Tag debian

Latest posts for tag debian

2017-01-11 12:43:32+01:00

Modern and secure instant messaging

Conversations is a really nice, actively developed, up to date XMPP client for Android that has the nice feature of telling you what XEPs are supported by the server one is using:

Initial server features

Some days ago, me and Valhalla played the game of trying to see what happens when one turns them all on: I would send her screenshots from my Conversations, and she would poke at her Prosody to try and turn things on:

After some work

Valhalla eventually managed to get all features activated, purely using packages from Jessie+Backports:

All features activated

The result was a chat system in which I could see the same conversation history on my phone and on my laptop (with gajim)(https://gajim.org/), and have it synced even after a device has been offline,

We could send each other rich media like photos, and could do OMEMO encryption (same as Signal) in group chats.

I now have an XMPP setup which has all the features of the recent fancy chat systems, and on top of that it runs, client and server, on Free Software, which can be audited, it is federated and I can self-host my own server in my own VPS if I want to, with packages supported in Debian.

Valhalla has documented the whole procedure.

If you make a client for a protocol with lots of extension, do like Conversations and implement a status page with the features you'd like to have on the server, and little green indicators showing which are available: it is quite a good motivator for getting them all supported.

debian eng pdo
2017-01-07 14:38:52+01:00

Teamwork

When I saw this video or this video I thought of this article.

When I feel part of a tightly coordinated and synchronized team I feel proud for the achievements of the team as a whole, which I see as bigger than what I could have achieved alone.

I also don't feel at risk of taking bad decisions. I feel less responsible. If I do what I'm told, I can't be blamed for doing the wrong things. I find it relaxing, every once in a while, to not have to be in charge.

I guess this could be part of the allure of a totalitarian regime: being freed from the burden of growing up

Thinking about this, reading those articles about romantic relationships, I see quite a bit of parallels also with organising cooperation and teamwork.

It looks like I ended up making parallels between Polyamory, Anarchism, and Free Software again. If you think there should traditionally be also a mention of BDSM, go back to "I find it relaxing, every once in a while, to not have to be in charge".

debian eng life pdo
2016-12-25 13:38:33+01:00

"Intervallo RAI" generator

During holiday idling, I made a thing to generate picture slideshows similar to RAI's iconic "Intervallo"

You can get it at https://github.com/spanezz/intervallo

Usage:

$ intervallo --help
usage: intervallo [-h] [--font file.ttf] [--audio file.mp3] [--duration sec]
                  imgfile [imgfile ...]

Create an Intervallo RAI out of a collection of images.

positional arguments:
  imgfile           input image files

optional arguments:
  -h, --help        show this help message and exit
  --font file.ttf   Font to use for subtitles
  --audio file.mp3  Audio track
  --duration sec    Time for each image in seconds

For example:

./intervallo --font DejaVuSerif.ttf --audio Paradisi-Toccata.mp3 *.jpg

The images are captioned with their file name, without extension. You may want to rename the image files to have nice descriptive names.

For some audio to use, you can try https://archive.org/details/IntervalloRai-Paradisi

Example

https://www.youtube.com/watch?v=ZCERwjTB4ck

debian eng pdo sw
2016-11-15 13:01:39+01:00

Software quality in 2016

Ansible's default output, including the stderr of failed commands, is JSON encoded, which makes reading Jenkins' output hard.

Ansible however has Callback plugins that could be used. In that page it says:

Ansible comes with a number of callback plugins that you can look at for examples. These can be found in lib/ansible/plugins/callback.

That is a link to a git repo with just a pile of Python sources and no, say README.md index to what they do. Hopefully they have some docstring with a short description of what they do? no.

Actually, some do, but just because someone copypasted the default one and didn't even bother removing its docstring.

frustration

debian eng pdo rant
2016-11-09 10:10:42+01:00

On SPF

I woke up this morning with some Django server error mails in my inbox:

UnicodeDecodeError: 'ascii' codec can't decode byte 0xc5 in position 9: ordinal not in range(128)
…
 'REMOTE_USER': u'…-guest@users.alioth.debian.org',

I did what one does in cases like these, I tried to fix the bug and mailed …-guest@users.alioth.debian.org asking them to try again and let me know if it works.

I get a bounce:

  <Actual user's email>
    (generated from …-guest@users.alioth.debian.org)
    SMTP error from remote mail server after MAIL FROM:<enrico@enricozini.org> SIZE=3948:
    host … […]: 550 Please see http://www.openspf.org/Why?id=enrico%40enricozini.org&ip=2001%3a41c8%3a1000%3a21%3a%3a21%3a21&receiver=bq :
    Reason: mechanism

I resent the mail to the actual user's address, and it went through. Job done, at least until they get back to me telling me that my fix didn't work.

Lessons learnt:

debian eng pdo sw
2016-11-02 16:54:06+01:00

schroot connector for ansible

I accidentally made an ansible connector plugin for schroot. I haven't even used ansible yet, so I have no idea what I am doing.

You can choose the chroot type by setting something like schroot_type: jessie in your variables.

You can install this locally as connection_plugins/schroot.py.

# Based on chroot.py (c) 2013, Maykel Moya <mmoya@speedyrails.com>
# Based on chroot.py (c) 2015, Toshio Kuratomi <tkuratomi@ansible.com>
# (c) 2016, Enrico Zini <enrico@debian.org>
#
# This is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Ansible is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Ansible.  If not, see <http://www.gnu.org/licenses/>.
from __future__ import (absolute_import, division, print_function)
__metaclass__ = type

import distutils.spawn
import os
import os.path
import pipes
import subprocess
import traceback

from ansible import constants as C
from ansible.errors import AnsibleError
from ansible.plugins.connection import ConnectionBase, BUFSIZE
from ansible.module_utils.basic import is_executable
from ansible.utils.unicode import to_bytes

try:
    from __main__ import display
except ImportError:
    from ansible.utils.display import Display
    display = Display()


class Connection(ConnectionBase):
    ''' Local chroot based connections '''

    transport = 'schroot'
    has_pipelining = True
    # su currently has an undiagnosed issue with calculating the file
    # checksums (so copy, for instance, doesn't work right)
    # Have to look into that before re-enabling this
    become_methods = frozenset(C.BECOME_METHODS).difference(('su',))

    def __init__(self, play_context, new_stdin, *args, **kwargs):
        super(Connection, self).__init__(play_context, new_stdin, *args, **kwargs)

        self.chroot = self._play_context.remote_addr

        #if os.geteuid() != 0:
            #raise AnsibleError("chroot connection requires running as root")

        # we're running as root on the local system so do some
        # trivial checks for ensuring 'host' is actually a chroot'able dir
        #if not os.path.isdir(self.chroot):
        #    raise AnsibleError("%s is not a directory" % self.chroot)

        #chrootsh = os.path.join(self.chroot, 'bin/sh')
        ## Want to check for a usable bourne shell inside the chroot.
        ## is_executable() == True is sufficient.  For symlinks it
        ## gets really complicated really fast.  So we punt on finding that
        ## out.  As long as it's a symlink we assume that it will work
        #if not (is_executable(chrootsh) or (os.path.lexists(chrootsh) and os.path.islink(chrootsh))):
        #    raise AnsibleError("%s does not look like a chrootable dir (/bin/sh missing)" % self.chroot)

        self.chroot_cmd = distutils.spawn.find_executable('schroot')
        if not self.chroot_cmd:
            raise AnsibleError("chroot command not found in PATH")

        self.chroot_id = "session:" + self.chroot
        self.chroot_type = "stable"
        existing = subprocess.check_output([self.chroot_cmd, "--list", "--all"])
        self.chroot_exists = False
        for line in existing.splitlines():
            if line == self.chroot_id:
                self.chroot_exists = True

    def set_host_overrides(self, host, hostvars=None):
        super(Connection, self).set_host_overrides(host, hostvars)
        self.chroot_type = hostvars.get("schroot_type", self.chroot_type)

    def _connect(self):
        ''' connect to the chroot; nothing to do here '''
        super(Connection, self)._connect()
        if not self._connected:
            if not self.chroot_exists:
                self.chroot_id = subprocess.check_output([self.chroot_cmd, "-b", "-c", self.chroot_type, "-n", self.chroot]).strip()
                subprocess.check_call([self.chroot_cmd, "-r", "-c", self.chroot_id, "-u", "root", "--", "apt-get", "update"])
                subprocess.check_call([self.chroot_cmd, "-r", "-c", self.chroot_id, "-u", "root", "--", "apt-get", "-y", "install", "python"])

            display.vvv("THIS IS A LOCAL CHROOT DIR", host=self.chroot)
            self._connected = True

    def _buffered_exec_command(self, cmd, stdin=subprocess.PIPE):
        ''' run a command on the chroot.  This is only needed for implementing
        put_file() get_file() so that we don't have to read the whole file
        into memory.

        compared to exec_command() it looses some niceties like being able to
        return the process's exit code immediately.
        '''
        executable = C.DEFAULT_EXECUTABLE.split()[0] if C.DEFAULT_EXECUTABLE else '/bin/sh'
        local_cmd = [self.chroot_cmd, "-r", "-c", self.chroot_id, "-u", "root", "--", executable, '-c', cmd]

        display.vvv("EXEC %s" % (local_cmd), host=self.chroot)
        local_cmd = [to_bytes(i, errors='strict') for i in local_cmd]
        p = subprocess.Popen(local_cmd, shell=False, stdin=stdin,
                stdout=subprocess.PIPE, stderr=subprocess.PIPE)

        return p

    def exec_command(self, cmd, in_data=None, sudoable=False):
        ''' run a command on the chroot '''
        super(Connection, self).exec_command(cmd, in_data=in_data, sudoable=sudoable)

        p = self._buffered_exec_command(cmd)

        stdout, stderr = p.communicate(in_data)
        return (p.returncode, stdout, stderr)

    def _prefix_login_path(self, remote_path):
        ''' Make sure that we put files into a standard path

            If a path is relative, then we need to choose where to put it.
            ssh chooses $HOME but we aren't guaranteed that a home dir will
            exist in any given chroot.  So for now we're choosing "/" instead.
            This also happens to be the former default.

            Can revisit using $HOME instead if it's a problem
        '''
        if not remote_path.startswith(os.path.sep):
            remote_path = os.path.join(os.path.sep, remote_path)
        return os.path.normpath(remote_path)

    def put_file(self, in_path, out_path):
        ''' transfer a file from local to chroot '''
        super(Connection, self).put_file(in_path, out_path)
        display.vvv("PUT %s TO %s" % (in_path, out_path), host=self.chroot)

        out_path = pipes.quote(self._prefix_login_path(out_path))
        try:
            with open(to_bytes(in_path, errors='strict'), 'rb') as in_file:
                try:
                    p = self._buffered_exec_command('dd of=%s bs=%s' % (out_path, BUFSIZE), stdin=in_file)
                except OSError:
                    raise AnsibleError("chroot connection requires dd command in the chroot")
                try:
                    stdout, stderr = p.communicate()
                except:
                    traceback.print_exc()
                    raise AnsibleError("failed to transfer file %s to %s" % (in_path, out_path))
                if p.returncode != 0:
                    raise AnsibleError("failed to transfer file %s to %s:\n%s\n%s" % (in_path, out_path, stdout, stderr))
        except IOError:
            raise AnsibleError("file or module does not exist at: %s" % in_path)

    def fetch_file(self, in_path, out_path):
        ''' fetch a file from chroot to local '''
        super(Connection, self).fetch_file(in_path, out_path)
        display.vvv("FETCH %s TO %s" % (in_path, out_path), host=self.chroot)

        in_path = pipes.quote(self._prefix_login_path(in_path))
        try:
            p = self._buffered_exec_command('dd if=%s bs=%s' % (in_path, BUFSIZE))
        except OSError:
            raise AnsibleError("chroot connection requires dd command in the chroot")

        with open(to_bytes(out_path, errors='strict'), 'wb+') as out_file:
            try:
                chunk = p.stdout.read(BUFSIZE)
                while chunk:
                    out_file.write(chunk)
                    chunk = p.stdout.read(BUFSIZE)
            except:
                traceback.print_exc()
                raise AnsibleError("failed to transfer file %s to %s" % (in_path, out_path))
            stdout, stderr = p.communicate()
            if p.returncode != 0:
                raise AnsibleError("failed to transfer file %s to %s:\n%s\n%s" % (in_path, out_path, stdout, stderr))

    def close(self):
        ''' terminate the connection; nothing to do here '''
        super(Connection, self).close()
        #subprocess.check_command([self.chroot_cmd, "-e", "-c", self.chroot_id])
        self._connected = False
debian eng pdo sw
2016-10-30 19:10:25+01:00

Bremen Freimarkt Parade

Look! They are having a parade with people dressed like Debian releases!

Bremen Freimarkt Parade

debian eng pdo
2016-10-18 10:25:55+02:00

debtags and aptitude forget-new

I like to regularly go through the new packages section in aptitude to see what interesting new packages entered testing, but recently that joyful moment got less joyful for me because of a barrage of obscurely named packages.

I have just realised that aptitude forget-new supports search patterns, and that brought back the joy.

I put this in a script that I run before looking for new packages in aptitude:

aptitude forget-new '?tag(field::biology)
                   | ?tag(devel::lang:ruby)
                   | ?tag(devel::lang:perl)
                   | ?tag(role::shared-lib)
                   | ?tag(suite::openstack)
                   | ?tag(implemented-in::php)
                   | ~n^node-'

The actual content of the search pattern is purely a matter of taste.

I'm happy to see how debtags becomes quite useful here, to keep my own user experience manageable as the size of Debian keeps growing.

Update: pabs suggested to use apt post-invoke hooks. For example:

        $ cat /etc/apt/apt.conf.d/99forget-new
        APT::Update::Post-Invoke { "aptitude forget-new '~sdebug'"; };
debian eng pdo
2016-06-15 21:47:28+02:00

Verifying gpg keys

Suppose you have a gpg keyid like 9F6C6333 that corresponds to both key 1AE0322EB8F74717BDEABF1D44BB1BA79F6C6333 and 88BB08F633073D7129383EE71EA37A0C9F6C6333, and you don't know which of the two to use.

You go to http://pgp.cs.uu.nl/ and find out that the site uses short key IDs, so the two keys are indistinguishable.

Building on Clint's hopenpgp-tools, I made a script that screenscrapes http://pgp.cs.uu.nl/ for trust paths, downloads all the potentially connecting keys in a temporary keyring, and runs hkt findpaths on it:

$ ./verify-trust-paths 1793D6AB75663E6BF104953A634F4BD1E7AD5568 1AE0322EB8F74717BDEABF1D44BB1BA79F6C6333
hkt (hopenpgp-tools) 0.18
Copyright (C) 2012-2016  Clint Adams
hkt comes with ABSOLUTELY NO WARRANTY. This is free software, and you are welcome to redistribute it under certain conditions.
(4,[1,4,3,6])

(1,1793D6AB75663E6BF104953A634F4BD1E7AD5568)
(3,F8921D3A7404C86E11352215C7197699B29B232A)
(4,C331BA3F75FB723B5873785B06EAA066E397832F)
(6,1AE0322EB8F74717BDEABF1D44BB1BA79F6C6333)

$ ./verify-trust-paths 1793D6AB75663E6BF104953A634F4BD1E7AD5568 88BB08F633073D7129383EE71EA37A0C9F6C6333
hkt (hopenpgp-tools) 0.18
Copyright (C) 2012-2016  Clint Adams
hkt comes with ABSOLUTELY NO WARRANTY. This is free software, and you are welcome to redistribute it under certain conditions.
(0,[])

This is a start: it could look in the local keyring for all ultimately trusted key finegrprints and use those as starting points. It could just take as an argument a short keyid and automatically check all matching fingerprints.

I'm currently quite busy with https://nm.debian.org and at the moment verify-trust-paths scratches enough of my itch that I can move on with my other things.

Please send patches, or take it over: I'd like to see this grow.

debian eng pdo sw
2016-06-15 10:14:43+02:00

On discomfort and new groups

I recenyly wrote:

When you get involved in a new community, such as Debian, find out early where, if that happens, you can find support, understanding, and help to make it stop.

Last night I asked a group of friends what do they do if they start feeling uncomfortable when they are alone in a group of people they don't know. Here are the replies:

I think a lot of these point are good food for thought about barriers of entry, and about safety nets that a group has or might want to have.

debian eng pdo