Search Results: "Andreas Henriksson"

2 October 2017

James McCoy: Monthly FLOSS activity - 2017/09 edition

Debian devscripts Before deciding to take an indefinite hiatus from devscripts, I prepared one more upload merging various contributed patches and a bit of last minute cleanup. I also setup integration with Travis CI to hopefully catch issues sooner than "while preparing an upload", as was typically the case before. Anyone with push access to the Debian/devscripts GitHub repo can take advantage of this to test out changes, or keep the development branches up to date. In the process, I was able to make some improvements to, namely support for DEB_BUILD_PROFILES and using a separate, minimal docker image for running autopkgtests. unibilium neovim Oddly, the mips64el builds were in BD-Uninstallable state, even though luajit's buildd status showed it was built. Looking further, I noticed the libluajit-5.1 ,-dev binary packages didn't have the mips64el architecture enabled, so I asked for it to be enabled. msgpack-c There were a few packages left which would FTBFS if I uploaded msgpack-c 2.x to unstable. All of the bug reports had either trivial work arounds (i.e., forcing use of the v1 C++ API) or trivial patches. However, I didn't want to continue waiting for the packages to get fixed since I knew other people had expressed interest in the new msgpack-c. Trying to avoid making other packages insta-buggy, I NMUed autobahn-cpp with the v1 work around. That didn't go over well, partly because I didn't send a finalized "Hey, I'd like to get this done and here's my plan to NMU" email. Based on that feedback, I decided to bump the remaining bugs to "serious" instead of NMUing and upload msgpack-c. Thanks to Jonas Smedegaard for quickly integrating my proposed fix for libdata-messagepack-perl. Hopefully, upstream has some time to review the PR soon. vim subversion

20 September 2016

Reproducible builds folks: Reproducible Builds: week 73 in Stretch cycle

What happened in the Reproducible Builds effort between Sunday September 11 and Saturday September 17 2016: Toolchain developments Ximin Luo started a new series of tools called (for now) debrepatch, to make it easier to automate checks that our old patches to Debian packages still apply to newer versions of those packages, and still make these reproducible. Ximin Luo updated one of our few remaining patches for dpkg in #787980 to make it cleaner and more minimal. The following tools were fixed to produce reproducible output: Packages reviewed and fixed, and bugs filed The following updated packages have become reproducible - in our current test setup - after being fixed: The following updated packages appear to be reproducible now, for reasons we were not able to figure out. (Relevant changelogs did not mention reproducible builds.) The following 3 packages were not changed, but have become reproducible due to changes in their build-dependencies: jaxrs-api python-lua zope-mysqlda. Some uploads have addressed some reproducibility issues, but not all of them: Patches submitted that have not made their way to the archive yet: Reviews of unreproducible packages 462 package reviews have been added, 524 have been updated and 166 have been removed in this week, adding to our knowledge about identified issues. 25 issue types have been updated: Weekly QA work FTBFS bugs have been reported by: diffoscope development A new version of diffoscope 60 was uploaded to unstable by Mattia Rizzolo. It included contributions from: It also included from changes previous weeks; see either the changes or commits linked above, or previous blog posts 72 71 70. strip-nondeterminism development New versions of strip-nondeterminism 0.027-1 and 0.028-1 were uploaded to unstable by Chris Lamb. It included contributions from: disorderfs development A new version of disorderfs 0.5.1 was uploaded to unstable by Chris Lamb. It included contributions from: It also included from changes previous weeks; see either the changes or commits linked above, or previous blog posts 70. Misc. This week's edition was written by Ximin Luo and reviewed by a bunch of Reproducible Builds folks on IRC.

2 May 2016

Reproducible builds folks: Reproducible builds: week 53 in Stretch cycle

What happened in the Reproducible Builds effort between April 24th and 30th 2016. Media coverage Reproducible builds were mentioned explicitly in two talks at the Mini-DebConf in Vienna: Aspiration together with the OTF CommunityLab released their report about the Reproducible Builds summit in December 2015 in Athens. Toolchain fixes Now that the GCC development window has been opened again, the SOURCE_DATE_EPOCH patch by Dhole and Matthias Klose to address the issue timestamps_from_cpp_macros (__DATE__ / __TIME__) has been applied upstream and will be released with GCC 7. Following that Matthias Klose also has uploaded gcc-5/5.3.1-17 and gcc-6/6.1.1-1 to unstable with a backport of that SOURCE_DATE_EPOCH patch. Emmanuel Bourg uploaded maven/3.3.9-4, which uses SOURCE_DATE_EPOCH for the (SOURCE_DATE_EPOCH specification) Other upstream changes Alexis Bienven e submitted a patch to Sphinx which extends SOURCE_DATE_EPOCH support for copyright years in generated documentation. Packages fixed The following 12 packages have become reproducible due to changes in their build dependencies: hhvm jcsp libfann libflexdock-java libjcommon-java libswingx1-java mobile-atlas-creator not-yet-commons-ssl plexus-utils squareness svnclientadapter The following packages have became reproducible after being fixed: Some uploads have fixed some reproducibility issues, but not all of them: Patches submitted that have not made their way to the archive yet: Package reviews 95 reviews have been added, 15 have been updated and 129 have been removed in this week. 22 FTBFS bugs have been reported by Chris Lamb and Martin Michlmayr. diffoscope development strip-nondeterminism development Misc. Amongst the 29 interns who will work on Debian through GSoC and Outreachy there are four who will be contributing to Reproducible Builds for Debian and Free Software. We are very glad to welcome ceridwen, Satyam Zode, Scarlett Clark and Valerie Young and look forward to working together with them the coming months (and maybe beyond)! This week's edition was written by Reiner Herrmann and Holger Levsen and reviewed by a bunch of Reproducible builds folks on IRC.

4 April 2016

Raphaël Hertzog: My Free Software Activities in February and March 2016

My monthly report covers a large part of what I have been doing in the free software world. I write it for my donators (thanks to them!) but also for the wider Debian community because it can give ideas to newcomers and it s one of the best ways to find volunteers to work with me on projects that matter to me. I skipped my monthly report last time so this one will cover two months. I will try to list only the most important things to not make it too long.  The Debian Handbook I worked with Ryuunosuke Ayanokouzi to prepare a paperback version of the Japanese translation of my book. Thanks to the efforts of everybody, it s now available. Unfortunately, Lulu declined to take it in distribution program so it won t be available on traditional bookstores (like Amazon, etc.). The reason is that they do not support non-latin character sets in the meta-data. I tried to cheat a little bit by inputting the description in English (still explaining that the book was in Japanese) but they rejected it nevertheless because the English title could mislead people. So the paperback is only available on Fortunately, the shipping costs are reasonable if you pick the most economic offer. Following this I invited the Italian, Spanish and Brazilian Portuguese translators to complete the work (they were close will all the strings already translated, mainly missing translated screenshots and some backcover content) so that we can also release paperback versions in those languages. It s getting close to completion for them. Hopefully we will have those available until next month. Distro Tracker In early February, I tweaked the configuration to send (by email) exceptions generated by incoming mails and by routine task. Before this they were logged but I did not take the time to look into them. This quickly brought a few issues into light and I fixed them as they appeared: for instance the bounce handling code was getting confused when the character case was not respected, and it appears that some emails come back to us after having been lowercased. Also the code was broken when the References field used more than one line on incoming control emails. This brought into light a whole class of problems with the database storing twice the same email with only differing case. So I did further work to merge all those duplicate entries behind a single email entry. Later, the experimental Sources files changed and I had to tweak the code to work with the removal of the Files field (relying instead on Checksums-* to find out the various files part of the entry). At some point, I also fixed the login form to not generate an exception when the user submits an empty form. I also decided that I no longer wanted to support Django 1.7 in distro tracker as Django 1.8 is the current LTS version. I asked the Debian system administrators to update the package on with the version in jessie-backports. This allowed me to fix a few deprecation warnings that I kept triggering because I wanted the code to work with Django 1.7. One of those warnings was generated by django-jsonfield though and I could not fix it immediately. Instead I prepared a pull request that I submitted to the upstream author. Oh, and a last thing, I tweaked the CSS to densify the layout on the package page. This was one of the most requested changes from the people who were still preferring over Kali and new pkg-security team As part of my Kali work, I have been fixing RC bugs in Debian packages that we use in Kali. But in many cases, I stumbled upon packages whose maintainers were really missing in action (MIA). Up to now, we were only doing non-maintainers upload (NMU) but I want to be able to maintain those packages more effectively so we created a new pkg-security team (we re only two right now and we have no documentation yet, but if you want to join, you re welcome, in particular if you maintain a package which is useful in the security field). arm64 work. The first 3 packages that we took over (ssldump, sucrack, xprobe) are actually packages that were missing arm64 builds. We just started our arm64 port on Kali and we fixed them for that architecture. Since they were no longer properly maintained, in most cases it was just a matter of using dh_autoreconf to get up-to-date config. sub,guess files. We still miss a few packages on arm64: vboot-utils (that we will likely take over soon since it s offered for adoption), ruby-libv8 and ruby-therubyracer, ntopng (we have to wait a new luajit which is only in experimental right now). We also noticed that dh-make-golang was not available on arm64, after some discussion on #debian-buildd, I filed two bugs for this: #819472 on dh-make-golang and #819473 on dh-golang. RC bug fixing. hdparm was affected by multiple RC bugs and the release managers were trying to get rid of it from testing. This removed multiple packages that were used by Kali and its users. So I investigated the situation of that package, convinced the current maintainers to orphan it, asked for new maintainers on debian-devel, reviewed multiple updates prepared by the new volunteers and sponsored their work. Now hdparm is again RC-bug free and has the latest upstream version. We also updated jsonpickle to 0.9.3-1 to fix RC bug #812114 (that I forwarded upstream first). Systemd presets support in init-system-helpers. I tried to find someone (to hire) to implement the system preset feature I requested in #772555 but I failed. Still Andreas Henriksson was kind enough to give it a try and sent a first patch. I tried it and found some issues so I continued to improve it and simplify it I submitted an updated patch and pinged Martin Pitt. He pointed me to the DEP-8 test failures that my patch was creating. I quickly fixed those afterwards. This patch is in use in Kali and lets us disable network services by default. I would like to see it merged in Debian so that everybody can setup systemd preset file and have their desire respected at installation time. Misc bug reports. I filed #813801 to request a new upstream release of kismet. Same for masscan in #816644 and for wkhtmltopdf in #816714. We packaged (before Debian) a new upstream release of ruby-msgpack and found out that it was not building on armel/armhf so we filed two upstream tickets (with a suggested fix). In #814805, we asked the pyscard maintainer to reinstate python-pyscard that was dropped (keeping only the Python3 version) as we use the Python 2 version in Kali. And there s more: I filed #816553 (segfault) and #816554 against cdebootstrap. I asked for dh-python to have a better behaviour after having being bitten by the fact that dh with python3 was not doing what I expected it to do (see #818175). And I reported #818907 against live-build since it is failing to handle a package whose name contains an upper case character (it s not policy compliant but dpkg supports them). Misc packaging I uploaded Django 1.9.2 to unstable and 1.8.9 to jessie-backports. I provided the supplementary information that Julien Cristau asked me in #807654 but despite this, this jessie update has been ignored for the second point release in a row. It is now outdated until I update it to include the security fixes that have been released in the mean time but I m not yet sure that I will do it the lack of cooperation of the release team for that kind of request is discouraging. I sponsored multiple uploads of dolibarr (on security update notably) and tcpdf (to fix one RC bug). Thanks See you next month for a new summary of my activities.

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15 November 2015

Lunar: Reproducible builds: week 29 in Stretch cycle

What happened in the reproducible builds effort this week: Toolchain fixes Emmanuel Bourg uploaded eigenbase-resgen/ which uses of the scm-safe comment style by default to make them deterministic. Mattia Rizzolo started a new thread on debian-devel to ask a wider audience for issues about the -Wdate-time compile time flag. When enabled, GCC and clang print warnings when __DATE__, __TIME__, or __TIMESTAMP__ are used. Having the flag set by default would prompt maintainers to remove these source of unreproducibility from the sources. Packages fixed The following packages have become reproducible due to changes in their build dependencies: bmake, cyrus-imapd-2.4, drobo-utils, eigenbase-farrago, fhist, fstrcmp, git-dpm, intercal, libexplain, libtemplates-parser, mcl, openimageio, pcal, powstatd, ruby-aggregate, ruby-archive-tar-minitar, ruby-bert, ruby-dbd-odbc, ruby-dbd-pg, ruby-extendmatrix, ruby-rack-mobile-detect, ruby-remcached, ruby-stomp, ruby-test-declarative, ruby-wirble, vtprint. The following packages became reproducible after getting fixed: Some uploads fixed some reproducibility issues, but not all of them: Patches submitted which have not made their way to the archive yet: The fifth and sixth armhf build nodes have been set up, resulting in five more builder jobs for armhf. More than 10,000 packages have now been identified as reproducible with the reproducible toolchain on armhf. (Vagrant Cascadian, h01ger) Helmut Grohne and Mattia Rizzolo now have root access on all 12 build nodes used by and (h01ger) is now linked from all package pages and the dashboard. (h01ger) profitbricks-build5-amd64 and profitbricks-build6-amd64, responsible for running amd64 tests now run 398.26 days in the future. This means that one of the two builds that are being compared will be run on a different minute, hour, day, month, and year. This is not yet the case for armhf. FreeBSD tests are also done with 398.26 days difference. (h01ger) The design of the Arch Linux test page has been greatly improved. (Levente Polyak) diffoscope development Three releases of diffoscope happened this week numbered 39 to 41. It includes support for EPUB files (Reiner Herrmann) and Free Pascal unit files, usually having .ppu as extension (Paul Gevers). The rest of the changes were mostly targetting at making it easier to run diffoscope on other systems. The tlsh, rpm, and debian modules are now all optional. The test suite will properly skip tests that need optional tools or modules when they are not available. As a result, diffosope is now available on PyPI and thanks to the work of Levente Polyak in Arch Linux. Getting these versions in Debian was a bit cumbersome. Version 39 was uploaded with an expired key (according to the keyring on which will hopefully be updated soon) which is currently handled by keeping the files in the queue without REJECTing them. This prevented any other Debian Developpers to upload the same version. Version 40 was uploaded as a source-only upload but failed to build from source which had the undesirable side effect of removing the previous version from unstable. The package faild to build from source because it was built passing -I to debbuild. This excluded the ELF object files and static archives used by the test suite from the archive, preventing the test suite to work correctly. Hopefully, in a nearby future it will be possible to implement a sanity check to prevent such mistakes in the future. It has also been identified that ppudump outputs time in the system timezone without considering the TZ environment variable. Zachary Vance and Paul Gevers raised the issue on the appropriate channels. strip-nondeterminism development Chris Lamb released strip-nondeterminism version 0.014-1 which disables stripping Mono binaries as it is too aggressive and the source of the problem is being worked on by Mono upstream. Package reviews 133 reviews have been removed, 115 added and 103 updated this week. Chris West and Chris Lamb reported 57 new FTBFS bugs. Misc. The video of h01ger and Chris Lamb's talk at MiniDebConf Cambridge is now available. h01ger gave a talk at CCC Hamburg on November 13th, which was well received and sparked some interest among Gentoo folks. Slides and video should be available shortly. Frederick Kautz has started to revive Dhiru Kholia's work on testing Fedora packages. Your editor wish to once again thank #debian-reproducible regulars for reviewing these reports weeks after weeks.

29 June 2015

Lunar: Reproducible builds: week 9 in Stretch cycle

What happened about the reproducible builds effort this week: Toolchain fixes Norbert Preining uploaded texinfo/6.0.0.dfsg.1-2 which makes texinfo indices reproducible. Original patch by Chris Lamb. Lunar submitted recently rebased patches to make the file order of files inside .deb stable. akira filled #789843 to make tex4ht stop printing timestamps in its HTML output by default. Dhole wrote a patch for xutils-dev to prevent timestamps when creating gzip compresed files. Reiner Herrmann sent a follow-up patch for wheel to use UTC as timezone when outputing timestamps. Mattia Rizzolo started a discussion regarding the failure to build from source of subversion when -Wdate-time is added to CPPFLAGS which happens when asking dpkg-buildflags to use the reproducible profile. SWIG errors out because it doesn't recognize the aforementioned flag. Trying to get the .buildinfo specification to more definitive state, Lunar started a discussion on storing the checksums of the binary package used in dpkg status database. akira discovered while proposing a fix for simgrid that CMake internal command to create tarballs would record a timestamp in the gzip header. A way to prevent it is to use the GZIP environment variable to ask gzip not to store timestamps, but this will soon become unsupported. It's up for discussion if the best place to fix the problem would be to fix it for all CMake users at once. Infrastructure-related work Andreas Henriksson did a delayed NMU upload of pbuilder which adds minimal support for build profiles and includes several fixes from Mattia Rizzolo affecting reproducibility tests. Neils Thykier uploaded lintian which both raises the severity of package-contains-timestamped-gzip and avoids false positives for this tag (thanks to Tomasz Buchert). Petter Reinholdtsen filled #789761 suggesting that how-can-i-help should prompt its users about fixing reproducibility issues. Packages fixed The following packages became reproducible due to changes in their build dependencies: autorun4linuxcd, libwildmagic, lifelines, plexus-i18n, texlive-base, texlive-extra, texlive-lang. The following packages became reproducible after getting fixed: Some uploads fixed some reproducibility issues but not all of them: Untested uploaded as they are not in main: Patches submitted which have not made their way to the archive yet: debbindiff development debbindiff/23 includes a few bugfixes by Helmut Grohne that result in a significant speedup (especially on larger files). It used to exhibit the quadratic time string concatenation antipattern. Version 24 was released on June 23rd in a hurry to fix an undefined variable introduced in the previous version. (Reiner Herrmann) debbindiff now has a test suite! It is written using the PyTest framework (thanks Isis Lovecruft for the suggestion). The current focus has been on the comparators, and we are now at 93% of code coverage for these modules. Several problems were identified and fixed in the process: paths appearing in output of javap, readelf, objdump, zipinfo, unsqusahfs; useless MD5 checksum and last modified date in javap output; bad handling of charsets in PO files; the destination path for gzip compressed files not ending in .gz; only metadata of cpio archives were actually compared. stat output was further trimmed to make directory comparison more useful. Having the test suite enabled a refactoring of how comparators were written, switching from a forest of differences to a single tree. This helped removing dust from the oldest parts of the code. Together with some other small changes, version 25 was released on June 27th. A follow up release was made the next day to fix a hole in the test suite and the resulting unidentified leftover from the comparator refactoring. (Lunar) Documentation update Ximin Luo improved code examples for some proposed environment variables for reference timestamps. Dhole added an example on how to fix timestamps C pre-processor macros by adding a way to set the build date externally. akira documented her fix for tex4ht timestamps. Package reviews 94 obsolete reviews have been removed, 330 added and 153 updated this week. Hats off for Chris West (Faux) who investigated many fail to build from source issues and reported the relevant bugs. Slight improvements were made to the scripts for editing the review database, edit-notes and clean-notes. (Mattia Rizzolo) Meetings A meeting was held on June 23rd. Minutes are available. The next meeting will happen on Tuesday 2015-07-07 at 17:00 UTC. Misc. The Linux Foundation announced that it was funding the work of Lunar and h01ger on reproducible builds in Debian and other distributions. This was further relayed in a Bits from Debian blog post.

22 June 2015

Lunar: Reproducible builds: week 8 in Stretch cycle

What happened about the reproducible builds effort this week: Toolchain fixes Andreas Henriksson has improved Johannes Schauer initial patch for pbuilder adding support for build profiles. Packages fixed The following 12 packages became reproducible due to changes in their build dependencies: collabtive, eric, file-rc, form-history-control, freehep-chartableconverter-plugin , jenkins-winstone, junit, librelaxng-datatype-java, libwildmagic, lightbeam, puppet-lint, tabble. The following packages became reproducible after getting fixed: Some uploads fixed some reproducibility issues but not all of them: Patches submitted which have not made their way to the archive yet: Bugs with the ftbfs usertag are now visible on the bug graphs. This explain the recent spike. (h01ger) Andreas Beckmann suggested a way to test building packages using the funny paths that one can get when they contain the full Debian package version string. debbindiff development Lunar started an important refactoring introducing abstactions for containers and files in order to make file type identification more flexible, enabling fuzzy matching, and allowing parallel processing. Documentation update Ximin Luo detailed the proposal to standardize environment variables to pass a reference source date to tools that needs one (e.g. documentation generator). Package reviews 41 obsolete reviews have been removed, 168 added and 36 updated this week. Some more issues affecting packages failing to build from source have been identified. Meetings Minutes have been posted for Tuesday June 16th meeting. The next meeting is scheduled Tuesday June 23rd at 17:00 UTC. Presentations Lunar presented the project in French during Pas Sage en Seine in Paris. Video and slides are available.

20 June 2015

Lunar: Reproducible builds: week 4 in Stretch cycle

What happened about the reproducible builds effort for this week: Toolchain fixes Lunar rebased our custom dpkg on the new release, removing a now unneeded patch identified by Guillem Jover. An extra sort in the buildinfo generator prevented a stable order and was quickly fixed once identified. Mattia Rizzolo also rebased our custom debhelper on the latest release. Packages fixed The following 30 packages became reproducible due to changes in their build dependencies: animal-sniffer, asciidoctor, autodock-vina, camping, cookie-monster, downthemall, flashblock, gamera, httpcomponents-core, https-finder, icedove-l10n, istack-commons, jdeb, libmodule-build-perl, libur-perl, livehttpheaders, maven-dependency-plugin, maven-ejb-plugin, mozilla-noscript, nosquint, requestpolicy, ruby-benchmark-ips, ruby-benchmark-suite, ruby-expression-parser, ruby-github-markup, ruby-http-connection, ruby-settingslogic, ruby-uuidtools, webkit2gtk, wot. The following packages became reproducible after getting fixed: Some uploads fixed some reproducibility issues but not all of them: Patches submitted which did not make their way to the archive yet: Also, the following bugs have been reported: Holger Levsen made several small bug fixes and a few more visible changes: strip-nondeterminism Version 0.007-1 of strip-nondeterminism the tool to post-process various file formats to normalize them has been uploaded by Holger Levsen. Version 0.006-1 was already in the reproducible repository, the new version mainly improve the detection of Maven's files. debbindiff development At the request of Emmanuel Bourg, Reiner Herrmann added a comparator for Java .class files. Documentation update Christoph Berg created a new page for the timestamps in manpages created by Doxygen. Package reviews 93 obsolete reviews have been removed, 76 added and 43 updated this week. New identified issues: timestamps in manpages generated by Doxygen, modification time differences in files extracted by unzip, tstamp task used in Ant build.xml, timestamps in documentation generated by ASDocGen. The description for build id related issues has been clarified. Meetings Holger Levsen announced a first meeting on Wednesday, June 3rd, 2015, 19:00 UTC. The agenda is amendable on the wiki. Misc. Lunar worked on a proof-of-concept script to import the build environment found in .buildinfo files to UDD. Lucas Nussbaum has positively reviewed the proposed schema. Holger Levsen cleaned up various experimental toolchain repositories, marking merged brances as such.

8 April 2010

Stefano Zacchiroli: RC bugs of the week - issue 26

RCBW - #26 RC bug count: 666 It is getting down, even though the current number is scary. My personal RC bug count is not so mystical and as low as 205 RC bugs to go, which is quite encouraging. Without any further ado, here are this week squashes: Random points:

19 June 2008

Martin F. Krafft: IPv6 with Debian

Even though I ve dealt with IPv6 for almost a decade, have delivered presentations, and given multi-day courses on IPv6 security aspects, I ve never actually added IPv6 to my own server/home network infrastructure because it seemed that Linux and/or Debian just weren t ready for it. This seems to have changed (although there are still a number of problems) and in less than a day, I put a few of my machines online. In the following, I d like to share with you how I did it.

Kernel versions and stateful connection tracking Unfortunately, I have to start off with some bad news: even though Debian etch, our current stable release, which uses a Linux kernel version 2.6.18, speaks IPv6, I cannot recommend it for deployment, as the 2.6.18 kernel does not support proper stateful connection tracking for IPv6, and thus makes it impossible to firewall hosts in a sensible manner (I always add local packet filters to all my hosts, and if only to guard against the situation when a user installs a malicious programme to listen on a high port). Of course, it is possible to configure a packet filter statelessly in an acceptable manner once you know the use case, so do with this information what you wish; I prefer to stay general for now. For me, a remedy is almost around the corner: the 2.6.24 kernel seems to support stateful connection tracking for IPv6, and it s even available for etch as it will be included in the upcoming etch-and-a-half release. I simply ended up using the kernel packages pre-release, and so far have not had a problem with it. To do so, add the following line to your /etc/apt/sources.list, making sure to use a close archive mirror:
deb etch-proposed-updates main

I then just upgraded the system and pulled in all proposed updates. As that may have let in software that won t be part of etch-and-a-half, or even lenny, you may want to pin the archive and only upgrade the kernel packages, by adding to /etc/apt/preferences (replacing amd64 with your architecture):
Package: *
Pin: release a=proposed-updates
Pin-Priority: -1
Package: linux-image-2.6.24-etchnhalf.1-amd64
Pin: release a=proposed-updates
Pin-Priority: 600

Alternatively, you could use the 2.6.24 linux kernel packages on

Xen and IPv6 One drawback of switching to 2.6.24 is that you cannot run a dom0 on that machine any longer, so by practical extension, you cannot connect it to the IPv6 network with a packet filter in place. Supposedly, running 2.6.24 instances on a 2.6.18 dom0 is reported to work, however.

Configuring the packet filter The first thing I did was to configure the packet filter on each host appropriately. Unfortunately, this is harder than it should be, because to quote one of the netfilter developers when ip6tables was conceived, someone had a big bad brainfart : rather than adding IPv6 rules to your existing iptables ruleset, you have to create a new ruleset, duplicate all chains, networks, hosts, and individual rules, and maintain the two in parallel. Even though there are efforts of unification on the way, I speculate it ll take another couple of years until PF_INET6 will be fused into PF_INET and one will be able to do sensible cross-address-family packet filtering with Linux. Since I ve recently started to look (again) at pyroman, maybe the most logical way forward would be to extend it to write both, IPv4 and IPv6 rulesets from its knowledge about the hosts and networks you configured. Anyway, we want to get stuff working now! Thus, let s configure ourselves a packet filter. (Almost) all IPv6-related filtering must be configured via ip6tables (read on further down about IPv6 in IPv4 tunneling, the reason I said almost ). The following is a simple default ruleset to start with, which I put into /etc/network/ip6tables to load with ip6tables-restore:
:in-new - [0:0]
### INPUT chain
# allow all loopback traffic
-A INPUT -i lo -j ACCEPT
# RT0 processing is disabled since
#-A INPUT -m rt --rt-type 0 -j REJECT
# allow all ICMP traffic
-A INPUT -p icmpv6 -j ACCEPT
# packets belonging to an establish connection or related to one can pass
# packets that are out-of-sequence are silently dropped
-A INPUT -m state --state INVALID -j DROP
# new connections unknown to the kernel are handled in a separate chain
-A INPUT -m state --state NEW -j in-new
# pass SYN packets for SSH
-A in-new -p tcp -m tcp --dport 22 --syn -j ACCEPT
# log everything else
-A INPUT -m limit --limit 3/min --limit-burst 10 -j LOG --log-prefix "[INPUT6]: "
### OUTPUT chain
# RT0 processing is disabled since
#-A OUTPUT -m rt --rt-type 0 -j REJECT
# allow outgoing traffic, explicitly (despite chain policy)
### FORWARD chain
# RT0 processing is disabled since
#-A FORWARD -m rt --rt-type 0 -j REJECT
# disallow forwarded traffic, explicitly (despite chain policy)

Note that this recipe is pretty much unusable on pre-2.6.20 kernels due to their broken implementation of stateful connection tracking. The ruleset should be fairly obvious, but you might wonder about my use of REJECT and allowing all ICMP after all, you ve heard for the past 30 years that ICMP is a bad hacker protocol , and Internet security is no domain for being nice to people, so to prevent any information disclosure, you should DROP connections, not let people know that they re simply not allowed. Well, to hell with all that! I don t see a single reason or attack vector that is foiled by DROP or disallowing ICMP. In fact, it s just security by obscurity, and might inconvenient at the same time. ICMP is also much more important with IPv6 than with IPv4 (it replaces ARP, for instance), and it s actually useful to be able to ping hosts, or get back informational messages on why something failed. Finally, rejecting traffic rather than dropping it doesn t suggest to a hacker that something s hidden here. Then there is RFC 4890, which almost made me puke. This document is part of the reason why I say: let s fix problems in the kernel, rather than shielding them with unreadable and unmanageable rulesets!

Getting connected If you already have an IPv6 address, you re basically ready to go, but may want to read further down on how to connect your local network to the IPv6 Internet as well. If you are searching for a provider, have a look at the list of providers with native IPv6 connectivity over at If you are reading up to here, I assume you are connected to the Net with IPv4. There are two ways for you to move towards IPv6: 6to4 or by way of a tunnel provider. A Kiwi website explains how to setting up 6to4 connectivity, and thus I will concentrate only on the tunnel approach. Even though everyone can set up 6to4 in a breeze without any accounts or waiting, there are a number of security considerations, it s pretty ugly to debug (due in part to asymmetric routing), and makes your life unnecessarily difficult when all you have is a dynamic IP that changes from time to time. If you are stuck behind a NAT gateway, you cannot use 6to4 either. Thus, I prefer the tunnel approach. With the tunnel approach, IPv6 packets are wrapped up in IPv4 packets on your host, and sent to the IPv4 address of your tunnel provider, who has native IPv6 connectivity. The tunnel provider unwraps your packet and shoves the contained IPv6 packet onto the backbone. The IPv6 address you used as source address is routed to the tunnel provider, so any replies arrive at their machines, where they re again wrapped into IPv4 packets and sent to your (publicly-accessible) IPv4 address. Those IPv4 packets specify payload type 41 ( ipv6 ), which is why we need those -p ipv6 -j ACCEPT rules in the iptables ruleset. There are a few tunnel providers out there. I chose SixXS and have not regretted my choice. I shall thus assume that you do the same: sign up for an account right now, so that you have it by the time you finished reading this document! SixXS works on a credit system: tunnels and subnets cost credits, which you can accumulate by maintaining your tunnels properly. This ensures that everyone can play around, but to do more advanced stuff, you need to first display competence with the basic concepts. Your first step with SixXS will be to request a tunnel. SixXS offers three types of tunnels:
  • static tunnels, for those with static IPs,
  • heartbeat tunnels, for those with dynamic IPs, and
  • AYIYA tunnels, for those behind NAT gateways.
Each of these tunnels have advantages and disadvantages, as everything does: the first two types of tunnels use IP protocol 41 packets to encapsulate the IPv6 packets. As such, there are security considerations involving the impersonation by spoofing, and all upstream firewalls must let protocol 41 pass. AYIYA addresses these problems by using signed packets, but that solution comes with extra computation overhead and smaller MTUs. I suggest to use the first type of tunnel that fits your situation. Debian s aiccu package can take care of heartbeat and AYIYA tunnels for you, and it can even set up static ones. During registration, you will also need to choose a PoP , which stands for Point of Presence . If your country only has a single PoP, that s the one you will end up using (unless you have a good reason for another one), but if there are more options, I strongly suggest that you go through the list of PoPs and select the one with the best roundtrip time and lowest latency from your location! Note that you must answer ping requests (ICMP echo-request) from the PoP you chose, or else the tunnel will not be created. Once your tunnel request gets approved, you ll get a /64 prefix, in which you only use two addresses: the PoP will configure the :1 address and you need to configure your host to use the :2 address on the tunnel interface. You ll also be told the IPv4 address of your PoP endpoint . Joey Hess taught me that aiccu can set up the interface for you, using the data it queries from the SixXS registration (TIC) server. I tried it, and it works. However, I prefer the pure ifupdown approach, as it makes things explicit and allows me to use the hooks for stuff like loading the packet filter. So in my /etc/network/interfaces, you can find:
auto sixxs
iface sixxs inet6 v4tunnel
  address 2001:41e0:ff00:3b::2
  netmask 64
  gateway 2001:41e0:ff00:3b::1
  ttl 64
  pre-up ip6tables-restore < /etc/network/ip6tables
  up ip link set mtu 1480 dev $IFACE
  up invoke-rc.d aiccu start
  down invoke-rc.d aiccu stop

Make sure to read about MTU values of the tunnel and adjust the 1480 value in the above to your tunnel settings and ISP connectivity. Also set ipv6_interface sixxs in /etc/aiccu.conf, if you are using aiccu, or else aiccu will bring up a duplicate/additional interface. If you tell it to use the same interface, it will actually execute all the same commands (which will fail), but won t report any errors. A future version will have a switch to prevent it from configuring the interface. Unfortunately, this will probably not work. The reason is that your regular IP packet filter (iptables, without the 6) doesn t let those encapsulating IPv4 packets pass, unless we tell it to; we probably want to do this early on in the chain, and also limit it to our tunnel peer, so:
iptables -I INPUT -p ipv6 -s -j ACCEPT

For AYIYA, you need to open port 5072, either for UDP, TCP, or SCTP, depending on how you configured it. Also have a look at this FAQ entry on what a firewall needs to pass. If it still doesn t work, you have an upstream packet filter that needs some of those holes poked. Good luck. In most situations, the FORWARD chain does not get such a rule, since the tunnel terminates at the gateway, which routes to a native IPv6 network, or another tunnel. Allowing tunnels through a gateway is almost always a bad thing, as it would allow undetected and untraceable traffic from compromised boxes in the local network. The OUTPUT chain also does not need such a rule, if you have configured stateful filtering properly. Now bring up the interface and verify the connection:
# ifup sixxs
# ping6 -nc1 2001:41e0:ff00:3b::1
PING 2001:41e0:ff00:3b::1(2001:41e0:ff00:3b::1) 56 data bytes
64 bytes from 2001:41e0:ff00:3b::1: icmp_seq=1 ttl=64 time=74.0 ms
# ping6 -nc1
PING 56 data bytes
64 bytes from 2001:a60:9002:1::184:1: icmp_seq=1 ttl=55 time=91.5 ms

Welcome to the Internet of the future!

Setting up an IPv6-capable gateway Your IPv6 connection works, but it s limited to a single address, and you do not get to specify the reverse DNS PTR record for it. Since the concept of NAT is mostly absent from IPv6 (thanks! thanks! thanks!), you will not be able to connect any other hosts to the IPv6 network. If your local network has a few hosts behind a gateway, you will need to request a subnet from SixXS and configure your gateway (which has the tunnel connection) appropriately. Don t worry, this is not really very difficult. First, request a subnet for your tunnel from your PoP via your SixXS homepage. Once approved, you will get a /48 prefix for your own use: 2^80 1.2 heptillion addresses which are yours to assign to every dust particle in your office or home, if you so desire. The way I set it up is to add the first of these addresses to your internal interface on the gateway, by adding the following two lines to the interface s stanza in /etc/network/interfaces; you will need the iproute package installed (which you should be using for everything network-related anyway):
up ip -6 addr add 2001:41e0:ff12::1/64 dev $IFACE
down ip -6 addr del 2001:41e0:ff12::1/64 dev $IFACE

Instead of bringing the interface down and up, just run ip -6 addr add 2001:41e0:ff12::1/64 dev eth0. Note the use of the /64 prefix instead of the /48 that got assigned, leaving only 20 pentillion addresses. Oh no! The reason for this is buried in the specs: basically, /48 is a site prefix, but individual networks should not be larger than /64, which is the prefix length of links in the IPv6 domain. Now is also a good time to enable IPv6 forwarding, e.g. like so:
# echo net.ipv6.conf.all.forwarding = 1 >> /etc/sysctl.conf
# sysctl -p /etc/sysctl.conf

Obviously, you will also need to change the policy on the ip6tables FORWARD chain. For now, let s just set it to accept. You should later create a proper ruleset, though!
# ip6tables -I FORWARD -j ACCEPT

Bringing IPv6 to your local network The final step is to spread the love to your local network. Refrain from selecting addresses from your subnet and assigning them to the local hosts, or wondering how to configure the DHCP server, because IPv6 does it differently: your gateway will advertise its routes (which includes a default route) to your network, and each host will pick an address based on its MAC address (unless it already has an EUI-64 address assigned. This all happens automagically, at least with current Debian and Windows machines. On the gateway, you need to install radvd and simply tell it which prefix to use on which interface. My /etc/radvd looks like this, and I won t explain it:
interface eth0
  AdvSendAdvert on;
  prefix 2001:41e0:ff12::/64

Note again how we advertise a /64 network rather than the /48 we own . You cannot advertise smaller networks if you want automatic configuration to work, and you should not use networks larger than /64 in any case. If 2^64 addresses are not enough for you, I trust you ll be able to figure out how to advertise another of your 65536 /64 prefixes in the /48 subnet to appropriate hosts. Restart radvd and run over to another host to witness how it automagically gets connected to the IPv6 network by scanning /var/log/kern.log and watching the output of ip -6 addr and ip -6 route. Try ping6ing from there! Find the dancing turtle! It should all work. If you don t like the automagic aspect of this, look into stateful configuration, using DHCPv6, as provided by dibbler-server and ?wide-dhcpv6-server.

Resolving names Take note of the IPv6 address of each host. There s a way to determine it given the host s MAC address, but this is easier (ipv6calc is also useful). You might want to let your local DNS server know by adding AAAA records in parallel to the existing A records, and possibly even adding PTR entries. If you re serious about IPv6, you can tell SixXS to delegate reverse lookups for the IPv6 addresses to your DNS servers, but you ought to refrain from polluting the DNS namespace. Note that bind9-host provides an improved host tool, which fetches all kinds of information about names, not just the one single information configured as default:
% host has address has IPv6 address 2001:41e0:ff1a::1 mail is handled by 99 mail is handled by 10
% host 2001:41e0:ff1a::1
domain name pointer

Oh, and if you re really that curious about how IPv6 addresses are computed from MAC addresses, read RFC 2464. Basically, given a prefix 2001:41e0:ff1a:: and a MAC address aa:bb:cc:dd:ee:ff, the resulting IPv6 address is obtained by:
  1. inserting ff:fe into the middle of the MAC address to yield aa:bb:cc:ff:fe:dd:ee:ff;
  2. flipping the second lowest bit of the first octet to yield a8:bb:cc:ff:fe:dd:ee:ff;
  3. removing the odd colons to yield a8bb:ccff:fedd:eeff, the EUI-64;
  4. concatenating the prefix and this result to get 2001:41e0:ff1a::a8bb:ccff:fedd:eeff.
If you find your (Windows) IPv6 addresses changing all the time, you might be faced by privacy features .

Remaining issues Even though my IPv6 connectivity works, I have two remaining issues.

Sending larger amounts of data to the network I am experiencing a curious issue where outgoing ssh IPv6 connections time out and outgoing data transfers hiccup. I have yet to find out what s going on.

Mapping names to laptops Laptops generally have two interfaces, one with a cable, and the other wireless. Both of these interfaces will have separate MAC addresses, and by extension, the laptop will have different IPv6 addresses depending on how it is connected to the local network. I want to be able to connect to laptops without knowing the medium they use to connect to the network. Unfortunately, there seems to be no feasible way. The solutions I see are:
  • override the MAC address of one interface with that of the other, which is going to cause bgi problems in the case when the laptop (accidentally) gets connected to the same network twice;
  • add both IPv6 addresses as AAAA records to the laptop s DNS name, which will cause random delays when connecting as the resolver may return the currently inactive address first;
  • set up mobile IPv6, e.g. by following this Mobile IPv6 how-to, which would allow accessing the laptop uniformly, no matter where in the world it is. Unfortunately, Debian s support for Mobile IPv6 is severly lacking at time of writing. Also, Yves-Alexis Perez notes that this how-to is horribly outdated and promised to tend to it Real Soon Now .
The second solution works for me for now, but I am interested in the third. In response to this document, Andreas Henriksson has suggested the replace the stateless configuration (radvd) with stateful configuration, using DHCPv6. I have yet to investigate this option. Jeroen Massar suggests to unite cable and wireless into a bridged interface, which seems like a very good idea.

Credits Thanks to Bernhard Schmidt, William Boughton, and Jeroen Massar, and everyone on #ipv6/ for their help over the past few weeks, and all those who fed back comments in response to this document!

5 March 2007

Ross Burton: Tasks 0.3

Tasks 0.3 is out! The main new features are internationalisation and category filtering. A complete list of user-visible changes: I also had a few translations: Sources are available on the OpenedHand Projects site, and packages for Ubuntu Edgy, Ubuntu Feisty, and Debian Sid are in my repository. Adam Williamson has also packaged Tasks into Mandriva Contrib.

1 March 2007

Ross Burton: Tasks Translations (part 2)

I may give up actually coding in the future and just ask for things to be done on my blog.