p><strong>Update 2018-07-12</strong>: Johannes Schauer send me a few +succestions and reminded me about an important step. The "screen:" +input source is only available once the vlc-plugin-access-extra +package is installed on Debian. Without it, you will see this error +message: "VLC is unable to open the MRL 'screen://'. Check the log +for details." He further found that it is possible to drop some parts +of the VLC command line to reduce the amount of hardcoded information. +It is also useful to consider using cvlc to avoid having the VLC +window in the desktop view. In sum, this give us this command line on +the source end + +<blockquote><pre> +cvlc screen:// --sout \ + '#transcode{vcodec=mp4v,acodec=mpga,vb=800,ab=128}:rtp{sdp=rtsp://:8080/}' +</pre></blockquote> + +<p>and this on the Kodi end<p> + +<blockquote><pre> +echo rtsp://192.168.11.4:8080/ \ + > /storage/videos/screenstream.m3u +</pre></blockquote> + +<p>Still bad image quality, though. But I did discover that streaming +a DVD using dvdsimple:///dev/dvd as the source had excellent video and +audio quality, so I guess the issue is in the input or transcoding +parts, not the rtsp part. I've tried to change the vb and ab +parameters to use more bandwidth, but it did not make a +difference.</p> + +<p>I further received a suggestion from Einar Haraldseid to try using +gstreamer instead of VLC, and this proved to work great! He also +provided me with the trick to get Kodi to use a multicast stream as +its source. By using this monstrous oneliner, I can stream my desktop +with good video quality in reasonable framerate to the 239.255.0.1 +multicast address on port 1234: + +<blockquote><pre> +gst-launch-1.0 ximagesrc use-damage=0 ! video/x-raw,framerate=30/1 ! \ + videoconvert ! queue2 ! \ + x264enc bitrate=8000 speed-preset=superfast tune=zerolatency qp-min=30 \ + key-int-max=15 bframes=2 ! video/x-h264,profile=high ! queue2 ! \ + mpegtsmux alignment=7 name=mux ! rndbuffersize max=1316 min=1316 ! \ + udpsink host=239.255.0.1 port=1234 ttl-mc=1 auto-multicast=1 sync=0 \ + pulsesrc device=$(pactl list | grep -A2 'Source #' | \ + grep 'Name: .*\.monitor$' | cut -d" " -f2|head -1) ! \ + audioconvert ! queue2 ! avenc_aac ! queue2 ! mux. +</pre></blockquote> + +<p>and this on the Kodi end<p> + +<blockquote><pre> +echo udp://@239.255.0.1:1234 \ + > /storage/videos/screenstream.m3u +</pre></blockquote> + +<p>Note the trick to pick a valid pulseaudio source. It might not +pick the one you need. This approach will of course lead to trouble +if more than one source uses the same multicast port and address. +Note the ttl-mc=1 setting, which limit the multicast packages to the +local network. If the value is increased, your screen will be +broadcasted further, one network "hop" for each increase (read up on +multicast to learn more. :)!</p> + +<p>Having cracked how to get Kodi to receive multicast streams, I +could use this VLC command to stream to the same multicast address. +The image quality is way better than the rtsp approach, but gstreamer +seem to be doing a better job.</p> + +<blockquote><pre> +cvlc screen:// --sout '#transcode{vcodec=mp4v,acodec=mpga,vb=800,ab=128}:rtp{mux=ts,dst=239.255.0.1,port=1234,sdp=sap}' +</pre></blockquote> + +<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 day in court challenging seizure of popcorn-time.no for #domstolkontroll - http://people.skolelinux.org/pere/blog/A_day_in_court_challenging_seizure_of_popcorn_time_no_for__domstolkontroll.html - http://people.skolelinux.org/pere/blog/A_day_in_court_challenging_seizure_of_popcorn_time_no_for__domstolkontroll.html - Fri, 3 Feb 2017 11:10:00 +0100 - <p align="center"><img width="70%" src="http://people.skolelinux.org/pere/blog/images/2017-02-01-popcorn-time-in-court.jpeg"></p> - -<p>On Wednesday, I spent the entire day in court in Follo Tingrett -representing <a href="https://www.nuug.no/">the member association -NUUG</a>, alongside <a href="https://www.efn.no/">the member -association EFN</a> and <a href="http://www.imc.no">the DNS registrar -IMC</a>, challenging the seizure of the DNS name popcorn-time.no. It -was interesting to sit in a court of law for the first time in my -life. Our team can be seen in the picture above: attorney Ola -Tellesbø, EFN board member Tom Fredrik Blenning, IMC CEO Morten Emil -Eriksen and NUUG board member Petter Reinholdtsen.</p> - -<p><a href="http://www.domstol.no/no/Enkelt-domstol/follo-tingrett/Nar-gar-rettssaken/Beramming/?cid=AAAA1701301512081262234UJFBVEZZZZZEJBAvtale">The -case at hand</a> is that the Norwegian National Authority for -Investigation and Prosecution of Economic and Environmental Crime (aka -Økokrim) decided on their own, to seize a DNS domain early last -year, without following -<a href="https://www.norid.no/no/regelverk/navnepolitikk/#link12">the -official policy of the Norwegian DNS authority</a> which require a -court decision. The web site in question was a site covering Popcorn -Time. And Popcorn Time is the name of a technology with both legal -and illegal applications. Popcorn Time is a client combining -searching a Bittorrent directory available on the Internet with -downloading/distribute content via Bittorrent and playing the -downloaded content on screen. It can be used illegally if it is used -to distribute content against the will of the right holder, but it can -also be used legally to play a lot of content, for example the -millions of movies -<a href="https://archive.org/details/movies">available from the -Internet Archive</a> or the collection -<a href="http://vodo.net/films/">available from Vodo</a>. We created -<a href="magnet:?xt=urn:btih:86c1802af5a667ca56d3918aecb7d3c0f7173084&dn=PresentasjonFolloTingrett.mov&tr=udp%3A%2F%2Fpublic.popcorn-tracker.org%3A6969%2Fannounce">a -video demonstrating legally use of Popcorn Time</a> and played it in -Court. It can of course be downloaded using Bittorrent.</p> - -<p>I did not quite know what to expect from a day in court. The -government held on to their version of the story and we held on to -ours, and I hope the judge is able to make sense of it all. We will -know in two weeks time. Unfortunately I do not have high hopes, as -the Government have the upper hand here with more knowledge about the -case, better training in handling criminal law and in general higher -standing in the courts than fairly unknown DNS registrar and member -associations. It is expensive to be right also in Norway. So far the -case have cost more than NOK 70 000,-. To help fund the case, NUUG -and EFN have asked for donations, and managed to collect around NOK 25 -000,- so far. Given the presentation from the Government, I expect -the government to appeal if the case go our way. And if the case do -not go our way, I hope we have enough funding to appeal.</p> - -<p>From the other side came two people from Økokrim. On the benches, -appearing to be part of the group from the government were two people -from the Simonsen Vogt Wiik lawyer office, and three others I am not -quite sure who was. Økokrim had proposed to present two witnesses -from The Motion Picture Association, but this was rejected because -they did not speak Norwegian and it was a bit late to bring in a -translator, but perhaps the two from MPA were present anyway. All -seven appeared to know each other. Good to see the case is take -seriously.</p> - -<p>If you, like me, believe the courts should be involved before a DNS -domain is hijacked by the government, or you believe the Popcorn Time -technology have a lot of useful and legal applications, I suggest you -too <a href="http://www.nuug.no/dns-beslag-donasjon.shtml">donate to -the NUUG defense fund</a>. Both Bitcoin and bank transfer are -available. If NUUG get more than we need for the legal action (very -unlikely), the rest will be spend promoting free software, open -standards and unix-like operating systems in Norway, so no matter what -happens the money will be put to good use.</p> - -<p>If you want to lean more about the case, I recommend you check out -<a href="https://www.nuug.no/news/tags/dns-domenebeslag/">the blog -posts from NUUG covering the case</a>. They cover the legal arguments -on both sides.</p> + What is the most supported MIME type in Debian in 2018? + http://people.skolelinux.org/pere/blog/What_is_the_most_supported_MIME_type_in_Debian_in_2018_.html + http://people.skolelinux.org/pere/blog/What_is_the_most_supported_MIME_type_in_Debian_in_2018_.html + Mon, 9 Jul 2018 08:05:00 +0200 + <p>Five years ago, +<a href="http://people.skolelinux.org/pere/blog/What_is_the_most_supported_MIME_type_in_Debian_.html">I +measured what the most supported MIME type in Debian was</a>, by +analysing the desktop files in all packages in the archive. Since +then, the DEP-11 AppStream system has been put into production, making +the task a lot easier. This made me want to repeat the measurement, +to see how much things changed. Here are the new numbers, for +unstable only this time: + +<p><strong>Debian Unstable:</strong></p> + +<pre> + count MIME type + ----- ----------------------- + 56 image/jpeg + 55 image/png + 49 image/tiff + 48 image/gif + 39 image/bmp + 38 text/plain + 37 audio/mpeg + 34 application/ogg + 33 audio/x-flac + 32 audio/x-mp3 + 30 audio/x-wav + 30 audio/x-vorbis+ogg + 29 image/x-portable-pixmap + 27 inode/directory + 27 image/x-portable-bitmap + 27 audio/x-mpeg + 26 application/x-ogg + 25 audio/x-mpegurl + 25 audio/ogg + 24 text/html +</pre> + +<p>The list was created like this using a sid chroot: "cat +/var/lib/apt/lists/*sid*_dep11_Components-amd64.yml.gz| zcat | awk '/^ +- \S+\/\S+$/ {print $2 }' | sort | uniq -c | sort -nr | head -20"</p> + +<p>It is interesting to see how image formats have passed text/plain +as the most announced supported MIME type. These days, thanks to the +AppStream system, if you run into a file format you do not know, and +want to figure out which packages support the format, you can find the +MIME type of the file using "file --mime &lt;filename&gt;", and then +look up all packages announcing support for this format in their +AppStream metadata (XML or .desktop file) using "appstreamcli +what-provides mimetype &lt;mime-type&gt;. For example if you, like +me, want to know which packages support inode/directory, you can get a +list like this:</p> + +<p><blockquote><pre> +% appstreamcli what-provides mimetype inode/directory | grep Package: | sort +Package: anjuta +Package: audacious +Package: baobab +Package: cervisia +Package: chirp +Package: dolphin +Package: doublecmd-common +Package: easytag +Package: enlightenment +Package: ephoto +Package: filelight +Package: gwenview +Package: k4dirstat +Package: kaffeine +Package: kdesvn +Package: kid3 +Package: kid3-qt +Package: nautilus +Package: nemo +Package: pcmanfm +Package: pcmanfm-qt +Package: qweborf +Package: ranger +Package: sirikali +Package: spacefm +Package: spacefm +Package: vifm +% +</pre></blockquote></p> + +<p>Using the same method, I can quickly discover that the Sketchup file +format is not yet supported by any package in Debian:</p> + +<p><blockquote><pre> +% appstreamcli what-provides mimetype application/vnd.sketchup.skp +Could not find component providing 'mimetype::application/vnd.sketchup.skp'. +% +</pre></blockquote></p> + +<p>Yesterday I used it to figure out which packages support the STL 3D +format:</p> + +<p><blockquote><pre> +% appstreamcli what-provides mimetype application/sla|grep Package +Package: cura +Package: meshlab +Package: printrun +% +</pre></blockquote></p> + +<p>PS: A new version of Cura was uploaded to Debian yesterday.</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> - Nasjonalbiblioteket avslutter sin ulovlige bruk av Google Skjemaer - http://people.skolelinux.org/pere/blog/Nasjonalbiblioteket_avslutter_sin_ulovlige_bruk_av_Google_Skjemaer.html - http://people.skolelinux.org/pere/blog/Nasjonalbiblioteket_avslutter_sin_ulovlige_bruk_av_Google_Skjemaer.html - Thu, 12 Jan 2017 09:40:00 +0100 - <p>I dag fikk jeg en skikkelig gladmelding. Bakgrunnen er at før jul -arrangerte Nasjonalbiblioteket -<a href="http://www.nb.no/Bibliotekutvikling/Kunnskapsorganisering/Nasjonalt-verksregister/Seminar-om-verksregister">et -seminar om sitt knakende gode tiltak «verksregister»</a>. Eneste -måten å melde seg på dette seminaret var å sende personopplysninger -til Google via Google Skjemaer. Dette syntes jeg var tvilsom praksis, -da det bør være mulig å delta på seminarer arrangert av det offentlige -uten å måtte dele sine interesser, posisjon og andre -personopplysninger med Google. Jeg ba derfor om innsyn via -<a href="https://www.mimesbronn.no/">Mimes brønn</a> i -<a href="https://www.mimesbronn.no/request/personopplysninger_til_google_sk">avtaler -og vurderinger Nasjonalbiblioteket hadde rundt dette</a>. -Personopplysningsloven legger klare rammer for hva som må være på -plass før en kan be tredjeparter, spesielt i utlandet, behandle -personopplysninger på sine vegne, så det burde eksistere grundig -dokumentasjon før noe slikt kan bli lovlig. To jurister hos -Nasjonalbiblioteket mente først dette var helt i orden, og at Googles -standardavtale kunne brukes som databehandlingsavtale. Det syntes jeg -var merkelig, men har ikke hatt kapasitet til å følge opp saken før -for to dager siden.</p> - -<p>Gladnyheten i dag, som kom etter at jeg tipset Nasjonalbiblioteket -om at Datatilsynet underkjente Googles standardavtaler som -databehandleravtaler i 2011, er at Nasjonalbiblioteket har bestemt seg -for å avslutte bruken av Googles Skjemaer/Apps og gå i dialog med DIFI -for å finne bedre måter å håndtere påmeldinger i tråd med -personopplysningsloven. Det er fantastisk å se at av og til hjelper -det å spørre hva i alle dager det offentlige holder på med.</p> + Debian APT upgrade without enough free space on the disk... + http://people.skolelinux.org/pere/blog/Debian_APT_upgrade_without_enough_free_space_on_the_disk___.html + http://people.skolelinux.org/pere/blog/Debian_APT_upgrade_without_enough_free_space_on_the_disk___.html + Sun, 8 Jul 2018 12:10:00 +0200 + <p>Quite regularly, I let my Debian Sid/Unstable chroot stay untouch +for a while, and when I need to update it there is not enough free +space on the disk for apt to do a normal 'apt upgrade'. I normally +would resolve the issue by doing 'apt install &lt;somepackages&gt;' to +upgrade only some of the packages in one batch, until the amount of +packages to download fall below the amount of free space available. +Today, I had about 500 packages to upgrade, and after a while I got +tired of trying to install chunks of packages manually. I concluded +that I did not have the spare hours required to complete the task, and +decided to see if I could automate it. I came up with this small +script which I call 'apt-in-chunks':</p> + +<p><blockquote><pre> +#!/bin/sh +# +# Upgrade packages when the disk is too full to upgrade every +# upgradable package in one lump. Fetching packages to upgrade using +# apt, and then installing using dpkg, to avoid changing the package +# flag for manual/automatic. + +set -e + +ignore() { + if [ "$1" ]; then + grep -v "$1" + else + cat + fi +} + +for p in $(apt list --upgradable | ignore "$@" |cut -d/ -f1 | grep -v '^Listing...'); do + echo "Upgrading $p" + apt clean + apt install --download-only -y $p + for f in /var/cache/apt/archives/*.deb; do + if [ -e "$f" ]; then + dpkg -i /var/cache/apt/archives/*.deb + break + fi + done +done +</pre></blockquote></p> + +<p>The script will extract the list of packages to upgrade, try to +download the packages needed to upgrade one package, install the +downloaded packages using dpkg. The idea is to upgrade packages +without changing the APT mark for the package (ie the one recording of +the package was manually requested or pulled in as a dependency). To +use it, simply run it as root from the command line. If it fail, try +'apt install -f' to clean up the mess and run the script again. This +might happen if the new packages conflict with one of the old +packages. dpkg is unable to remove, while apt can do this.</p> + +<p>It take one option, a package to ignore in the list of packages to +upgrade. The option to ignore a package is there to be able to skip +the packages that are simply too large to unpack. Today this was +'ghc', but I have run into other large packages causing similar +problems earlier (like TeX).</p> + +<p>Update 2018-07-08: Thanks to Paul Wise, I am aware of two +alternative ways to handle this. The "unattended-upgrades +--minimal-upgrade-steps" option will try to calculate upgrade sets for +each package to upgrade, and then upgrade them in order, smallest set +first. It might be a better option than my above mentioned script. +Also, "aptutude upgrade" can upgrade single packages, thus avoiding +the need for using "dpkg -i" in the script above.</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> - Bryter NAV sin egen personvernerklæring? - http://people.skolelinux.org/pere/blog/Bryter_NAV_sin_egen_personvernerkl_ring_.html - http://people.skolelinux.org/pere/blog/Bryter_NAV_sin_egen_personvernerkl_ring_.html - Wed, 11 Jan 2017 06:50:00 +0100 - <p>Jeg leste med interesse en nyhetssak hos -<a href="http://www.digi.no/artikler/nav-avslorer-trygdemisbruk-ved-a-spore-ip-adresser/367394">digi.no</a> -og -<a href="https://www.nrk.no/buskerud/trygdesvindlere-avslores-av-utenlandske-ip-adresser-1.13313461">NRK</a> -om at det ikke bare er meg, men at også NAV bedriver geolokalisering -av IP-adresser, og at det gjøres analyse av IP-adressene til de som -sendes inn meldekort for å se om meldekortet sendes inn fra -utenlandske IP-adresser. Politiadvokat i Drammen, Hans Lyder Haare, -er sitert i NRK på at «De to er jo blant annet avslørt av -IP-adresser. At man ser at meldekortet kommer fra utlandet.»</p> - -<p>Jeg synes det er fint at det blir bedre kjent at IP-adresser -knyttes til enkeltpersoner og at innsamlet informasjon brukes til å -stedsbestemme personer også av aktører her i Norge. Jeg ser det som -nok et argument for å bruke -<a href="https://www.torproject.org/">Tor</a> så mye som mulig for å -gjøre gjøre IP-lokalisering vanskeligere, slik at en kan beskytte sin -privatsfære og unngå å dele sin fysiske plassering med -uvedkommede.</p> - -<P>Men det er en ting som bekymrer meg rundt denne nyheten. Jeg ble -tipset (takk #nuug) om -<a href="https://www.nav.no/no/NAV+og+samfunn/Kontakt+NAV/Teknisk+brukerstotte/Snarveier/personvernerkl%C3%A6ring-for-arbeids-og-velferdsetaten">NAVs -personvernerklæring</a>, som under punktet «Personvern og statistikk» -lyder:</p> - -<p><blockquote> - -<p>«Når du besøker nav.no, etterlater du deg elektroniske spor. Sporene -dannes fordi din nettleser automatisk sender en rekke opplysninger til -NAVs tjener (server-maskin) hver gang du ber om å få vist en side. Det -er eksempelvis opplysninger om hvilken nettleser og -versjon du -bruker, og din internettadresse (ip-adresse). For hver side som vises, -lagres følgende opplysninger:</p> - -<ul> -<li>hvilken side du ser på</li> -<li>dato og tid</li> -<li>hvilken nettleser du bruker</li> -<li>din ip-adresse</li> -</ul> - -<p>Ingen av opplysningene vil bli brukt til å identifisere -enkeltpersoner. NAV bruker disse opplysningene til å generere en -samlet statistikk som blant annet viser hvilke sider som er mest -populære. Statistikken er et redskap til å forbedre våre -tjenester.»</p> - -</blockquote></p> - -<p>Jeg klarer ikke helt å se hvordan analyse av de besøkendes -IP-adresser for å se hvem som sender inn meldekort via web fra en -IP-adresse i utlandet kan gjøres uten å komme i strid med påstanden om -at «ingen av opplysningene vil bli brukt til å identifisere -enkeltpersoner». Det virker dermed for meg som at NAV bryter sine -egen personvernerklæring, hvilket -<a href="http://people.skolelinux.org/pere/blog/Er_lover_brutt_n_r_personvernpolicy_ikke_stemmer_med_praksis_.html">Datatilsynet -fortalte meg i starten av desember antagelig er brudd på -personopplysningsloven</a>. - -<p>I tillegg er personvernerklæringen ganske misvisende i og med at -NAVs nettsider ikke bare forsyner NAV med personopplysninger, men i -tillegg ber brukernes nettleser kontakte fem andre nettjenere -(script.hotjar.com, static.hotjar.com, vars.hotjar.com, -www.google-analytics.com og www.googletagmanager.com), slik at -personopplysninger blir gjort tilgjengelig for selskapene Hotjar og -Google , og alle som kan lytte på trafikken på veien (som FRA, GCHQ og -NSA). Jeg klarer heller ikke se hvordan slikt spredning av -personopplysninger kan være i tråd med kravene i -personopplysningloven, eller i tråd med NAVs personvernerklæring.</p> - -<p>Kanskje NAV bør ta en nøye titt på sin personvernerklæring? Eller -kanskje Datatilsynet bør gjøre det?</p> + The worlds only stone power plant? + http://people.skolelinux.org/pere/blog/The_worlds_only_stone_power_plant_.html + http://people.skolelinux.org/pere/blog/The_worlds_only_stone_power_plant_.html + Sat, 30 Jun 2018 10:35:00 +0200 + <p>So far, at least hydro-electric power, coal power, wind power, +solar power, and wood power are well known. Until a few days ago, I +had never heard of stone power. Then I learn about a quarry in a +mountain in +<a href="https://en.wikipedia.org/wiki/Bremanger">Bremanger</a> i +Norway, where +<a href="https://www.bontrup.com/en/activities/raw-materials/bremanger-quarry/">the +Bremanger Quarry</a> company is extracting stone and dumping the stone +into a shaft leading to its shipping harbour. This downward movement +in this shaft is used to produce electricity. In short, it is using +falling rocks instead of falling water to produce electricity, and +according to its own statements it is producing more power than it is +using, and selling the surplus electricity to the Norwegian power +grid. I find the concept truly amazing. Is this the worlds only +stone power plant?</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> - Where did that package go? &mdash; geolocated IP traceroute - http://people.skolelinux.org/pere/blog/Where_did_that_package_go___mdash__geolocated_IP_traceroute.html - http://people.skolelinux.org/pere/blog/Where_did_that_package_go___mdash__geolocated_IP_traceroute.html - Mon, 9 Jan 2017 12:20:00 +0100 - <p>Did you ever wonder where the web trafic really flow to reach the -web servers, and who own the network equipment it is flowing through? -It is possible to get a glimpse of this from using traceroute, but it -is hard to find all the details. Many years ago, I wrote a system to -map the Norwegian Internet (trying to figure out if our plans for a -network game service would get low enough latency, and who we needed -to talk to about setting up game servers close to the users. Back -then I used traceroute output from many locations (I asked my friends -to run a script and send me their traceroute output) to create the -graph and the map. The output from traceroute typically look like -this: - -<p><pre> -traceroute to www.stortinget.no (85.88.67.10), 30 hops max, 60 byte packets - 1 uio-gw10.uio.no (129.240.202.1) 0.447 ms 0.486 ms 0.621 ms - 2 uio-gw8.uio.no (129.240.24.229) 0.467 ms 0.578 ms 0.675 ms - 3 oslo-gw1.uninett.no (128.39.65.17) 0.385 ms 0.373 ms 0.358 ms - 4 te3-1-2.br1.fn3.as2116.net (193.156.90.3) 1.174 ms 1.172 ms 1.153 ms - 5 he16-1-1.cr1.san110.as2116.net (195.0.244.234) 2.627 ms he16-1-1.cr2.oslosda310.as2116.net (195.0.244.48) 3.172 ms he16-1-1.cr1.san110.as2116.net (195.0.244.234) 2.857 ms - 6 ae1.ar8.oslosda310.as2116.net (195.0.242.39) 0.662 ms 0.637 ms ae0.ar8.oslosda310.as2116.net (195.0.242.23) 0.622 ms - 7 89.191.10.146 (89.191.10.146) 0.931 ms 0.917 ms 0.955 ms - 8 * * * - 9 * * * -[...] -</pre></p> - -<p>This show the DNS names and IP addresses of (at least some of the) -network equipment involved in getting the data traffic from me to the -www.stortinget.no server, and how long it took in milliseconds for a -package to reach the equipment and return to me. Three packages are -sent, and some times the packages do not follow the same path. This -is shown for hop 5, where three different IP addresses replied to the -traceroute request.</p> - -<p>There are many ways to measure trace routes. Other good traceroute -implementations I use are traceroute (using ICMP packages) mtr (can do -both ICMP, UDP and TCP) and scapy (python library with ICMP, UDP, TCP -traceroute and a lot of other capabilities). All of them are easily -available in <a href="https://www.debian.org/">Debian</a>.</p> - -<p>This time around, I wanted to know the geographic location of -different route points, to visualize how visiting a web page spread -information about the visit to a lot of servers around the globe. The -background is that a web site today often will ask the browser to get -from many servers the parts (for example HTML, JSON, fonts, -JavaScript, CSS, video) required to display the content. This will -leak information about the visit to those controlling these servers -and anyone able to peek at the data traffic passing by (like your ISP, -the ISPs backbone provider, FRA, GCHQ, NSA and others).</p> - -<p>Lets pick an example, the Norwegian parliament web site -www.stortinget.no. It is read daily by all members of parliament and -their staff, as well as political journalists, activits and many other -citizens of Norway. A visit to the www.stortinget.no web site will -ask your browser to contact 8 other servers: ajax.googleapis.com, -insights.hotjar.com, script.hotjar.com, static.hotjar.com, -stats.g.doubleclick.net, www.google-analytics.com, -www.googletagmanager.com and www.netigate.se. I extracted this by -asking <a href="http://phantomjs.org/">PhantomJS</a> to visit the -Stortinget web page and tell me all the URLs PhantomJS downloaded to -render the page (in HAR format using -<a href="https://github.com/ariya/phantomjs/blob/master/examples/netsniff.js">their -netsniff example</a>. I am very grateful to Gorm for showing me how -to do this). My goal is to visualize network traces to all IP -addresses behind these DNS names, do show where visitors personal -information is spread when visiting the page.</p> - -<p align="center"><a href="www.stortinget.no-geoip.kml"><img -src="http://people.skolelinux.org/pere/blog/images/2017-01-09-www.stortinget.no-geoip-small.png" alt="map of combined traces for URLs used by www.stortinget.no using GeoIP"/></a></p> - -<p>When I had a look around for options, I could not find any good -free software tools to do this, and decided I needed my own traceroute -wrapper outputting KML based on locations looked up using GeoIP. KML -is easy to work with and easy to generate, and understood by several -of the GIS tools I have available. I got good help from by NUUG -colleague Anders Einar with this, and the result can be seen in -<a href="https://github.com/petterreinholdtsen/kmltraceroute">my -kmltraceroute git repository</a>. Unfortunately, the quality of the -free GeoIP databases I could find (and the for-pay databases my -friends had access to) is not up to the task. The IP addresses of -central Internet infrastructure would typically be placed near the -controlling companies main office, and not where the router is really -located, as you can see from <a href="www.stortinget.no-geoip.kml">the -KML file I created</a> using the GeoLite City dataset from MaxMind. - -<p align="center"><a href="http://people.skolelinux.org/pere/blog/images/2017-01-09-www.stortinget.no-scapy.svg"><img -src="http://people.skolelinux.org/pere/blog/images/2017-01-09-www.stortinget.no-scapy-small.png" alt="scapy traceroute graph for URLs used by www.stortinget.no"/></a></p> - -<p>I also had a look at the visual traceroute graph created by -<a href="http://www.secdev.org/projects/scapy/">the scrapy project</a>, -showing IP network ownership (aka AS owner) for the IP address in -question. -<a href="http://people.skolelinux.org/pere/blog/images/2017-01-09-www.stortinget.no-scapy.svg">The -graph display a lot of useful information about the traceroute in SVG -format</a>, and give a good indication on who control the network -equipment involved, but it do not include geolocation. This graph -make it possible to see the information is made available at least for -UNINETT, Catchcom, Stortinget, Nordunet, Google, Amazon, Telia, Level -3 Communications and NetDNA.</p> - -<p align="center"><a href="https://geotraceroute.com/index.php?node=4&host=www.stortinget.no"><img -src="http://people.skolelinux.org/pere/blog/images/2017-01-09-www.stortinget.no-geotraceroute-small.png" alt="example geotraceroute view for www.stortinget.no"/></a></p> - -<p>In the process, I came across the -<a href="https://geotraceroute.com/">web service GeoTraceroute</a> by -Salim Gasmi. Its methology of combining guesses based on DNS names, -various location databases and finally use latecy times to rule out -candidate locations seemed to do a very good job of guessing correct -geolocation. But it could only do one trace at the time, did not have -a sensor in Norway and did not make the geolocations easily available -for postprocessing. So I contacted the developer and asked if he -would be willing to share the code (he refused until he had time to -clean it up), but he was interested in providing the geolocations in a -machine readable format, and willing to set up a sensor in Norway. So -since yesterday, it is possible to run traces from Norway in this -service thanks to a sensor node set up by -<a href="https://www.nuug.no/">the NUUG assosiation</a>, and get the -trace in KML format for further processing.</p> - -<p align="center"><a href="http://people.skolelinux.org/pere/blog/images/2017-01-09-www.stortinget.no-geotraceroute-kml-join.kml"><img -src="http://people.skolelinux.org/pere/blog/images/2017-01-09-www.stortinget.no-geotraceroute-kml-join.png" alt="map of combined traces for URLs used by www.stortinget.no using geotraceroute"/></a></p> - -<p>Here we can see a lot of trafic passes Sweden on its way to -Denmark, Germany, Holland and Ireland. Plenty of places where the -Snowden confirmations verified the traffic is read by various actors -without your best interest as their top priority.</p> - -<p>Combining KML files is trivial using a text editor, so I could loop -over all the hosts behind the urls imported by www.stortinget.no and -ask for the KML file from GeoTraceroute, and create a combined KML -file with all the traces (unfortunately only one of the IP addresses -behind the DNS name is traced this time. To get them all, one would -have to request traces using IP number instead of DNS names from -GeoTraceroute). That might be the next step in this project.</p> - -<p>Armed with these tools, I find it a lot easier to figure out where -the IP traffic moves and who control the boxes involved in moving it. -And every time the link crosses for example the Swedish border, we can -be sure Swedish Signal Intelligence (FRA) is listening, as GCHQ do in -Britain and NSA in USA and cables around the globe. (Hm, what should -we tell them? :) Keep that in mind if you ever send anything -unencrypted over the Internet.</p> - -<p>PS: KML files are drawn using -<a href="http://ivanrublev.me/kml/">the KML viewer from Ivan -Rublev<a/>, as it was less cluttered than the local Linux application -Marble. There are heaps of other options too.</p> + Add-on to control the projector from within Kodi + http://people.skolelinux.org/pere/blog/Add_on_to_control_the_projector_from_within_Kodi.html + http://people.skolelinux.org/pere/blog/Add_on_to_control_the_projector_from_within_Kodi.html + Tue, 26 Jun 2018 23:55:00 +0200 + <p>My movie playing setup involve <a href="https://kodi.tv/">Kodi</a>, +<a href="https://openelec.tv">OpenELEC</a> (probably soon to be +replaced with <a href="https://libreelec.tv/">LibreELEC</a>) and an +Infocus IN76 video projector. My projector can be controlled via both +a infrared remote controller, and a RS-232 serial line. The vendor of +my projector, <a href="https://www.infocus.com/">InFocus</a>, had been +sensible enough to document the serial protocol in its user manual, so +it is easily available, and I used it some years ago to write +<a href="https://github.com/petterreinholdtsen/infocus-projector-control">a +small script to control the projector</a>. For a while now, I longed +for a setup where the projector was controlled by Kodi, for example in +such a way that when the screen saver went on, the projector was +turned off, and when the screen saver exited, the projector was turned +on again.</p> + +<p>A few days ago, with very good help from parts of my family, I +managed to find a Kodi Add-on for controlling a Epson projector, and +got in touch with its author to see if we could join forces and make a +Add-on with support for several projectors. To my pleasure, he was +positive to the idea, and we set out to add InFocus support to his +add-on, and make the add-on suitable for the official Kodi add-on +repository.</p> + +<p>The Add-on is now working (for me, at least), with a few minor +adjustments. The most important change I do relative to the master +branch in the github repository is embedding the +<a href="https://github.com/pyserial/pyserial">pyserial module</a> in +the add-on. The long term solution is to make a "script" type +pyserial module for Kodi, that can be pulled in as a dependency in +Kodi. But until that in place, I embed it.</p> + +<p>The add-on can be configured to turn on the projector when Kodi +starts, off when Kodi stops as well as turn the projector off when the +screensaver start and on when the screesaver stops. It can also be +told to set the projector source when turning on the projector. + +<p>If this sound interesting to you, check out +<a href="https://github.com/fredrik-eriksson/kodi_projcontrol">the +project github repository</a>. Perhaps you can send patches to +support your projector too? As soon as we find time to wrap up the +latest changes, it should be available for easy installation using any +Kodi instance.</p> + +<p>For future improvements, I would like to add projector model +detection and the ability to adjust the brightness level of the +projector from within Kodi. We also need to figure out how to handle +the cooling period of the projector. My projector refuses to turn on +for 60 seconds after it was turned off. This is not handled well by +the add-on at the moment.</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&label=PetterReinholdtsenBlog">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p> +<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>