Search Results: "will"

22 March 2021

Wouter Verhelst: Twenty years of Debian

Ten years ago, I reflected on the fact that -- by that time -- I had been in Debian for just over ten years. This year, in early February, I've passed the twenty year milestone. As I'm turning 43 this year, I will have been in Debian for half my life in about three years. Scary thought, that. In the past ten years, not much has changed, and yet at the same time, much has. I became involved in the Debian video team; I stepped down from the m68k port; and my organizing of the Debian devroom at FOSDEM resulted in me eventually joining the FOSDEM orga team, where I eventually ended up also doing video. As part of my video work, I wrote SReview, for which in these COVID-19 times in much of my spare time I have had to write new code and/or fix bugs. I was a candidate for the position of DPL one more time, without being elected. I was also a candidate for the technical committee a few times, also without success. I also added a few packages to the list of packages that I maintain for Debian; most obviously this includes SReview, but there's also things like extrepo and policy-rcd-declarative, both fairly recent packages that I hope will improve Debian as a whole in the longer term. On a more personal level, at one debconf I met a wonderful girl that I now have just celebrated my first wedding anniversary with. Before that could happen, I have had to move to South Africa two years ago. Moving is an involved process at any one time; moving to a different continent altogether is even more so. As it would have been complicated and involved to remain a business owner of a Belgian business while living 9500km away from the country, I sold my shares to my (now ex) business partner; it turned the page of a 15-year chapter of my life, something I could not do without feelings one way or the other. The things I do in Debian has changed over the past twenty years. I've been the maintainer of the second-highest number of packages in the project when I maintained the Linux Gazette packages; I've been an m68k porter; I've been an AM, and briefly even an NM frontdesk member; I've been a DPL candidate three times, and a TC candidate twice. At the turn of my first decade of being a Debian Developer, I noted that people started to recognize my name, and that I started to be one of the Debian Developers who had been with the project longer than most. This has, obviously, not changed. New in the "I'm getting old" department is the fact that during the last Debconf, I noticed for the first time that there was a speaker who had been alive for less long than I had been a Debian Developer. I'm assuming these types of things will continue happening in the next decade, and that the future will bring more of these kinds of changes that will make me feel older as I and the project mature more. I'm looking forward to it. Here's to you, Debian; may you continue to influence my life, in good ways and in bad (but hopefully mostly good), as well as continue to inspire me to improve the world, as you have over the past twenty years!

19 March 2021

Antoine Beaupr : Securing my IRC (irssi, screen) session with dtach and systemd

A recent vulnerability in GNU screen caused some people to reconsider their commitment to the venerable terminal multiplexing program. GNU screen is probably used by thousands of old sysadmins around the world to run long-standing processes and, particularly, IRC sessions, which are especially vulnerable to arbitrary garbage coming on ... screen, so to speak. So this vulnerability matters, and you should definitely pay attention to it. If you haven't switched to tmux yet, now might be a good time to get your fingers trained. But don't switch to it just yet for your IRC session, and read on for a better, more secure solution. After all, it's not because we found this flaw in screen that it doesn't exist in tmux (or your favorite terminal emulator, for that matter, a much scarier thought).

Hardening my bouncer Back in March 2019, I had already switched away from screen for IRC, but not to tmux like many did, but to dtach. I figured that I didn't actually need multiplexing to run my long-running IRC session: I just needed to be able to reattach to the terminal. That's what dtach does. No windows, no panes, and, especially, no way to start a new shell, which is exactly the kind of hardening I need. So I came up with this, to start irssi:
dtach -N /run/$USER/dtach-irssi.socket irssi
To attach:
dtach -a /run/$USER/dtach-irssi.socket
Fairly simple no? Already one attack vector gone: evil attacker can't get a new shell through my terminal multiplexer, yay.

Splitting into another user But why stop there! Why am I running irssi as my main user anyways! Let's take the lessons from good UNIX security, and run this as a separate user altogether. This requires me to create another user, say foo-irc:
adduser foo-irc
... and run it as a systemd service, because how else are you going to start this thing anyways, cron? I came up with something like this unit file:
[Unit]
Description=IRC screen session
After=network.target
[Service]
Type=simple
Environment="TERM=screen.xterm-256color"
User=%i
RuntimeDirectory=%i
ExecStart=-/usr/bin/dtach -N /run/%i/dtach-irssi.socket irssi
ExecStop=-/bin/sh -c 'echo /quit stopping service...   exec /usr/bin/dtach -p /run/%i/dtach-irssi.socket'
ExecReload=-/bin/sh -c 'echo /restart   exec /usr/bin/dtach -p /run/%i/dtach-irssi.socket'
Notice this is a service template, because of the %i stuff. I don't actually remember how to enable this thing, but let's say you drop this in /etc/systemd/system/irssi@.service, then you run:
systemctl daemon-reload
And then, not sure about this bit, instantiate that template:
systemctl enable irssi@foo-irc.service
And then this should start the irssi session:
systemctl start irssi@foo-irc.service
To access the session:
sudo -u foo-irc dtach -a /run/foo-irc/dtach-irssi.socket
Obviously, you will probably need to migrate your irssi configuration over, otherwise you'll end up with a blank, old-school irssi. Take a moment to savor the view though. Nostalgia. Ah.

Hardening irssi But this is still not enough. That pesky foo-irc user can still launch arbitrary commands, thanks to irssi /exec (and a generous Perl scripting environment). Let's throw the entire kitchen sink at it and see what sticks. At this point, the unit file becomes too long to just maintain in a blog post (which would be silly, but not unheard of), so just look at this git repository instead.

Password-less remote irssi The neat thing with this hardening is that I now feel comfortable enough with the setup to just add a password-less SSH key to that (basically throwaway) account: worst that can happen if someone gets a hold of that SSH key is they land in a heavily sandboxed irssi session. So yay, no password to jump on chat. Like a real client or something. Just make sure to secure the SSH key you'll deploy in authorized_keys with:
restrict,pty,command="dtach -a /run/foo-irc/dtach-irssi.socket" [...]
Obviously, make sure the keys are not writable by the user, by placing it somewhere outside their home, which might require hacking at your server's SSH configuration. Because otherwise a compromised user will be able to change his own authorized_keys, which could be bad.

Configuration management And at this point, you may have noticed that you shouldn't actually followed my instructions to the letter. Instead, just use this neat little Puppet module which does all of the above, but also include some little wrapper so that mosh still works. It also includes instructions on how to setup your SSH keys. Enjoy, and let me know if (or rather, how) I messed up.

Updates
  1. it seems that dtach is not very active upstream: the last release (0.9) is from 2016, and the last commit (at the time of writing) is from 2017
  2. dtach is not necessarily safer than screen or tmux from arbitrary input from the outside, in fact there was a vulnerability on dtach CVE-2012-3368 that led to an attacker accessing stack memory (but maybe not code execution)
  3. after writing the Puppet module and publishing this article, I started to get weird behavior from dtach: i would leave the office at night and then return the next morning to find that I was timed out on servers. from my perspective, irssi noticed only when I re-attached the session:
    09:39:51 -!- Irssi: warning Broken pipe
    09:39:51 -!- Irssi: warning SSL write error: Broken pipe
    09:39:51 -!- Irssi: warning SSL write error: Broken pipe
    09:39:51 -!- Irssi: warning SSL write error: Broken pipe
    09:39:51 -!- Irssi: warning SSL write error: Broken pipe
    09:39:51 [bitlbee] -!- Irssi: Connection lost to localhost
    09:39:51 -!- Irssi: warning SSL write error: Broken pipe
    09:39:51 [gitter] -!- Irssi: Connection lost to irc.gitter.im
    09:39:51 [OFTC] -!- Irssi: Connection lost to irc.oftc.net
    09:42:34 [IMC] -!- Irssi: Connection lost to irc.indymedia.org
    09:42:34 -!- Irssi: Connection lost to irc.hackint.org
    09:42:34 -!- Irssi: Connection lost to chat.freenode.net
    09:42:34 -!- dtach_away: Set away
    
    from the outside I actually timed out a few minutes after I detached, which also makes for a weird asymmetry:
    22:31:00 -!- anarcat [~anarcat@ocean] has quit [Ping timeout: 250 seconds]
    
    that is eleven hours before the error I get.
  4. the mosh wrapper script seems to not work as well as it did before. somehow just running mosh $server hangs with a blank screen instead of instantly rejoining the session. I'm not sure it is related to the timeout problem but I did rewrite the wrapper before publication. this is the old version:
    #!/bin/sh
    # inspired by https://serverfault.com/questions/749474/ssh-authorized-keys-command-option-multiple-commands
    command="dtach -a /run/anarcat-irc/dtach-irssi.socket"
    case "$SSH_ORIGINAL_COMMAND" in
        mosh-server*)
        exec mosh-server -- $command
        ;;
        *)
        exec $command
        ;;
    esac
    
    I'm thinking of trying that one out for a while to see if it's related. The weirdest thing is that mosh "un-hangs" if i reattach with plain ssh, so there's definitely something fishy going on here.

18 March 2021

Arturo Borrero Gonz lez: Debugging ip token set RTNETLINK error

Networking At the Wikimedia Foundation they configure basically all servers with IPv4/IPv6 dual stack, at least in the control plane interface (those used for SSH management, etc). IPv6 is not supported yet on the Cloud Services dataplane (openstack), but it will in the near future. An elegant solution for this IPv4/IPv6 dual stack configuration in the control plane is to embed the IPv4 address into the IPv6 address, something like this:
IPv4: 208.80.154.23
IPv6: 2620:0:861:1:208:80:154:23
                   ^^^^^^^^^^^^^
The gateways send prefix advertisements and by default IPv6 autoconfiguration uses such routers prefixes plus the interface MAC address to build the final address. This behavior can be somewhat changed, you can explicitly set some data instead of the MAC address for the kernel to use when building the final IPv6 address. The trick is to use the ip token command, and further context and reasoning for this can be seen in the puppet manifest that the SRE team uses to configure this:
The token command explicitly configures the lower 64 bits that will be used with any autoconf
address, as opposed to one derived from the macaddr. This aligns the autoconf-assigned address with
the fixed one set above, and can do so as a pre-up command to avoid ever having another address
even temporarily, when this is all set up before boot.
For example:
user@debian:~$ sudo ip token list
token ::208:80:154:23 dev eno1
token :: dev eno2
token :: dev eno3
token :: dev eno4
user@debian:~$ sudo ip token set dev eno2 ::beef
user@debian:~$ ip token get dev eno2
token ::beef dev eno2
user@debian:~$ ip token list
token ::208:80:154:23 dev eno1
token ::beef dev eno2
token :: dev eno3
token :: dev eno4
I was installing a new server the other day and the networking service (ifupdown) was failing to bring the interface up. The issue was the ip token command failing:
root@cloudgw2002-dev:~# ip token set ::10:192:20:18 dev eno1
RTNETLINK answers: Invalid argument
RTNETLINK error reporting is awful. What could be wrong about that command? Well, I had to dig into the kernel source code to try figuring out where was that EINVAL being generated. The routine can be seen in the function inet6_set_iftoken() (source):
static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
 
	struct inet6_ifaddr *ifp;
	struct net_device *dev = idev->dev;
	bool clear_token, update_rs = false;
	struct in6_addr ll_addr;
	ASSERT_RTNL();
	if (!token)
		return -EINVAL;
	if (dev->flags & (IFF_LOOPBACK   IFF_NOARP))
		return -EINVAL;
	if (!ipv6_accept_ra(idev))
		return -EINVAL;
	if (idev->cnf.rtr_solicits == 0)
		return -EINVAL;
[..]
I couldn t identify the reason at first glance, apparently I pass every check in there: Something was wrong here. Upon deeper checks, I finally read the ipv6_accept_ra() function (source):
static inline bool ipv6_accept_ra(struct inet6_dev *idev)
 
	/* If forwarding is enabled, RA are not accepted unless the special
	 * hybrid mode (accept_ra=2) is enabled.
	 */
	return idev->cnf.forwarding ? idev->cnf.accept_ra == 2 :
	    idev->cnf.accept_ra;
 
That was it! Forwarding was enabled on the interface, and it shouldn t. I fixed my configuration with a simple patch for the sysctl configuration. Original issue on the Wikimedia Foundation ticketing system: Phabricator T277287

14 March 2021

Russ Allbery: New experimental Big Eight Usenet signing key

I have finally done the work to create a new modern GnuPG signing key for control messages for the Big Eight hierarchies and wired it into the machinery that sends those control messages. I have sent one experimental checkgroups message signed with that key:
    <cmsg-20210314174844$1888@isc.org>
To test the automation, tomorrow the normal monthly checkgroups will be issued, which should result in two control messages, one signed with the new key and one with the old key. I've used the same key ID for the new key as the old key so that updating will be as simple as importing the new key. This key is currently EXPERIMENTAL and I reserve the right to reissue the key if anyone uncovers any problems. If you are in a position to do so, please try verifying the control messages with the new key and verify that the work properly. I plan on making this new key official some time next month and will post a more general announcement to news.announce.newgroups and news.admin.announce at that time. The new key, signed with my personal key and the old hierarchy control signing key, is available on my web site. (The Big Eight hierarchies need a more official information page for news administrators, I know, but one thing at a time.)

13 March 2021

Enrico Zini: nspawn-runner and ansible

This post is part of a series about trying to setup a gitlab runner based on systemd-nspawn. I published the polished result as nspawn-runner on GitHub. New goal: make it easier to configure and maintain chroots. For example, it should be possible to maintain a rolling testing or sid chroot without the need to manually log into it to run apt upgrade. It should be also be easy to have multiple runners reasonably in sync by carrying around a few simple configuration files, representing the set of images available to the CI. Ideally, those configuration files could simply be one ansible playbook per chroot. nspawn-runner could have a 'chroot-maintenance' command that runs all the playbooks on their corresponding chroots, and that would be all I need. ansible and systemd-nspawn ansible being inadequate as usual, it still does not have a nspawn or machinectl connector, even though the need is there, and one can find requests, pull requests, and implementation attempts by all sorts of people, including me. However, I don't want to have nspawn-runner depend on random extra plugins. There's a machinectl become plugin available in ansible from buster-backports, but no matter how I read its scant documentation, looked around the internet, and tried all sorts of things, I couldn't manage to figure out what it is for. This said, simply using systemd-nspawn instead of chroot is quite trivial: use ansible_connection: chroot, set ansible_chroot_exe to this shellscript, and it just works, with things properly mounted, internet access, correct hostnames, and everything:
#!/bin/sh
chroot="$1"
shift
exec systemd-nspawn --console=pipe -qD "$chroot" -- "$@"
I guess that's a, uhm, plan, I guess? Running playbooks As an initial prototype, I made nspawn check the list of chroots in /var/lib/nspawn-runner, and for each directory found there, check if there's an equivalent .yaml or .yml file next to nspawn-runner. For each chroot+playbook combination, it creates an inventory with the right setup, including the custom chroot command, and runs ansible-playbook. As a prototype it works. I assume once it will see usage there's going to be feedback and fine tuning; meanwhile, I have the beginning of some automated maintenance for the CI chroots. Next step It would be nice to also have nspawn-runner create the chroots from configuration files if they are missing, so that a new runner can be deployed with a minimal effort, and it will proceed to generate all the images required in a single command. For this, I'd like to find a clean way to store the chroot creation command inside the playbooks, to keep just one configuration file per chroot. I'd also like to have it flexible enough to run debootstrap, as well as commands for different distributions. Time will tell. This is probably enough for study/design posts on my blog. Further updates will be in the issue tracker.

Louis-Philippe V ronneau: Preventing an OpenPGP Smartcard from caching the PIN eternally

While I'm overall very happy about my migration to an OpenPGP hardware token, the process wasn't entirely seamless and I had to hack around some issues, for example the PIN caching behavior in GnuPG. As described in this bug the cache-ttl parameter in GnuPG is not implemented and thus does nothing. This means once you type in your PIN, it is cached for as long as the token is plugged. Security-wise, this is not great. Instead of manually disconnecting the token frequently, I've come up with a script that restarts scdameon if the token hasn't been used during the last X minutes. It seems to work well and I call it using this cron entry: */5 * * * * my_user /usr/local/bin/restart-scdaemon To get a log from scdaemon, you'll need a ~/.gnupg/scdaemon.conf file that looks like this:
debug-level basic
log-file /var/log/scdaemon.log
Hopefully it can be useful to others!
 #!/usr/bin/python3
# Copyright 2021, Louis-Philippe V ronneau <pollo@debian.org>
#
# This script 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.
# 
# This script 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
# this script. If not, see <http://www.gnu.org/licenses/>.
"""
This script restarts scdaemon after X minutes of inactivity to reset the PIN
cache. It is meant to be ran by cron each X/2 minutes.
This is needed because there is currently no way to set a cache time for
smartcards. See https://dev.gnupg.org/T3362#137811 for more details.
"""
import os
import sys
import subprocess
from datetime import datetime, timedelta
from argparse import ArgumentParser
p = ArgumentParser(description=__doc__)
p.add_argument('-l', '--log', default="/var/log/scdaemon.log",
               help='Path to the scdaemon log file.')
p.add_argument('-t', '--timeout', type=int, default="10",
               help=("Desired cache time in minutes."))
args = p.parse_args()
def get_last_line(scdaemon_log):
    """Returns the last line of the scdameon log file."""
    with open(scdaemon_log, 'rb') as f:
        f.seek(-2, os.SEEK_END)
        while f.read(1) != b'\n':
            f.seek(-2, os.SEEK_CUR)
        last_line = f.readline().decode()
    return last_line
def check_time(last_line, timeout):
    """Returns True if scdaemon hasn't been called since the defined timeout."""
    # We don't need to restart scdaemon if no gpg command has been run since
    # the last time it was restarted.
    should_restart = True
    if "OK closing connection" in last_line:
        should_restart = False
    else:
        last_time = datetime.strptime(last_line[:19], '%Y-%m-%d %H:%M:%S')
        now = datetime.now()
        delta = now - last_time
        if delta <= timedelta(minutes = timeout):
            should_restart = False
    return should_restart
def restart_scdaemon(scdaemon_log):
    """Restart scdaemon and verify the restart process was successful."""
    subprocess.run(['gpgconf', '--reload', 'scdaemon'], check=True)
    last_line = get_last_line(scdaemon_log)
    if "OK closing connection" not in last_line:
        sys.exit("Restarting scdameon has failed.")
def main():
    """Main function."""
    last_line = get_last_line(args.log)
    should_restart = check_time(last_line, args.timeout)
    if should_restart:
        restart_scdaemon(args.log)
if __name__ == "__main__":
    main()

12 March 2021

Ryan Kavanagh: Static Comments in Hugo

I switched from Jekyll to Hugo last week for a variety of reasons. One thing that was missing was a port of the jekyll-static-comments plugin that I used to use. I liked it because it saved readers from being tracked by Disqus or other comments solutions, and it required no javascript. To comment, users would email me their comment following a template attached to the bottom of each post. I then piped their email through a script to add it to the right post. As an added benefit, I could delegate comment spam detection to my mail server. I ve managed to reimplement this setup using Hugo. For those who are interested in a similar setup, here is what you need to do.

Pages with comments Instead of being single files, pages need to be leaf bundles. For example, this means that your blog post must be located at /content/blog/2021-03-12-static-comments-in-hugo/index.md instead of /content/blog/2021-03-12-static-comments-in-hugo.md. This lets you store the comments as page resources in the subdirectory /content/blog/2021-03-12-static-comments-in-hugo/comments/.

Partials You should create a comments.html partial and include it in the layout for the pages which should get comments:
<div class="post-comments">
  <p class="comment-notice"><b>Comments</b>: To comment on this post,
	send me an email following the template below. Your email address
	will not be posted, unless you choose to include it in
	the <span style="font-family: monospace;">link:</span> field.</p>
  <pre class="comment-notice">
To: Your Name &lt;your.email<span>@</span>example.org&gt;
Subject: [blog-comment]   .Page.RelPermalink  
post_id:   .Page.RelPermalink  
author: [How should you be identified? Usually your name or "Anonymous"]
link: [optional link to your website]
Your comments here. Markdown syntax accepted.</pre>
    $scratch := newScratch  
    $scratch.Set "comments" (.Resources.Match "comments/*yml")  
    if eq 1 (len ($scratch.Get "comments"))  
  <h2>1 Comment</h2>
    else  
  <h2>  len ($scratch.Get "comments")   Comments</h2>
    end  
    range ($scratch.Get "comments")  
  <div class="post-comment  % cycle 'odd', 'even' % ">
	  $comment := (.Content   transform.Unmarshal)  
	<span class="post-meta">
		 - $comment.date   dateFormat "Jan 2, 2006 at 15:04" - 
	</span>
	<h3 class="comment-header">
	    if $comment.link  
	  <a href="  $comment.link  ">  $comment.author  </a>
	    else  
	    $comment.author  
	    end  
	  <br />
	</h3>
	  $comment.comment   markdownify  
  </div>
    end  
</div>

Comments To associate comments received by email to posts, I pipe them from mutt (using the keybinding) to the following (admittedly janky) shell script. It takes the comment, reformats it appropriately, and puts it in the post s comments subdirectory. Note that it determines which filename to use based on the email s contents, so make sure to check that the email doesn t contain anything nefarious before you pipe it into the script!
#!/bin/sh
# Copyright (C) 2016-2021 Ryan Kavanagh <rak@rak.ac>
# Distributed under the ISC license
BLOG_BASE="/media/t/work/blog"
MESSAGE=$(cat)
EMAIL=$(echo "$ MESSAGE "   grep "From:"   sed -e 's/From[^<]*<\?\([^>]*\)>\?.*/\1/g;s/@/-at-/g')
DATE=$(echo "$ MESSAGE "   grep "Date:"   sed -e 's/Date:\s*//g'   xargs -0 date -Iseconds -u -d)
POST_ID=$(echo "$ MESSAGE "   grep "post_id:"   sed -e 's/post_id: //g')
COMMENTS_DIR="$ BLOG_BASE /content/$ POST_ID /comments/"
COMMENT_FILE="$ COMMENTS_DIR /$ DATE _$ EMAIL .yml"
# Strip out the email headers and whitespace until the start of the comment
COMMENT_WHOLE=$(echo "$ MESSAGE "   sed -e '/^\s*$/,$!d;/^[^\s]/,$!d')
# Indent everything after the comment header
COMMENT_INDENTED=$(echo "$ COMMENT_WHOLE "   sed -e '/^\s*$/,$ s/.*/  &/g ')
# And add the comment header
COMMENT_PREFIXED=$(echo "$ COMMENT_INDENTED "   sed -e '0,/^\s*$/ s/^\s*$/comment:  / ')
[ -d "$ COMMENTS_DIR " ]   mkdir -p "$ COMMENTS_DIR "
echo "Saving the comment to $ COMMENT_FILE "
echo "date: $ DATE "   tee "$ COMMENT_FILE "
echo "$ COMMENT_PREFIXED "   tee -a "$ COMMENT_FILE "
For example, the following comment in an email body:
post_id: /blog/2021-03-12-static-comments-in-hugo/
author: Ryan Kavanagh
link: https://rak.ac/
Dear self,
Here is a test comment for your blog post.
It supports *markdown* **syntax** and  stuff .
Best,
Yourself
results in a file content/blog/2021-03-12-static-comments-in-hugo/comments/2021-03-12T18:47:25+00:00_rak-at-example.org.yml containing:
date: 2021-03-12T18:47:25+00:00
post_id: /blog/2021-03-12-static-comments-in-hugo/
author: Ryan Kavanagh
link: https://rak.ac/
comment:  
  Dear self,

  Here is a test comment for your blog post.
  It supports *markdown* **syntax** and  stuff .

  Best,
  Yourself  
You can see the rendered output at the bottom of this page.

10 March 2021

Sean Whitton: consfigurator 0.3.1

I d like to briefly introduce my new project, Consfigurator:
Consfigurator is a system for declarative configuration management using Common Lisp. You can use it to configure hosts as root, deploy services as unprivileged users, build and deploy containers, and produce disc images. [not all of these are implemented yet, but the design permits them to be] Consfigurator s design gives you a great deal of flexibility about how to control the hosts you want to configure. If there is a command you can run which will obtain input and output streams attached to an interactive POSIX sh running on the target host/container, then with a little glue code, you can use much of Consfigurator s functionality to configure that host/container. But if it is possible to get an implementation of Common Lisp started up on the host, then Configurator can transparently execute your deployment code over on the remote side, rather than exchanging information via POSIX sh. This lets you use the full power of Common Lisp to deploy your configuration. Configurator has convenient abstractions for combining these different ways to execute your configuration on hosts with different ways of connecting to them. Connections can be arbitrarily nested. For example, to combine SSHing to a Debian machine as an unprivileged user, using sudo to become root, and then starting up a Lisp image to execute your deployment code, you would evaluate
    (deploy ((:ssh (:sudo :as "spwhitton@athena.example.com") :debian-sbcl)) athena.example.com)
Declarative configuration management systems like Consfigurator and Propellor share a number of goals with projects like the GNU Guix System and NixOS. However, tools like Consfigurator and Propellor try to layer the power of declarative and reproducible configuration on top of traditional, battle-tested unix system administration infrastructure like apt, dpkg, yum, and distro package archives, rather than seeking to replace any of those. Let s get as much as we can out of all that existing distro policy-compliant work!
Please check out the user s manual, which includes a tutorial/quick start guide, and come join us in #consfigurator on irc.oftc.net. It s early days but you can already do a fair few things with Consfigurator. It s a good time to come help get all the basic properties defined!

Dirk Eddelbuettel: RcppArmadillo 0.10.2.2.0 on CRAN: New Upstream Patch Release

armadillo image Armadillo is a powerful and expressive C++ template library for linear algebra aiming towards a good balance between speed and ease of use with a syntax deliberately close to a Matlab. RcppArmadillo integrates this library with the R environment and language and is widely used by (currently) 841 other packages on CRAN. This release brings us a second update within the Armadillo 10.2 series, one month after the initial release. Upstream work has commenced at a 10.3 series with first pre-releases which we are currently testing. If possible, CRAN release will continue to be at least one month apart (such as this time) but we continue to make interim releases available on the Rcpp drat repo repo. The full set of changes follows.

Changes in RcppArmadillo version 0.10.2.2.0 (2021-03-09)
  • Upgraded to Armadillo release 10.2.2 (Cicada Swarm)
    • faster handling of subcubes
    • added tgamma()
    • added .brief_print() for abridged printing of matrices & cubes
    • expanded forms of trimatu() and trimatl() with diagonal specification to handle sparse matrices
    • expanded eigs_sym() and eigs_gen() with optional shift-invert mode
  • Removed debian/ directory from repository as packaging is on salsa.debian.org.
  • Relaxed tolerance on two cube tests on Windows to accomodate new 'gcc10-UCRT' builder.

Courtesy of my CRANberries, there is a diffstat report relative to previous release. More detailed information is on the RcppArmadillo page. Questions, comments etc should go to the rcpp-devel mailing list off the R-Forge page. If you like this or other open-source work I do, you can sponsor me at GitHub.

This post by Dirk Eddelbuettel originated on his Thinking inside the box blog. Please report excessive re-aggregation in third-party for-profit settings.

9 March 2021

Matthew Garrett: Unauthenticated MQTT endpoints on Linksys Velop routers enable local DoS

(Edit: this is CVE-2021-1000002)

Linksys produces a series of wifi mesh routers under the Velop line. These routers use MQTT to send messages to each other for coordination purposes. In the version I tested against, there was zero authentication on this - anyone on the local network is able to connect to the MQTT interface on a router and send commands. As an example:
mosquitto_pub -h 192.168.1.1 -t "network/master/cmd/nodes_temporary_blacklist" -m ' "data": "client": "f8:16:54:43:e2:0c", "duration": "3600", "action": "start" '
will ask the router to block the client with MAC address f8:16:54:43:e2:0c from the network for an hour. Various other MQTT topics pass parameters to shell scripts without quoting them or escaping metacharacters, so more serious outcomes may be possible.

The vendor has released two firmware updates since report - I have not verified whether either fixes this, but the changelog does not indicate any security issues were addressed.

Timeline:

2020-07-30: Submitted through the vendor's security vulnerability report form, indicating that I plan to disclose in either 90 days or after a fix is released. The form turns out to file a Bugcrowd submission.
2020-07-30: I claim the Bugcrowd submission.
2020-08-19: Vendor acknowledges the issue, is able to reproduce and assigns it a P3 priority.
2020-12-15: I ask if there's an update.
2021-02-02: I ask if there's an update.
2021-02-03: Bugcrowd raise a blocker on the issue, asking the vendor to respond.
2021-02-17: I ask for permission to disclose.
2021-03-09: In the absence of any response from the vendor since 2020-08-19, I violate Bugcrowd disclosure policies and unilaterally disclose.

comment count unavailable comments

Sylvestre Ledru: Debian running on Rust coreutils

tldr: Rust/coreutils ( https://github.com/uutils/coreutils/ ) is now available in Debian, good enough to boot a Debian with GNOME, install the top 1000 packages, build Firefox, the Linux Kernel and LLVM/Clang. Even if I wrote more than 100 patches to achieve that, it will probably be a bumpy ride for many other use cases.
It is also a terrific project to learn Rust. See the list of good first bugs. Even if I see Rust code every day at Mozilla, I was looking for an actual personal project (i.e. this isn't a Mozilla project) to learn Rust during the various COVID lockdowns. I started contributing to the alternative Coreutils developed in Rust. The project aims at proposing a drop-in replacement of the C-based GNU Coreutils, and I wanted to evaluate if this could be used to run a regular Debian. Similar to what I have done with clang.debian.net a few years ago (rebuilding the Debian archive using clang instead of gcc). I expect that most of the readers know what is the Coreutils. It is a set of programs performing simple operations (copy/move file, change permissions/ownership, etc). Even if some commands are from the 70s, they are at the base of Linux, Unix and macOS. While different implementations can be found, they are trying to remain compatible in terms of arguments, options, etc. This implementation of Coreutils isn t different! If you want to learn more about the history of Unix, I recommend this great Corecursive podcast with Brian Kernighan. While a lot of people contributed to this project, much was left to be done: To start easy, I defined 4 goals for this work:
  1. Package Coreutils in Debian/Ubuntu
  2. Boot a Debian system with a Rust-based coreutils
  3. Install the top 1000 packages in Debian - including GNOME
  4. Build Firefox, the Linux Kernel and LLV/Clang

Packaging of Coreutils in Debian Packaging in Debian isn't a trivial or even simple task. It requires uploading independently all the dependencies in the archive. Rust, with its new ecosystem and small crates, is making this task significantly harder. The package is called rust-coreutils - https://tracker.debian.org/pkg/rust-coreutils For Debian/Ubuntu users, to have an idea of the complexity of packaging such applications, just run
debtree --build-dep rust-coreutils dot -Tsvg > coreutils.svg (should be around 1M). Since it isn't production ready, the rust-coreutils is installable in parallel with coreutils. This package does NOT replace the GNU/coreutils files (yet?), the new files are installed in /usr/lib/cargo/bin/. They can be used with: export PATH=/usr/lib/cargo/bin/:$PATH Or, uglier, overriding the files with the new ones.

Booting Debian with rust-coreutils To achieve this, because I knew I would likely break the image a few times, I created a new project to quickly install a full Debian with PXE and preseed. The project is available here: https://github.com/opencollab/qemu-debian-install-pxe-preseed/ A script to create the full qemu image: build_qemu_debian_image.sh A second script to boot on the newly created image: boot.sh Then, building and installing coreutils on the system (yeah, it is ugly - don t do that at home): apt install rust-coreutils
cd /usr/lib/cargo/bin/
for f in *; do
cp -f $f /usr/bin/
done
First surprise, unlike the old init.d init system, as systemd is not relying on a series of scripts (it is mostly written in C), replacing the coreutils did not have an impact. Therefore, I didn't experience any issue during the boot process

Implementing missing options A significant number of problems could be easily identified as a lack of support for some options. Here is a list of most of the fixes I had to implement to make this plan work:

Different behavior Most of the programs behaved as expected. Here is a list of differences:
  • install doesn't support using /dev/null as source file
    Setting up libreoffice-common (1:6.1.5-3+deb10u6) ...
    install: error: install: cannot install /dev/null to /etc/apparmor.d/local/usr.lib.libreoffice.program.oosplash : the source path is not an existing regular file
    A limitation of rust itself https://github.com/rust-lang/rust/issues/79390

Compile Firefox, Clang and the Linux Kernel Build systems can vary significantly one from the other. To verify their usage of coreutils, I built these three major projects

Firefox As Firefox relies mostly on Python as a build system, it went smoothly. I didn t encounter any issue. The only unrelated issue that I noticed working on it was apt-key was broken because the script relied on a buggy option of mktemp.

Linux Kernel I identified only two issues compared to GNU Coreutils:
  • The chown command on a non-existing symlink target doesn t fail on the GNU version, the Rust one was triggering an error.
    https://github.com/uutils/coreutils/pull/1694
  • Linux kernel
    ln -fsn ../../x86/boot/bzImage ./arch/x86_64/boot/bzImage
    ln: error: Unrecognized option: 'n'

LLVM/Clang The llvm toolchain relies on Cmake. Just like for Firefox, I didn t face any issue.

Comparing with GNU coreutils using its testsuite Recently, James Robson added a new test to run the GNU testsuite on the Rust/coreutils.

# TOTAL: 611
# PASS: 144
# SKIP: 86
# XFAIL: 0
# FAIL: 342
# XPASS: 0
# ERROR: 39
compared to 546 test passing with the GNU version. Even if a bunch of errors are just different outputs, it demonstrates that there is still a long road ahead.

Next steps & contribute First, we will need more motivated contributors to work on this project. Many features remain to be implemented, optimizations to be done (e.g. decreasing the memory usage), etc.
I started to create a list of good first bugs for newcomers: https://github.com/uutils/coreutils/issues?q=is%3Aissue+is%3Aopen+label%3A%22Good+first+bug%22
I will update this list of there is some interest for this project.
Helping improve the support of the GNU coreutils testsuite would be a huge step while being a great way to learn Rust! Then, once it is in a better state, we will be able to make it a reliable alternative in Debian/Ubuntu to the GNU/Coreutils. This might be also interesting for other folks who prefer a BSD license over a GPL.

7 March 2021

Louis-Philippe V ronneau: New Year, New OpenPGP Key

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA512
Sun, 07 Mar 2021 13:00:17 -0500
I've recently set up a new OpenPGP key and will be transitioning away from my
old one.
It is a chance for me to start using a OpenPGP hardware token and to transition
to a new personal email address (my main public contact is still my
 @debian.org  address).
Please note that I've partially redacted some email addresses from this
statement to minimise the amount of spam I receive. It shouldn't be hard for
actual humans to follow the instructions below to find the complete addresses.
The old key will continue to be valid for a few months, but will eventually be
revoked.
You might know my old OpenPGP certificate as:
pub   rsa4096/0x7AEAC4EC6AAA0A97 2014-12-22 [expires: 2021-06-02]
      Key fingerprint = 677F 54F1 FA86 81AD 8EC0  BCE6 7AEA C4EC 6AAA 0A97
uid       Louis-Philippe V ronneau <REDACTED@riseup.net>
uid       Louis-Philippe V ronneau (alias) <REDACTED@riseup.net>
uid       Louis-Philippe V ronneau (debian) <REDACTED@debian.org>
My new OpenPGP certificate is:
pub   ed25519/0xE1E5457C8BAD4113 2021-03-06 [expires: 2022-03-06]
      Key fingerprint = F64D 61D3 21F3 CB48 9156  753D E1E5 457C 8BAD 4113
uid       Louis-Philippe V ronneau <REDACTED@veronneau.org>
uid       Louis-Philippe V ronneau <REDACTED@debian.org>
These days, I mostly use my key for Debian and to sign git commit. I don't
really expect you to sign my new key if you had signed my old one.
I've published the new certificate on keys.openpgp.org as well as on my
personal website. You can fetch it like this:
    $ wget -O- https://veronneau.org/media/openpgp.key   gpg --import
-----BEGIN PGP SIGNATURE-----
iQIzBAEBCgAdFiEEZ39U8fqGga2OwLzmeurE7GqqCpcFAmBFFM8ACgkQeurE7Gqq
CpcuchAAscAeszdtA+TlCI4YvK5nlk+nJnCnNBSnl7Et+jiNjq8kB/Fud+dWMTXC
Zag8oJkalbbxub0BT0bEAn+BiBunu58E0gd0Xq4syTbqZ5o5IN17S/tfxCD0k1hf
ewrnYZ2l0i5g4YvHGKC+Xv4D+Z84BylnIRaXHqlUdluOVfVYDfLybOAqoktO/KUH
I+vQBwXj0Fr/QAtgiz5Nwh/YHFiU9xMSvr5ozRwAFs6+xfIqFHuVPRRkEN5iVo4D
kkMIz+kFfkoh4aWIP4dgAu39XnEgxwTR9J+4yE8TzCCMzO7xCK0X6vqgPAxYMPvb
RuP4FnGWOnGnlcudCUAUkOaryrwRi+dPQTnNICHTYsvVc7dg+W0EhVUkwEuuEwpI
qtcB/Y5AGhqK0Cc11uXiFjIQwLTgwcUez4F0xrGeqsTtAM5gyRup2w0jbocTuYSh
ZRv/2zwrq/S3xVrUYGqdT+L5odmkBzz9zOwY5WlU2H9CMFOdh71XOv9wWQXan9ou
hLRodeOQ8MinIBP+sX36ol1zg/aP7mCHvRRSBzWt7l3WhVxgZFpNwIfp/RZqU0R4
IEq48mntFhPvHJjFmAKLKK/ckzNMtSn+HWQPJV3HTInKCTu5PTNMU3SAvPHOHEps
V6WWSOPB+1Lm/tlIULDc+0SopWoiWO4NObCSs8zMZHlYPBk5x/KIdQQBFgoAHRYh
BMqnQAcHqBawIC/DzfQlelCyHPqFBQJgRRTPAAoJEPQlelCyHPqFFVEA/1qScaAk
O+eBEE4q0BaJDsqweCS1XCcuQGkQCKi5Zv6kAQChQ96Ve7cKbN/wRkT9pdIhmx01
+CmIsnp3k6N0ZYLLCg==
=onl0
-----END PGP SIGNATURE-----

6 March 2021

Shirish Agarwal: Making life difficult

Freedom house puts India in partly free Just couple of days ago, freedom house published its 2020 rankings for all countries including India. While freedom house shared how democracy in the world has weakened, India chose to take offense about it being called partly free .
India, leader in Internet shutdowns Access Now (copyright)
The above illustration is shared by accessnow . The next big ones who have Internet shutdowns are Yemen 6 and Ethiopia 4. Such internet shutdowns have and will have sad repercussions as would share in another story as well.

Color-coding journalists A story was broken by caravan magazine yesterday and which was followed by newslaundry which shows how the Govt. is looking to just drive some narrative, does not matter whether it s true or false, it should just show that the Govt. is right and others are all wrong. As can be seen, almost all reporters barring a few have kept silent rather than refuting statements attributed to them or happenings which didn t happen. And this goes to a much larger narrative and disinformation route taken by the Govt. which doesn t have any semblance to the truth or reality as people know it. I would illustrate couple of examples below which shares that. In all my young and even adult-life I hadn t seen a Govt. this much against its own people.

Omega Seiki puts a manufacturing plant in Bangladesh Now Omega Seiki is an Indian vendor who chose or had to go to manufacture their electric vehicles in Bangladesh. Now while this is a slightly old story this was broken on social media recently. Everybody starting blaming both the vendor and saying we should break FTA (Free Trade Agreement) with Bangladesh, not knowing that despite the FTA, India has put tariff barriers between India and Bangladesh. I had to share research from Brookings to show where India has been losing. Of course, those who don t want to see, wouldn t see anything wrong in the picture.

Teen raped, asked to marry the accused when she turns 18 Now you may see the above headlines and feel it is ridiculous, but the fact is that these orders were put or given by Madras High Court couple of months back. This was then reported by both Livelaw and BarandBench respectively. Now to be truthful, this news didn t make much noise as it should have, probably as I had shared previously that the Govt. wants to lower the marriageable age to 15 or even less. And this is despite all the medical evidence on the contrary, because it assuages this Govt s masculinity. There is also the very recent case where the SC CJI asked the rapist if he is willing to marry a girl who was underage when she reaches maturity. Another one in which it seems martial rape is not a crime according to the CJI. So it seems these are the state of things in which India finds itself today. There are judges like Vrinda Grover who do question CJI but they are few and there are costs to them who ask questions. Although, as shared this news was overtaken by other news and would have remained so, if not one of the leaders of the present Govt. , a Ramesh Jarkiholi, who hails from Belagavi region of north Karnataka was caught in a sex CD scandal basically asking sexual favors for a permanent Govt. job. He had made statements after the Madras High Court case applauding the judgement given by the judge. While, due to public pressure he had to resign, but not before stating that he had everybody blue films including the Chief Minister of the State. And sad to report that six Karnataka Ministers rushed today or rather yesterday to put a petition in the civil court to restrain media from airing/printing/publishing any defamatory content against them. The court has granted a media gag against 68 media houses for the same. Sadly, the recent happening only reinforce what has been happening in Karnataka since a decade. Update 07/03/2021 Seems yesterday another 10 odd ministers rushed to get the same order. Seems different laws apply to politicians vis-a-vis others. A recent example of Rhea Chakravarthy, an actress and girlfriend of Sushant Singh who was hounded in his suicide case and many accusations made on TV but no evidence till date. From what we know as facts, Sushant committed suicide as he was not getting work due to cronyism in Bollywood. In fact, those who were behind it have white-washed themselves, deleted their tweets etc. and while the public knows, no accountability on them. In fact, there is and was so much that I wanted to share as to what has been happening to women, sadly and thankfully arre did the needful for me. They wrote an entire article which tells what the situation for women in India today is. And if you are wondering why I said, that is because when a site which was made exclusively for people to laugh and have a good time and get relief, when they start writing serious articles, you can be sure that things have gone horribly wrong

Asking Tesla to come to India and at the same time ambivalent on battery Recently, Mr. Nitin Gadkari, a prominent minister of the present Govt. invited Tesla and gave all sorts of incentives to start a manufacturing plant here in India. And while it seems that Tesla has accepted, looking at the Vodafone case, hopefully Tesla does make such contracts where if something goes wrong and they need to sue the Govt. they can do it in States or elsewhere. The way the Govt. acted in the Vodafone case had been a dampener to any MNC investments so far. Although to be fair to both Tesla and GOI, the basic models even if they are manufactured in India will go to less than 1% of the population. The cheapest Tesla Model Y which retails in the U.S. for USD 40k would be around INR 30 lakh. And this is their cheapest car to date. I do know there are rumors of the 25k but that is probably 2-3 years away as shared by Tesla China President Tom Zhu in an interview shared on YT.

https://www.youtube.com/watch?v=aH5leMWFBxI There are couple of interesting comments being made. The fact that China is going to fully open its automobile market to western companies shows how confident China feels about their own vendors. And I m not much impressed about Tesla as I am about the tiny car revolution happening in China. India, if it wanted to, could learn many lessons from China. Even the electric buses they had started in 2010 itself where people in our auto industry thought it was all a fad. Sadly, we are missing most of the technology and if and by the time Tesla starts a production line, dunno where we could get our lithium. India hasn t been as aggressive as other countries when it comes to securing raw natural resources in other countries, as some other countries have.  Even besides that, it has been tough when you have so many people who still believe that ICE vehicles (Internal Combustion Engines) are better than EV s and even if they know they choose to believe the propaganda. Couple of months ago a young UK girl who had died due to asthma, an inquest found that air pollution was a factor. The girl s name was Ella Adoo-Kissi-Debrah. This is the first case where the doctor ruled air pollution as a chief factor in a person s death. Probably first of its kind of ruling anywhere in the world. I also shared TCO studies between BEV and ICE vehicles done by people who are considering an electric vehicle but those studies seem to fall on deaf ears.

Starlink This is another of Elon Musk s ventures and would be a money spinner for sure in around the globe. While Starlink has asked TRAI for permission, I don t think they will get it. There is also Bharti Global s Oneweb which probably has a better chance of getting permissions. The reason is censorship. As shared above, India is now a leader in Internet shutdowns and do see this trend only accelerate rather than go the other way around. For people who don t remember, remember how satellite phones were made illegal even though only businessmen could afford it. And this was just 5 years ago. As shared Oneweb would have better shot as they would accept all Government directives without a second thought. Unless Starlink gives a binding to the Govt. to be a willing partner when it wants to have internet shutdowns, it will not work. Now how Elon approaches that is to be seen and known. FWIW, you can t access Starlink webpage on BSNL broadband. My broadband provider gives at the most 300 kbps and sometimes, at late nights or early mornings, around 500 kbps.

Farmer Protests
Lastly, farmer protests have entered 100 days. In the interim, Vivek Kaul, an economist took stock of the Bihar APMC to see if things have really worked as the Govt. supporters were telling. The investigation and the results didn t inspire the confidence as the Govt. said. The sad part is though, that nowadays nobody, at least those in power as well as those who are supporters are keen to read, understand and even argue otherwise. They are all happy with whatsapp knowledge. Till date 200+ people have died in the farmer protests. All mainstream media houses have stopped talking about farmers in the hope that they will disappear. At the end of the day the Govt. wants that the corporates should win at whatever the cost.

5 March 2021

Arturo Borrero Gonz lez: Openstack Neutron L3 failover issues

Networking In the Cloud Services team at the Wikimedia Foundation we use Openstack Neutron to build our virtual network, and in particular, we rely on the neutron-l3-agent for implementing all the L3 connectivity, topology and policing. This includes basic packet firewalling and NAT. As of this writing, we are using Openstack version Train. We run the neutron-l3-agent on standard linux hardware servers with 10G NICs, and in general it works really well. Our setup is rather simple: we have a couple of servers for redundancy (note: upstream recommends having 3) and each server runs an instance of neutron-l3-agent. We don t use DVR, so all ingress/egress network traffic (or north-south traffic) flows using these servers. Today we use a flat network topology in our cloud. This means that all of our virtual machines share the same router gateway. Therefore, we only have one software-defined router. Neutron does a very smart thing: each software-defined router is implemented on a linux network namespace (netns). Each router living on its own netns, the namespace contains all IP addresses, routes, interfaces, netfilter firewalling rules, NAT configuration, etc. Additionally, we configure the agents and software-defined routers to be deployed on an high availability fashion. Neutron implements this by running an instance of keepalived (VRRP) inside each router netns. The gateway IP is therefore a virtual address that can move between the two instances of the neutron-l3-agent. In our setup we rely very heavily on IPv4 NAT, we use it for the egress traffic (SNAT) and also for Openstack floating IPs (SNAT/DNAT). Neutron uses Netfilter rules for configuring the whole NAT setup. There is, however, no apparent mechanism in the neutron-l3-agent to ensure continuity of NATed TCP connections when a failover happens. If all NATed TCP connections are flowing using neutron-l3-agent node A, and a failover happens, node B wont be able to pick up the opened TCP streams and therefore all connections will need to be re-established. This happens because the conntrack information that Netfilter uses to perform NAT is not present in node B when the failover happens. NAT is, in general, a stateful thing and should be treated that way. It seems some folks upstream are aware of this, and there are even some blueprints to introduce conntrackd alongside keepalived. The actual implementation didn t happen so far, apparently. I wonder, are we the only cloud deployment suffering this issue? Our users have been experiencing annoying connection cuts every time we failover the neutron-l3-agent for whatever reason: an upgrade, server reboot, etc. After numerous incidents I opened a ticket in our phabricator instance and started working on it. I ve been trying to improve this situation by following a couple of strategies: To help the conntrack engine deal with NATed TCP connections I decided to try setting the sysctl key net.netfilter.nf_conntrack_tcp_be_liberal=1. But it turns out this sysctl key is not inherited from the main netns when the software-defined netns is created (i.e, is per-netns). I needed a mechanism to detect netns events (creation) and then inject the sysctl setting. Neutron apparently doesn t have any facility to hook/call commands at netns creation time. This felt like a very fun coding challenge, so I did it! I learned that netns have a /var/run/netns/<netns> entry, so I thought it would be easy to listen to file system events and react to them. I wanted to use some python, so I decided to go with the pyinotify library. I ended up creating a simple netns-events.py daemon/script. By using regexes it allows matching on netns names and running arbitrary commands on certain situations: The daemon reads a yaml configuration file like this:
---
# $NETNS env var is provided by the runner daemon
- netns_regex: ^qrouter-.*
  daemon_startup_actions:
    - ip netns exec $NETNS sysctl net.netfilter.nf_conntrack_tcp_be_liberal=1
    - ip netns exec $NETNS sysctl net.netfilter.nf_conntrack_tcp_loose=1
  inotify_actions:
    - IN_CREATE:
        - ip netns exec $NETNS sysctl net.netfilter.nf_conntrack_tcp_be_liberal=1
        - ip netns exec $NETNS sysctl net.netfilter.nf_conntrack_tcp_loose=1
We run this daemon as a systemd service, side by side with the neutron-l3-agent systemd service. Apparently the nf_conntrack_tcp_be_liberal sysctl key is only read either at module load time or netns creation time, so it is really important the netns-events.py daemon runs before neutron-l3-agent starts doing its thing. Anyway, this won t probably solve all of our problems. I m still on a massive rabbit hole with conntrackd, that I ll leave for another day. Other than this small script to set the sysctl keys I have more questions than answers. Again, I wonder what others do, or if there is something fundamentally wrong with our cloud network architecture. I ll keep researching how to deploy neutron-l3-agent in a more realiable fashion. If you have more hints, are in the same situation, or have any other insight, please let me know!

Sergio Durigan Junior: A debuginfod service for Debian

Hi there. Long time no write! On Tuesday, February 23, 2021, I made an announcement at debian-devel-announce about a new service that I configured for Debian: a debuginfod server. This post serves two purposes: pay the promise I made to Jonathan Carter that I would write a blog post about the service, and go into a bit more detail about it. What's debuginfod? From the announcement above:
debuginfod is a new-ish project whose purpose is to serve
ELF/DWARF/source-code information over HTTP.  It is developed under the
elfutils umbrella.  You can find more information about it here:
  https://sourceware.org/elfutils/Debuginfod.html
In a nutshell, by using a debuginfod service you will not need to
install debuginfo (a.k.a. dbgsym) files anymore; the symbols will be
served to GDB (or any other debuginfo consumer that supports debuginfod)
over the network.  Ultimately, this makes the debugging experience much
smoother (I myself never remember the full URL of our debuginfo
repository when I need it).
Perhaps not everybody knows this, but until last year I was a Debugger Engineer (a.k.a. GDB hacker) at Red Hat. I was not involved with the creation of debuginfod directly, but I witnessed discussions about "having way to serve debug symbols over the internet" multiple times during my tenure at the company. So this is not a new idea, and it's not even the first implementation, but it's the first time that some engineers actually got their hands dirty enough to have something concrete to show. The idea to set up a debuginfod server for Debian started to brew after 2019's GNU Tools Cauldron, but as usual several things happened in $LIFE (including a global pandemic and leaving Red Hat and starting a completely different job at Canonical) which had the effect of shuffling my TODO list "a little". Benefits for Debian Debian unfortunately is lagging behind when it comes to offer its users a good debugging experience. Before the advent of our debuginfod server, if you wanted to debug a package in Debian you would need to:
  1. Add the debian-debug apt repository to your /etc/apt/sources.list.
  2. Install the dbgsym package that contains the debug symbols for the package you are debugging. Note that the version of the dbgsym package needs to be exactly the same as the version of the package you want to debug.
  3. Figure out which shared libraries your package uses and install the dbgsym packages for all of them. Arguably, this step is optional but recommended if you would like to perform a more in-depth debugging.
  4. Download the package source, possibly using apt source or some equivalent command.
  5. Open GDB, and make sure you adjust the source paths properly (more below). This can be non-trivial.
  6. Finally, debug the program.
Now, with the new service, you will be able to start from step 4, without having to mess with sources.list, dbgsym packages and version mismatches. The package source It is important to mention an existing (but perhaps not well-known) limitation of our debugging experience in Debian: the need to manually download the source packages and adjust GDB to properly find them (see step 4 above). debuginfod is able to serve source code as well, but our Debian instance is not doing that at the moment. Debian does not provide a patched source tree that is ready to be consumed by GDB or debuginfod (for a good example of a distribution that does this, see Fedora's debugsource packages). Let me show you an example of debugging GDB itself (using debuginfod) on Debian:
$ HOME=/tmp DEBUGINFOD_URLS=https://debuginfod.debian.net gdb -q gdb
Reading symbols from gdb...
Downloading separate debug info for /tmp/gdb...
Reading symbols from /tmp/.cache/debuginfod_client/02046bac4352940d19d9164bab73b2f5cefc8c73/debuginfo...
(gdb) start
Temporary breakpoint 1 at 0xd18e0: file /build/gdb-Nav6Es/gdb-10.1/gdb/gdb.c, line 28.
Starting program: /usr/bin/gdb 
Downloading separate debug info for /lib/x86_64-linux-gnu/libreadline.so.8...
Downloading separate debug info for /lib/x86_64-linux-gnu/libz.so.1...
Downloading separate debug info for /lib/x86_64-linux-gnu/libncursesw.so.6...
Downloading separate debug info for /lib/x86_64-linux-gnu/libtinfo.so.6...
Downloading separate debug info for /tmp/.cache/debuginfod_client/d6920dbdd057f44edaf4c1fbce191b5854dfd9e6/debuginfo...
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Downloading separate debug info for /lib/x86_64-linux-gnu/libexpat.so.1...
Downloading separate debug info for /lib/x86_64-linux-gnu/liblzma.so.5...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libbabeltrace.so.1...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libbabeltrace-ctf.so.1...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libipt.so.2...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libmpfr.so.6...
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Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libxxhash.so.0...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libdebuginfod.so.1...
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Downloading separate debug info for /tmp/.cache/debuginfod_client/dbfea245d26065975b4084f4e9cd2d83c65973ee/debuginfo...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libdw.so.1...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libelf.so.1...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libuuid.so.1...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libgmp.so.10...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libboost_regex.so.1.74.0...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libcurl-gnutls.so.4...
Downloading separate debug info for /lib/x86_64-linux-gnu/libbz2.so.1.0...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libicui18n.so.67...
Downloading separate debug info for /tmp/.cache/debuginfod_client/acaa831dbbc8aa70bb2131134e0c83206a0701f9/debuginfo...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libicuuc.so.67...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libnghttp2.so.14...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libidn2.so.0...
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Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libssh2.so.1...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libpsl.so.5...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libnettle.so.8...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libgnutls.so.30...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libldap_r-2.4.so.2...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/liblber-2.4.so.2...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libbrotlidec.so.1...
Downloading separate debug info for /tmp/.cache/debuginfod_client/39739740c2f8a033de95c1c0b1eb8be445610b31/debuginfo...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libunistring.so.2...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libhogweed.so.6...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libgcrypt.so.20...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libp11-kit.so.0...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libtasn1.so.6...
Downloading separate debug info for /lib/x86_64-linux-gnu/libcom_err.so.2...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libsasl2.so.2...
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Downloading separate debug info for /lib/x86_64-linux-gnu/libgpg-error.so.0...
Downloading separate debug info for /usr/lib/x86_64-linux-gnu/libffi.so.7...
Downloading separate debug info for /lib/x86_64-linux-gnu/libkeyutils.so.1...
Temporary breakpoint 1, main (argc=1, argv=0x7fffffffebf8) at /build/gdb-Nav6Es/gdb-10.1/gdb/gdb.c:28
28      /build/gdb-Nav6Es/gdb-10.1/gdb/gdb.c: Directory not empty.
(gdb) list
23      in /build/gdb-Nav6Es/gdb-10.1/gdb/gdb.c
(gdb) 
(See all those Downloading separate debug info for... lines? Nice!) As you can see, when we try to list the contents of the file we're in, nothing shows up. This happens because GDB doesn't know where the file is. So you have to tell it. In this case, it's relatively easy: you see that the GDB package's build directory is /build/gdb-Nav6Es/gdb-10.1/. When you apt source gdb, you will end up with a directory called $PWD/gdb-10.1/ containing the full source of the package. Notice that the last directory's name in both paths is the same, so in this case we can use GDB's set substitute-path command do the job for us (in this example $PWD is /tmp/):
$ HOME=/tmp DEBUGINFOD_URLS=https://debuginfod.debian.net gdb -q gdb
Reading symbols from gdb...
Reading symbols from /tmp/.cache/debuginfod_client/02046bac4352940d19d9164bab73b2f5cefc8c73/debuginfo...
(gdb) set substitute-path /build/gdb-Nav6Es/ /tmp/
(gdb) start
Temporary breakpoint 1 at 0xd18e0: file /build/gdb-Nav6Es/gdb-10.1/gdb/gdb.c, line 28.
Starting program: /usr/bin/gdb 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Temporary breakpoint 1, main (argc=1, argv=0x7fffffffebf8) at /build/gdb-Nav6Es/gdb-10.1/gdb/gdb.c:28
warning: Source file is more recent than executable.
28        memset (&args, 0, sizeof args);
(gdb) list
23      int
24      main (int argc, char **argv)
25       
26        struct captured_main_args args;
27
28        memset (&args, 0, sizeof args);
29        args.argc = argc;
30        args.argv = argv;
31        args.interpreter_p = INTERP_CONSOLE;
32        return gdb_main (&args);
(gdb)
Much better, huh? The problem is that this process is manual, and changes depending on how the package you're debugging was built. What can we do to improve this? What I personally would like to see is something similar to what the Fedora project already does: create a new debug package which will contain the full, patched source package. This would mean changing our building infrastructure and possibly other somewhat complex things. Using the service (by default) At the time of this writing, I am working on an elfutils Merge Request whose purpose is to implement a debconf question to ask the user whether she wants to use our service by default. If you would like to start using the service right now, all you have to do is set the following environment variable in your shell:
DEBUGINFOD_URLS="https://debuginfod.debian.net"
More information You can find more information about our debuginfod service here. Try to keep an eye on the page as it's being constantly updated. If you'd like to get in touch with me, my email is my domain at debian dot org. I sincerely believe that this service is a step in the right direction, and hope that it can be useful to you :-).

4 March 2021

Gunnar Wolf: The power of EIDE

I am quite happy with the Raspberry tower I bought for keeping my Raspberries organized. Clustering them? No, not by a long shot. I just want to quickly know where they all are, and at a glance, be able to know which one I will work with. Bottom drawer has a RPi1B, second one has a RPi2, next comes a 3B+, and the top two ones are RPi4 (4 and 8GB). That allows me for quick testing of stuff. Yes, I am tempted to get the top one out of the array and use it in production but as it stands, that s the layout. My only quip with this? Serial console access. Connecting and releasing the three tiny cables (no, the red one is not required it provides +5V power, but it s not enough to power over USB more than the earliest RPis) with my big, fat and numb fingers Always takes a minute or three. Until I thought of the obvious: Why not connect the RPi headers to an old EIDE cable? They are of the same dimensions, and much more practical to connect and yank! with that interface expansion in place, I will be able to easily connect my console cables Or even more, I can put on a serious electronic look on my face, take out my soldering iro ehem my very small breadboard for those with limited abilities, and look more interesting! In fact, I am almost sure I can get these two little buggers to blink interestingly when bytes come and go to my RPis! I will finally gain a bit of self-respect as an electronic tinkerer! (yes, yes, I enjoy playing with RPis, but I treat them as Well Computers. I don t do interfacing to the real world, although I m sure it can be fun) What stopped me from doing so? Pin 20 of the EIDE specification. As a service to clumsy computer repairers such as myself, the standard specifies pin 20 is not to carry any signals, and the drive headers are to ship it cut (Key, pin missing), so that together with the notch on the outer part of the bracket inserting the cable upside down is physically impossible. So no, I m not able to finish the project with pieces at hand. I even went to two nearby electronic shops yesterday when I took my dog out for a walk, and could not find it there either So I ended up buying what appears to be a sweet, cheap product covering my needs from our corporate capitalist overlords.

Molly de Blanc: Vaccination

This is about why I decided to get vaccinated, and why that was a hard choice. Note: If you have the opportunity to get vaccinated, you should. This is good for public health. If you re worried about being a bad person by getting vaccinated now, you re probably not a bad person. This is my professional opinion as a bioethics graduate student. Anyway, onward. Not Great Reasons to Not Get Vaccinated Reason one: Other people need them more. There are people have a much higher risk of dying from COVID or having long term consequences. I don t want to get a vaccine at the expense of someone who has much worse projected outcomes. Reason two: I live a lowish risk life. I have a low/medium risk lifestyle. I go to the grocery store, but I don t do things like indoor dining. I have drinks with friends, outside, generally maintaining distance and trying to be polite and careful. I go on walks or sit in parks with friends. I have three people I see inside, and we don t see anyone else inside. Through my school, I am tested regularly though I am behind right now, I ll admit. I work from home, I take classes on my computer. My podmates also work from home. There are other people who live much higher risk lives and don t have a choice in the matter. They work outside of their homes, they are taking care of other people, they re incarcerated, their children go to school in-person. Those people need vaccines more than I do or at least I feel like that s the case. Even though I know that, e.g., parents won t be able to get vaccinated unless they otherwise qualify, I still feel like I d be doing them wrong by getting vaccinated first! Reason three: I don t want to deal with other people s judgement. When New Jersey allowed smokers to get vaccinated, wow, did people go off on how unfair that is. I ve seen the same rhetoric applied to other preexisting conditions/qualifications. Boo. Great Reasons to Get Vaccinated I had a few good conversations with friends I respect a lot. They convinced me that I should get vaccinated, in spite of my concerns. Reason one: I m scared of COVID. I actually find this the weakest of my reasons to get vaccinated: I m scared of COVID. I get migraines. I downplay how bad they are, because I know other people who have it worse, but they re terrible. They re debilitating. COVID can increase your risk of migraines, especially if you re already prone to them. They can last months. Boo. I m terrified of Long COVID. A part of my identity comes from doing things outside, and this past year without regularly swimming or going on bike trips or going up mountains has been really rough for me. For my own sake, I don t want to get sick. Reason two: I want to protect the people in my life. Being vaccinated is good for the people in my life. The current conversation I ve heard is that if you re vaccinated, you re probably less likely to spread COVID to those around you. That sounds great! I m not going to change my lifestyle anytime soon to be higher risk, but I like knowing that there s an even smaller chance I will become a disease vector. Reason three: Seriously, everyone should get vaccinated. Vaccinations are key to fighting COVID. I am not an epidemiologist (though I did once consider become an epistemologist). I m not going to pretend to be one. But they tell me that vaccines are really important, and the Intro to Public Health class I took agrees. We need to vaccinate everyone we can, everywhere in the world, in order to create the best outcomes. We don t want some vaccine-resistant COVID variant to show up somewhere because we were jerkfaces and prevented people from getting vaccinated. Medical professionals and experts I talked with told me to get vaccinated as soon as the opportunity arose. Maybe they said this because they like me, but I think they re also concerned about public health. So you re ready to get your vaccine! I m so excited for you! Sumana Harihareswara wrote this great blog post about getting vaccinated in New York City, though is probably relevant for New York State in general. Please check out your state s guidelines and maybe do a little research or creative thinking about what counts. This Twitter thread Sumana shared talked about ADHD as a qualifying condition under developmental and learning disorders. Your doctor might be super helpful! Your doctor might also not be helpful at all. When I talked to mine they didn t know much about the vaccine roll out plan, criteria, or procedures around proof of medical condition. Some vaccine sites also have waitlists for extra doses. A friend of mine is on one! For these, you generally don t have to meet the qualification criteria. These are doses left at the end of the day due to canceled appointments and things like that. A lot of states have useful Twitter bots and web sites. We have TurboVax. It s great. Big fan. These are usually appoints for the day of or the next day or two.

2 March 2021

Russ Allbery: Review: The Lion, the Witch and the Wardrobe

Review: The Lion, the Witch and the Wardrobe, by C.S. Lewis
Illustrator: Pauline Baynes
Series: Chronicles of Narnia #1
Publisher: Collier Books
Copyright: 1950
Printing: 1978
ISBN: 0-02-044220-3
Format: Mass market
Pages: 186
Although it's been more than 20 years since I last read it, I believe I have read The Lion, the Witch and the Wardrobe more times than any other book. The count is certainly in double digits. As you might guess, I also have strong opinions about it, some of which are unorthodox, and I've been threatening to write this review for years. It seemed a fitting choice for my 1000th review. There is quite a lot that can and has been said about this book and this series, and this review is already going to be much too long, so I'm only going to say a fraction of it. I'm going to focus on my personal reactions as someone raised a white evangelical Christian but no longer part of that faith, and the role this book played in my religion. I'm not going to talk much about some of its flaws, particularly Lewis's treatment of race and gender. This is not because I don't agree they're there, but only that I don't have much to say that isn't covered far better in other places. Unlike my other reviews, this one will contain major spoilers. If you have managed to remain unspoiled for a 70-year-old novel that spawned multiple movies and became part of the shared culture of evangelical Christianity, and want to stay that way, I'll warn you in ALL CAPS when it's time to go. But first, a few non-spoiler notes. First, reading order. Most modern publications of The Chronicles of Narnia will list The Magician's Nephew as the first book. This follows internal chronological order and is at C.S. Lewis's request. However, I think Lewis was wrong. You should read this series in original publication order, starting with The Lion, the Witch and the Wardrobe (which I'm going to abbreviate as TLtWatW like everyone else who writes about it). I will caveat this by saying that I have a bias towards reading books in the order an author wrote them because I like seeing the development of the author's view of their work, and I love books that jump back in time and fill in background, so your experience may vary. But the problem I see with the revised publication order is that The Magician's Nephew explains the origins of Narnia and, thus, many of the odd mysteries of TLtWatW that Lewis intended to be mysterious. Reading it first damages both books, like watching a slow-motion how-to video for a magic trick before ever seeing it performed. The reader is not primed to care about the things The Magician's Nephew is explaining, which makes it less interesting. And the bits of unexpected magic and mystery in TLtWatW that give it so much charm (and which it needs, given the thinness of the plot) are already explained away and lose appeal because of it. I have read this series repeatedly in both internal chronological order and in original publication order. I have even read it in strict chronological order, wherein one pauses halfway through the last chapter of TLtWatW to read The Horse and His Boy before returning. I think original publication order is the best. (The Horse and His Boy is a side story and it doesn't matter that much where you read it as long as you read it after TLtWatW. For this re-read, I will follow original publication order and read it fifth.) Second, allegory. The common understanding of TLtWatW is that it's a Christian allegory for children, often provoking irritated reactions from readers who enjoyed the story on its own terms and later discovered all of the religion beneath it. I think this view partly misunderstands how Lewis thought about the world and there is a more interesting way of looking at the book. I'm not as dogmatic about this as I used to be; if you want to read it as an allegory, there are plenty of carefully crafted parallels to the gospels to support that reading. But here's my pitch for a different reading. To C.S. Lewis, the redemption of the world through the death of Jesus Christ is as foundational a part of reality as gravity. He spent much of his life writing about religion and Christianity in both fiction and non-fiction, and this was the sort of thing he constantly thought about. If somewhere there is another group of sentient creatures, Lewis's theology says that they must fit into that narrative in some way. Either they would have to be unfallen and thus not need redemption (roughly the position taken by The Space Trilogy), or they would need their own version of redemption. So yes, there are close parallels in Narnia to events of the Christian Bible, but I think they can be read as speculating how Christian salvation would play out in a separate creation with talking animals, rather than an attempt to disguise Christianity in an allegory for children. It's a subtle difference, but I think Narnia more an answer to "how would Christ appear in this fantasy world?" than to "how do I get children interested in the themes of Christianity?", although certainly both are in play. Put more bluntly, where other people see allegory, I see the further adventures of Jesus Christ as an anthropomorphic lion, which in my opinion is an altogether more delightful way to read the books. So much for the preamble; on to the book. The Pevensie kids, Peter, Susan, Edmund, and Lucy, have been evacuated to a huge old house in the country due to the air raids (setting this book during World War II, something that is passed over with barely a mention and not a hint of trauma in a way that a modern book would never do). While exploring this house, which despite the scant description is still stuck in my mind as the canonical huge country home, Lucy steps into a wardrobe because she wants to feel the fur of the coats. Much to her surprise, the wardrobe appears not to have a back, and she finds herself eventually stepping into a snow-covered pine forest where she meets a Fawn named Mr. Tumnus by an unlikely lamp-post. MAJOR SPOILERS BELOW, so if you don't want to see those, here's your cue to stop reading. Two things surprised me when re-reading TLtWatW. The first, which I remember surprising me every time I read it, is how far into this (very short) book one has to go before the plot kicks into gear. It's not until "What Happened After Dinner" more than a third in that we learn much of substance about Narnia, and not until "The Spell Begins to Break" halfway through the book that things start to happen. The early chapters are concerned primarily with the unreliability of the wardrobe portal, with a couple of early and brief excursions by Edmund and Lucy, and with Edmund being absolutely awful to Lucy. The second thing that surprised me is how little of what happens is driven by the kids. The second half of TLtWatW is about the fight between Aslan and the White Witch, but this fight was not set off by the children and their decisions don't shape it in any significant way. They're primarily bystanders; the few times they take action, it's either off-camera or they're told explicitly what to do. The arguable exception is Edmund, who provides the justification for the final conflict, but he functions more as plot device than as a character with much agency. When that is combined with how much of the story is also on rails via its need to recapitulate part of the gospels (more on that in a moment), it makes the plot feel astonishingly thin and simple. Edmund is the one protagonist who gets to make some decisions, all of them bad. As a kid, I hated reading these parts because Edmund is an ass, the White Witch is obviously evil, and everyone knows not to eat the food. Re-reading now, I have more appreciation for how Lewis shows Edmund's slide into treachery. He starts teasing Lucy because he thinks it's funny (even though it's not), has a moment when he realizes he was wrong and almost apologizes, but then decides to blame his discomfort on the victim. From that point, he is caught, with some help from the White Witch's magic, in a spiral of doubling down on his previous cruelty and then feeling unfairly attacked. Breaking the cycle is beyond him because it would require admitting just how badly he behaved and, worse, that he was wrong and his little sister was right. He instead tries to justify himself by spreading poisonous bits of doubt, and looks for reasons to believe the friends of the other children are untrustworthy. It's simplistic, to be sure, but it's such a good model of how people slide into believing conspiracy theories and joining hate groups. The Republican Party is currently drowning in Edmunds. That said, Lewis does one disturbing thing with Edmund that leaped out on re-reading. Everyone in this book has a reaction when Aslan's name is mentioned. For the other three kids, that reaction is awe or delight. For Edmund, it's mysterious horror. I know where Lewis is getting this from, but this is a nasty theological trap. One of the problems that religion should confront directly is criticism that questions the moral foundations of that religion. If one postulates that those who have thrown in with some version of the Devil have an instinctual revulsion for God, it's a free intellectual dodge. Valid moral criticism can be hand-waved away as Edmund's horrified reaction to Aslan: a sign of Edmund's guilt, rather than a possible flaw to consider seriously. It's also, needless to say, not the effect you would expect from a god who wants universal salvation! But this is only an odd side note, and once Edmund is rescued it's never mentioned again. This brings us to Aslan himself, the Great Lion, and to the heart of why I think this book and series are so popular. In reinterpreting Christianity for the world of Narnia, Lewis created a far more satisfying and relatable god than Jesus Christ, particularly for kids. I'm not sure I can describe, for someone who didn't grow up in that faith, how central the idea of a personal relationship with Jesus is to evangelical Christianity. It's more than a theological principle; it's the standard by which one's faith is judged. And it is very difficult for a kid to mentally bootstrap themselves into a feeling of a personal relationship with a radical preacher from 2000 years ago who spoke in gnomic parables about subtle points of adult theology. It's hard enough for adults with theological training to understand what that phrase is intended to mean. For kids, you may as well tell them they have a personal relationship with Aristotle. But a giant, awe-inspiring lion with understanding eyes, a roar like thunder, and a warm mane that you can bury your fingers into? A lion who sacrifices himself for your brother, who can be comforted and who comforts you in turn, and who makes a glorious surprise return? That's the kind of god with which one can imagine having a personal relationship. Aslan felt physical and embodied and present in the imagination in a way that Jesus never did. I am certain I was not the only Christian kid for whom Aslan was much more viscerally real than Jesus, and who had a tendency to mentally substitute Aslan for Jesus in most thoughts about religion. I am getting ahead of myself a bit because this is a review of TLtWatW and not of the whole series, and Aslan in this book is still a partly unformed idea. He's much more mundanely present here than he is later, more of a field general than a god, and there are some bits that are just wrong (like him clapping his paws together). But the scenes with Susan and Lucy, the night at the Stone Table and the rescue of the statues afterwards, remain my absolute favorite parts of this book and some of the best bits of the whole series. They strike just the right balance of sadness, awe, despair, and delight. The image of a lion also lets Lewis show joy in a relatable way. Aslan plays, he runs, he wrestles with the kids, he thrills in the victory over evil just as much as Susan and Lucy do, and he is clearly having the time of his life turning people back to flesh from stone. The combination of translation, different conventions, and historical distance means the Bible has none of this for the modern reader, and while people have tried to layer it on with Bible stories for kids, none of them (and I read a lot of them) capture anything close to the sheer joy of this story. The trade-off Lewis makes for that immediacy is that Aslan is a wonderful god, but TLtWatW has very little religion. Lewis can have his characters interact with Aslan directly, which reduces the need for abstract theology and difficult questions of how to know God's will. But even when theology is unavoidable, this book doesn't ask for the type of belief that Christianity demands. For example, there is a crucifixion parallel, because in Lewis's world view there would have to be. That means Lewis has to deal with substitutionary atonement (the belief that Christ died for the sins of the world), which is one of the hardest parts of Christianity to justify. How he does this is fascinating. The Narnian equivalent is the Deep Magic, which says that the lives of all traitors belong to the White Witch. If she is ever denied a life, Narnia will be destroyed by fire and water. The Witch demands Edmund's life, which sets up Aslan to volunteer to be sacrificed in Edmund's place. This triggers the Deeper Magic that she did not know about, freeing Narnia from her power. You may have noticed the card that Lewis is palming, and to give him credit, so do the kids, leading to this exchange when the White Witch is still demanding Edmund:
"Oh, Aslan!" whispered Susan in the Lion's ear, "can't we I mean, you won't, will you? Can't we do something about the Deep Magic? Isn't there something you can work against it?" "Work against the Emperor's magic?" said Aslan, turning to her with something like a frown on his face. And nobody ever made that suggestion to him again.
The problem with substitutionary atonement is why would a supposedly benevolent god create such a morally abhorrent rule in the first place? And Lewis totally punts. Susan is simply not allowed to ask the question. Lewis does try to tackle this problem elsewhere in his apologetics for adults (without, in my opinion, much success). But here it's just a part of the laws of this universe, which all of the characters, including Aslan, have to work within. That leads to another interesting point of theology, which is that if you didn't already know about the Christian doctrine of the trinity, you would never guess it from this book. The Emperor-Beyond-the-Sea and Aslan are clearly separate characters, with Aslan below the Emperor in the pantheon. This makes rules like the above work out more smoothly than they do in Christianity because Aslan is bound by the Emperor's rules and the Emperor is inscrutable and not present in the story. (The Holy Spirit is Deity Not-appearing-in-this-book, but to be fair to Lewis, that's largely true of the Bible as well.) What all this means is that Aslan's death is presented straightforwardly as a magic spell. It works because Aslan has the deepest understanding of the fixed laws of the Emperor's magic, and it looks nothing like what we normally think of as religion. Faith is not that important in this book because Aslan is physically present, so it doesn't require any faith for the children to believe he exists. (The Beavers, who believed in him from prophecy without having seen him, are another matter, but this book never talks about that.) The structure of religion is therefore remarkably absent despite the story's Christian parallels. All that's expected of the kids is the normal moral virtues of loyalty and courage and opposition to cruelty. I have read this book so many times that I've scrutinized every word, so I have to resist the temptation to dig into every nook and cranny: the beautiful description of spring, the weird insertion of Lilith as Adam's first wife, how the controversial appearance of Santa Claus in this book reveals Lewis's love of Platonic ideals... the list is endless, and the review is already much longer than normal. But I never get to talk about book endings in reviews, so one more indulgence. The best thing that can be said about the ending of TLtWatW is that it is partly redeemed by the start of Prince Caspian. Other than that, the last chapter of this book has always been one of my least favorite parts of The Chronicles of Narnia. For those who haven't read it (and who by this point clearly don't mind spoilers), the four kids are immediately and improbably crowned Kings and Queens of Narnia. Apparently, to answer the Professor from earlier in the book, ruling magical kingdoms is what they were teaching in those schools? They then spend years in Narnia, never apparently giving a second thought to their parents (you know, the ones who are caught up in World War II, which prompted the evacuation of the kids to the country in the first place). This, for some reason, leaves them talking like medieval literature, which may be moderately funny if you read their dialogue in silly voices to a five-year-old and is otherwise kind of tedious. Finally, in a hunt for the white stag, they stumble across the wardrobe and tumble back into their own world, where they are children again and not a moment has passed. I will give Lewis credit for not doing a full reset and having the kids not remember anything, which is possibly my least favorite trope in fiction. But this is almost as bad. If the kids returned immediately, that would make sense. If they stayed in Narnia until they died, that arguably would also make sense (their poor parents!). But growing up in Narnia and then returning as if nothing happened doesn't work. Do they remember all of their skills? How do you readjust to going to school after you've lived a life as a medieval Queen? Do they remember any of their friends after fifteen years in Narnia? Argh. It's a very "adventures are over, now time for bed" sort of ending, although the next book does try to patch some of this up. As a single book taken on its own terms, TLtWatW is weirdly slight, disjointed, and hits almost none of the beats that one would expect from a children's novel. What saves it is a sense of delight and joy that suffuses the descriptions of Narnia, even when locked in endless winter, and Aslan. The plot is full of holes, the role of the children in that plot makes no sense, and Santa Claus literally shows up in the middle of the story to hand out plot devices and make an incredibly sexist statement about war. And yet, I memorized every gift the children received as a kid, I can still feel the coziness of the Beaver's home while Mr. Beaver is explaining prophecy, and the night at the Stone Table remains ten times more emotionally effective for me than the description of the analogous event in the Bible. And, of course, there's Aslan.
"Safe?" said Mr. Beaver. "Don't you hear what Mrs. Beaver tells you? Who said anything about safe? 'Course he isn't safe. But he's good. He's the king, I tell you."
Aslan is not a tame lion, to use the phrase that echos through this series. That, I think, is the key to the god that I find the most memorable in all of fantasy literature, even in this awkward, flawed, and decidedly strange introduction. Followed by Prince Caspian, in which the children return to a much-changed Narnia. Lewis has gotten most of the obligatory cosmological beats out of the way in this book, so subsequent books can tell more conventional stories. Rating: 7 out of 10

1 March 2021

Russ Allbery: Review: Architects of Memory

Review: Architects of Memory, by Karen Osborne
Series: Memory War #1
Publisher: Tor
Copyright: 2020
ISBN: 1-250-21546-3
Format: Kindle
Pages: 350
Ash is an Aurora Company indenture working as a salvage pilot in the wreckage of the Battle of Tribulation. She's been on the crew of the Twenty-Five and indentured to Aurora for about a year. Before that, she was an indenture in the mines of Bittersweet, where her fianc died in an attack from the alien Vai and where she contracted the celestium poisoning that's slowly killing her. Her only hope for treatment is to work off her indenture and become a corporate citizen, a hope that is doomed if Aurora discovers her illness. Oh, and she's in love with the citizen captain of the Twenty-Five, a relationship that's a bad idea for multiple reasons and which the captain has already cut off. This is the hopeful, optimistic part of the book, before things start getting grim. The setting of Architects of Memory is a horrifying future of corporate slavery and caste systems that has run head-long into aliens. The Vai released mysterious and beautiful weapons that kill humans horribly and were wreaking havoc on the corporate ships, but then the Vai retreated in the midst of their victory. The Twenty-Five is salvaging useful equipment and undetonated Vai ordnance off the dead hulk of the Aurora ship London when corporate tells them that the London may be hiding a more potent secret: a captured Vai weapon that may be the reason the Vai fled. I was tempted into reading this because the plot is full of elements I usually like: a tight-knit spaceship crew, alien first contact full of mysterious discoveries, corporate skulduggery, and anti-corporate protagonists. However, I like those plot elements when they support a story about overthrowing oppression and improving the universe. This book, instead, is one escalating nightmare after another. Ash starts the book sick but functional and spends much of the book developing multiple forms of brain damage. She's not alone; the same fate awaits several other likable characters. The secret weapon has horrible effects while also being something more terrible than a weapon. The corporations have an iron and apparently inescapable grip on humanity, with no sign of even the possibility of rebellion, and force indentures to cooperate with their slavery in ways that even the protagonists can't shake. And I haven't even mentioned the organ harvesting and medical experiments. The plot is a spiral between humans doing awful things to aliens and then doing even more awful things to other humans. I don't want to spoil the ending, but I will say that it was far less emotionally satisfying than I needed. I'm not sure this was intentional; there are some indications that Osborne meant for it to be partly cathartic for the characters. But not only didn't it work for me at all, it emphasized my feelings about the hopelessness and futility of the setting. If a book is going to put me through that amount of character pain and fear, I need a correspondingly significant triumph at the end. If that doesn't bother you as much as it does me, this book does have merits. The descriptions of salvage on a disabled starship are vivid and memorable and a nice change of pace from the normal military or scientific space stories. Salvage involves being careful, methodical, and precise in the face of tense situations; combined with the eerie feeling of battlefield remnants, it's an evocative scene. The Vai devices are satisfyingly alien, hitting a good balance between sinister and exotically beautiful. The Vai themselves, once we finally learn something about them, are even better: a truly alien form of life at the very edge of mutual understanding. There was the right amount of inter-corporate skulduggery, with enough factions for some tense complexity and double-crossing, but not so many that I lost track. And there is some enjoyably tense drama near the climax. Unfortunately, the unremitting horrors were too much for me. They're also too much for the characters, who oscillate between desperate action and psychological meltdowns that become more frequent and more urgently described as one gets farther into the book. Osborne starts the book with the characters already so miserable that this constant raising of the stakes became overwrought and exhausting for me. By the end of the book, the descriptions of the mental state of the characters felt like an endless, incoherent scream of pain. Combine that with a lot of body horror, physical and mental illness, carefully-described war crimes, and gruesome death, and I hit mental overload. This is not the type of science fiction novel (thankfully getting rarer) in which the author thinks any of these things are okay. Osborne is clearly on the side of her characters and considers the events of this story as horrible as I do. I think her goal was to tell a story about ethics and courage in the face of atrocities and overwhelming odds, and maybe another reader would find that. For me, it was lost in the darkness. Architects of Memory reaches a definite conclusion but doesn't resolve some major plot elements. It's followed by Engines of Oblivion, which might, based on the back-cover text, be more optimistic? I don't think I have it in me to find out, though. Rating: 4 out of 10

Ben Hutchings: Debian LTS work, January/February 2021

In January was assigned 7 hours of work by Freexian's Debian LTS initiative and carried over 8.5 hours from earlier months. However, I only used 0.25 hours of these to write December's report. In Feburary I was assigned another 16 hours to work, and have worked 19 hours. I will carry over the remaining hours to March. I uploaded a Linux 4.19 package update based on the recent security update for Debian 10 "buster", and issued DLA-2557-1 for this. I spent most of my time working on an update for Linux 4.9. However, some of the recent security fixes are not yet in a fully working state, so I have not been able to upload an update yet.

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