|
|
With the recent resurgence in Covid19 I’ve been working from home a lot and using both my work laptop and personal PC on the same monitor. HDMI KVM switches start at $150 and I didn’t feel like buying one. So I wrote a script to change inputs on my monitor. The following script locks the session on the local machine and switches the monitor’s input to the other machine. I ran the command “ddcutil vcpinfo| grep Input” which shows that (on my monitor at least) 60 is the VCP for input. Then I ran the command “ddcutil getvcp 60” to get the current value and tried setting values sequentially to find the value for the other port.
Below is the script I’m using on one system, the other is the same but setting the different port via setvcp. The loginctl command is to lock the screen to prevent accidental keyboard or mouse input from messing anything up.
# lock the session, assumes that seat0 is the only session
loginctl lock-session $(loginctl list-sessions|grep "seat0 *$"|cut -c1-7)
# 0xf is DisplayPort, 0x11 is HDMI-1
ddcutil setvcp 60 0x11
For keyboard, mouse, and speakers I’m using a USB 2.0 hub that I can switch between computers. I idly considered getting a three-pole double-throw switch (four pole switches aren’t available at my local electronic store) to switch USB 2.0 as I only need to switch 3 of the 4 wires. But for the moment just plugging the hub into different systems is enough, I only do that a couple of times a day.
Google did some interesting research on the impact of discrimination on code reviers [1]. It turns out that this is a bigger problem than most white men would have ever suspected and it even has an adverse effect on Asian people.
nothello.net is an amusing site to make the point that you shouldn’t use IM to say hello separately from asking the question [2]. A good link to share on your corporate IM system.
TechCrunch has an amusing article about the Facebook farewell to Sheryl Sandburg [3].
BleepingComputer has an interesting article about a bug-bunty program from a crime syndicate offering up to $1M in crypto-currency [4]. Among other things finding the real first and last names of the crime lord gets you $1M.
BleepingComputer has an interesting article about how “deepfakes” are being used to apply for work from home jobs [5]. I wonder whether the people doing that intend to actually do any of the work or just get paid for doing nothing while delaying getting sacked for as long as possible. I have read about people getting a job they don’t want to do that has a long training period so that they can quit at the end of training without working – apparently call center work is a good option for this.
BleepingComputer has an interesting article about phishing attacks that use a VNC remote desktop connection to trick a user into authenticating using the attacker’s PC [6]. The real problem here is getting humans to do things that computers do better, which is recognising the correct foreign party.
Fortune has an interesting article about the problems with Tesla self-driving and the possibility of a recall [7]. The main issue is apparently Teslas driving at full speed into emergency services vehicles that are parked while attending an incident. Having a police car unexpectedly occupying a lane of traffic is something you just have to deal with, either stop or change lanes. Teslas have been turning off autopilot less than one second before impact so Telsa can claim that it didn’t happen with autopilot engaged but in reality a human can’t take over in less than one second, a pilot I know says it takes 2-3 seconds to take over the controls in a plane.
BonAppetit has an interesting and amusing article about protest foods [8] which starts by explaining why Ukrainians are throwing pasta at the Russian consulate.
The NVidia blog has an informative post about how Pony.ai optimised their pipeline for sensor data for autonomous cars [9].
Matt Crump wrote an educational and amusing blog post about his battle with cheaters in university tests he administered [10].
The Cricket Monthly has an insightful article about how a batsman manages to see and hit a cricket ball that’s going well in excess of 100KM/h [11]. One particularly noteworthy part of this article is the comparison of what amateur cricketers do with what anyone who wants to be a contender for the national team must do.
Darker Shades of Blue is an insightful paper by Tony Kern about the needless crash of a B52 at Fairchild air base in 1994 [12]. This is specifically written to teach people about correct and effective leadership.
I have just returned a Philips 438P1 43″ 4K Monitor [1] and gone back to my Samsung 28″ 4K monitor model LU28E590DS/XY AKA UE590.
The main listed differences are the size and the fact that the Samsung is TN but the Philips is IPS. Here’s a comparison of TN and IPS technologies [2]. Generally I think that TN is probably best for a monitor but in theory IPS shouldn’t be far behind.
The Philips monitor has a screen with a shiny surface which may be good for a TV but isn’t good for a monitor. Also it seemed to blur the pixels a bit which again is probably OK for a TV that is trying to emulate curved images but not good for a monitor where it’s all artificial straight lines. The most important thing for me in a monitor is how well it displays text in small fonts, for that I don’t really want the round parts of the letters to look genuinely round as a clear octagon or rectangle is better than a fuzzy circle.
There is some controversy about the ideal size for monitors. Some people think that nothing larger than 28″ is needed and some people think that a 43″ is totally usable. After testing I determined that 43″ is really too big, I had to move to see it all. Also for my use it’s convenient to be able to turn a monitor slightly to allow someone else to get a good view and a 43″ monitor is too large to move much (maybe future technology for lighter monitors will change this).
Previously I had been unable to get my Samsung monitor to work at 4K resolution with 60Hz and had believed it was due to cheap video cards. I got the Philips monitor to work with HDMI so it’s apparent that the Samsung monitor doesn’t do 4K@60Hz on HDMI. This isn’t a real problem as the Samsung monitor doesn’t have built in speakers. The Philips monitor has built in speakers for HDMI sound which means one less cable to my PC and no desk space taken by speakers.
I bought the Philips monitor on eBay in “opened unused” condition. Inside the box was a sheet with a printout stating that the monitor blanks the screen periodically, so the seller knew that it wasn’t in unused condition, it was tested and failed the test. If the Philips monitor had been as minimally broken as described then I might have kept it. However it seems that certain patterns of input caused it to reboot. For example I could be watching Netflix and have it drop out, I would press the left arrow to watch that bit again and have it drop out again. On one occasion I did a test and found that a 5 second section of Netflix content caused the monitor to reboot on 6/8 times I viewed it. The workaround I discovered was to switch between maximised window and full-screen mode when it had a dropout. So I just press left-arrow and then ‘F’ and I can keep watching. That’s not what I expect from a $700 monitor!
I considered checking for Philips firmware updates but decided against it because I didn’t want to risk voiding the warranty if it didn’t work correctly and I decided I just didn’t like the monitor that much.
Ideally for my next monitor I’ll get a 4K screen of about 35″, TN, and a screen that’s not shiny. At the moment there doesn’t seem to be many monitors between 32″ and 43″ in size, so 32″ may do. I am quite happy with the Samsung monitor so getting the same but slightly larger is fine. It’s a pity they stopped making 5K displays.
Elon Musk has made the news for spending billions to buy a share of Twitter for the alleged purpose of providing free speech. The problem with this claim is that having any company controlling a large portion of the world’s communication is inherently bad for free speech. The same applies for Facebook, but that’s not a hot news item at the moment.
If Elon wanted to provide free speech he would want to have decentralised messaging systems so that someone who breaks rules on one platform could find another with different rules. Among other things free speech ideally permits people to debate issues with residents of another country on issues related to different laws. If advocates for the Russian government get kicked off Twitter as part of the American sanctions against Russia then American citizens can’t debate the issue with Russian citizens via Twitter. Mastodon is one example of a federated competitor to Twitter [1]. With a federated messaging system each host could make independent decisions about interpretation of sanctions. Someone who used a Mastodon instance based in the US could get a second account in another country if they wanted to communicate with people in countries that are sanctioned by the US.
The problem with Mastodon at the moment is lack of use. It’s got a good set of features and support for different platforms, there are apps for Android and iPhone as well as lots of other software using the API. But if the people you want to communicate with aren’t on it then it’s less useful. Elon could solve that problem by creating a Tesla Mastodon server and give a free account to everyone who buys a new Tesla, which is the sort of thing that a lot of Tesla buyers would like. It’s quite likely that other companies selling prestige products would follow that example. Everyone has seen evidence of people sharing photos on social media with someone else’s expensive car, a Mastodon account on ferrari.com or mercedes.com would be proof of buying the cars in question. The number of people who buy expensive cars new is a very small portion of the world population, but it’s a group of people who are more influential than average and others would join Mastodon servers to follow them.
The next thing that Elon could do to kill Twitter would be to have all his companies (which have something more than a dozen verified Twitter accounts) use Mastodon accounts for their primary PR releases and then send the same content to Twitter with a 48 hour delay. That would force journalists and people who want to discuss those companies on social media to follow the Mastodon accounts. Again this wouldn’t be a significant number of people, but they would be influential people. Getting journalists to use a communications system increases it’s importance.
The question is whether Elon is lacking the vision necessary to plan a Mastodon deployment or whether he just wants to allow horrible people to run wild on Twitter.
The Verge has an interesting article from 2019 about Gab using Mastodon [2]. The fact that over the last 2.5 years I didn’t even hear of Gab using Mastodon suggests that the fears of some people significantly exceeded the problem. I’m sure that some Gab users managed to harass some Mastodon users, but generally they were apparently banned quickly. As an aside the Mastodon server I use doesn’t appear to ban Gab, a search for Gab on it gave me a user posting about being “pureblood” at the top of the list.
Gab claims to have 4 million accounts and has an estimated 100,000 active users. If 5.5% of Tesla owners became active users on a hypothetical Tesla server that would be the largest Mastodon server. Elon could demonstrate his commitment to free speech by refusing to ban Gab in any way. The Wikipedia page about Gab [3] has a long list of horrible people and activities associated with it. Is that the “free speech” to associate with Tesla? Polestar makes some nice electric cars that appear quite luxurious [4] and doesn’t get negative PR from the behaviour of it’s owner, that’s something Elon might want to consider.
Is this really about bragging rights? Buying a controlling interest in a company that has a partial monopoly on Internet communication is something to boast about. Could users of commercial social media be considered serfs who serve their billionaire overlord?
Windows 10 added a new “PIN” login method, which is an optional login method instead of an Internet based password through Microsoft or a Domain password through Active Directory. Here is a web page explaining some of the technology (don’t watch the YouTube video) [1]. There are three issues here, whether a PIN is any good in concept, whether the specifics of how it works are any good, and whether we can copy any useful ideas for Linux.
Is a PIN Any Good?
A PIN in concept is a shorter password. I think that less secure methods of screen unlocking (fingerprint, face unlock, and a PIN) can be reasonably used in less hostile environments. For example if you go to the bathroom or to get a drink in a relatively secure environment like a typical home or office you don’t need to enter a long password afterwards. Having a short password that works for short time periods of screen locking and a long password for longer times could be a viable option.
It could also be an option to allow short passwords when the device is in a certain area (determined by GPS or Wifi connection). Android devices have in the past had options to disable passwords when at home.
Is the Windows 10 PIN Any Good?
The Windows 10 PIN is based on TPM security which can provide real benefits, but this is more of a failure of Windows local passwords in not using the TPM than a benefit for the PIN. When you login to a Windows 10 system you will be given a choice of PIN or the configured password (local password or AD password).
As a general rule providing a user a choice of ways to login is bad for security as an attacker can use whichever option is least secure.
The configuration options for Windows 10 allow either group policy in AD or the registry to determine whether PIN login is allowed but doesn’t have any control over when the PIN can be used which seems like a major limitation to me.
The claim that the PIN is more secure than a password would only make sense if it was a viable option to disable the local password or AD domain password and only use the PIN. That’s unreasonably difficult for home users and usually impossible for people on machines with corporate management.
Ideas For Linux
I think it would be good to have separate options for short term and long term screen locks. This could be implemented by having a screen locking program use two different PAM configurations for unlocking after short term and long term lock periods.
Having local passwords based on the TPM might be useful. But if you have the root filesystem encrypted via the TPM using systemd-cryptoenroll it probably doesn’t gain you a lot. One benefit of the TPM is limiting the number of incorrect attempts at guessing the password in hardware, the default is allowing 32 wrong attempts and then one every 10 minutes. Trying to do that in software would allow 32 guesses and then a hardware reset which could average at something like 32 guesses per minute instead of 32 guesses per 320 minutes. Maybe something like fail2ban could help with this (a similar algorithm but for password authentication guesses instead of network access).
Having a local login method to use when there is no Internet access and network authentication can’t work could be useful. But if the local login method is easier then an attacker could disrupt Internet access to force a less secure login method.
Is there a good federated authentication system for Linux? Something to provide comparable functionality to AD but with distributed operation as a possibility?
I’ve currently got Covid, I believe I caught it on the 11th of April (my first flight since the pandemic started) with a runny nose on the 13th and a positive RAT on the evening of the 14th. I got an official PCR test on the 16th with a positive result returned on the 17th. I think I didn’t infect anyone else (yay)! Now I seem mostly OK but still have a lack of energy, sometimes I suddenly feel tired after 20 minutes of computer work.
The progression of the disease was very different to previous cold/flu diseases that I have had. What I expect is to start with a cough or runny nose, escalate with more of that, have a day or two of utter misery with congestion, joint pain, headache, etc, then have it suddenly decrease overnight. For Covid I had a runny nose for a couple of days which went away then I got congestion in my throat with serious coughing such that I became unable to speak. Then the coughing went away and I had a really bad headache for a day with almost no other symptoms. Then the headache went away and I was coughing a bit the next day. The symptoms seemed to be moving around my body.
I got a new job and they wanted me to fly to the head office to meet the team, I apparently got it on the plane a day before starting work. I’ve discussed this with a manager and stated my plan to drive instead of fly in future. It’s only a 7 hour drive and it’s not worth risking the disease to save 3-4 hours travel time, or even the 5 hours travel I’d have saved if the airports were working normally (apparently a lot of airport staff are off sick so there’s delays). Given the flight delays and the fact that I was advised to arrive extra early at the airport I ended up taking almost 7 hours for the entire trip!
7 hours driving is a bit of effort, but sitting in an airport waiting for a delayed flight while surrounded by diseased people isn’t fun either.
In response to my post about Android phones without Google Play [1] I received an email recommending Joplin for notes on Android [2].
Joplin supports storing notes on a number of protocols including Nextcloud and WebDAV. I setup WebDAV because it’s easiest, here is Digital Ocean instructions for WebDAV on Apache [3]. That basically works. One problem for my use case is that the Joplin client doesn’t support accounts on multiple servers and the only released way of sharing notes between accounts is using the paid Joplin Cloud service.
There is a Joplin Server in beta which allows sharing notes but that is designed to run in Docker and is written in TypeScript so it was too much pain to setup. One mitigating factor is that there are “Notebooks” which are collections of notes. So if multiple people who trust each other share an account they can have Notebooks for personal notes and a Notebook for shared notes.
There is also a Snap install of the client for Debian [4]. Snap isn’t my favourite way of doing things but packaging JavaScript programs will probably be painful so I’ll do it if I continue using Joplin.
A while ago I was given a few reasonably high-end Android phones to give away. I gave two very nice phones to someone who looks after refugees so a couple of refugee families could make video calls to relatives. The third phone is a Huawei Nova 7i [1] which doesn’t have the Google Play Store. The Nova 7i is a ridiculously powerful computer (8G of RAM in a phone!!!) but without the Google Play Store it’s not much use to the average phone user. It has the “HuaWei App Gallery” which isn’t as bad as most of the proprietary app stores of small players in the Android world, it has SnapChat, TikTok, Telegram, Alibaba, WeChat, and Grays auction (an app I didn’t even know existed) along with many others. It also links to ApkPure (apparently a 3rd party app installer that “obtains” APK files for major commercial apps) for Facebook among others. The ApkPure thing might be Huawei outsourcing the violation of Facebook terms of service. For the moment I’ve decided to only use free software on this phone and use my old phone for non-free stuff (Facebook, LinkedIn, etc). The eventual aim is that I can only carry a phone with free software for normal use and carry a second phone if I’m active on LinkedIn or something. My recollection is that when I first got the phone (almost 2 years ago) it didn’t have such a range of apps.
The first thing to install was f-droid [2] as the app repository. F-droid has a repository of thousands of free software Android apps as well as some apps that are slightly less free which are tagged appropriately. You can install the F-Droid app from the web site. As an aside I had to go to settings and enable “force old index format” to get the list of packages, I don’t know why as other phones had worked without it.
Here are the F-Droid apps I installed:
- Kdeconnect to transfer files to PC. This has some neat features including using the PC keyboard on Android. One downside is that there’s no convenient way to kill it. I don’t want it hanging around, I want to transfer a file and close it down to minimise exposure.
- K9 is an Android app for email that I’ve used for over a decade now. Previously I’ve used it from the Play Store but it’s available in F-droid. I used Kdeconnect to transfer the exported configuration from my old phone to my PC and then from my PC to my new phone.
- I’m now using SchildiChat for Matrix as a replacement for Google Hangouts (I previously wrote about how Google is killing Hangouts [3]). One advantage of SchildiChat is that it keeps a notification running 24*7 to reduce the incidence of Android killing it. The process of sending private messages with Matrix seems noticeably slower than Hangouts, while Google will inevitably be faster than a federated system (if only because they buy better hardware than I rent) the difference shouldn’t be enough to notice (my Matrix servers might need some work).
- I used ffupdater to install Firefox. It can also install other browsers that don’t publish APK files. One of the options is “Ungoogled Chromium” which I’m not going to use even though I’ve found Google Chrome to be a great browser, I think I should go all the way in avoiding Google. There’s no description in the app of the differences between the browsers, the ffupdater web page has information about the browsers [4].
- I use Tusky for Mastodon which is a replacement for Twitter. My Mastodon address is @etbe@mastodon.nzoss.nz. Currently Mastodon needs more users, there are plenty of free servers out there and the New Zealand Open Source Society is just one I have contact with.
- I have used ConnectBot for ssh connections from Android for over 10 years, previously via the Play Store but it’s also in F-droid. To get the hash of a key from a server in the way ConnectBot displays it run “ssh-keygen -l -E md5 -f /etc/ssh/ssh_host_ed25519_key.pub“.
- I initially changed Keyboard from MS Swiftkey to the Celia keyboard that came with the phone. But it’s spelling correction was terrible, almost never suggesting words with apostrophes when appropriate and also having no apparent option to disable adult words. I’m now using OpenBoard which is a port of the Google Android keyboard which works well.
- I’ve just installed “primitive ftpd” for file transfer, it supports ftp and sftp protocols and is well written.
- I’ve installed the mpv video player which plays FullHD video at high quality using hardware decoding. I don’t need to do that sort of thing (the screen is too small to make it worth FullHD video), but it’s nice to have.
- For barcodes and QR codes I’m using Binary Eye which seems better than the Play Store one I had used previously.
- For playing music I’ve tried using the Simple Music Player (which is nice for mp3s), but it doesn’t play m4a or webm files. Auxio and Music Player Go play mp3 and m4a but not webm. So far the only programs I’ve found that can play webm are VLC and MPV, so I’m trying out VLC as a music player which it basically does but a program with the same audio features and no menu options about video would be better. Webm is important to me because I have some music videos downloaded from YouTube and webm allows me to put a binary copy of the audio data into an audio file.
Future Plans
The current main things I’m missing are a calendar, a contact list, and a shared note taking system (like Google Keep). For calendaring and a contact list the CalDAV and CardDAV protocols seem best. The most common implementation on the server side appears to be DAViCal [5]. The Nextcloud system supports CalDAV, CardDAV, web editing of notes and documents (including LibreOffice if you install that plugin) [6]. But it is huge and demands write access to all it’s own code (bad for security), and it’s not packaged for Debian. Also in my tests it gave me an error 401 when I tried to authenticate to it from the Android Nextcloud client. I’ve seen a positive review about Radicale, a simple CalDAV and CardDAV server that doesn’t need a database [7]. I prefer the Unix philosophy of keeping things simple with file storage unless there’s a real need for anything else. I don’t think that anything I ever do with calendaring will require the PostgreSQL database that DAViCal uses.
I’ll give Radicale a go for CalDAV and CardDAV, but I still need something for shared notes (shopping lists etc). Suggestions welcome.
Current Status
Lack of a contacts list is a major loss of functionality in a phone. I could store contacts in the phone memory or on the SIM, but I would still have to get all my old contacts in there and also getting something half working reduces motivation for getting it working properly. Lack of a calendar is also a problem, again I could work around that by exporting all my Google calendars as iCal URLs but I’d rather get it working correctly.
The lack of shared notes may be a harder problem to solve given the failure of Nextcloud. For that I would consider just having the keep.google.com web site always open in Mozilla at least in the short term.
At the moment I require two phones, my new Android phone without Google and the old one for my contacts list etc. Hopefully in a week or so I’ll have my new phone doing contacts, calendaring, and notes. Then my old phone will just be for proprietary apps which I don’t need most of the time and I can leave it at home when I don’t need that sort of thing.
When I got my HP ML110 Gen9 working as a workstation I initially was under the impression that boot wasn’t supported on NVMe and booted it from USB. I found USB booting with legacy boot to be unreliable so decided to try EFI booting and noticed that the NVMe devices were boot candidates with UEFI. Making one of them bootable was more complex than expected because no-one seems to have documented such things. So here’s my documentation, it’s not great but this method has worked once for me.
Before starting major partitioning work it’s best to run “parted -l and save the output to a file, that can allow you to recreate partitions if you corrupt them. One thing I’m doing on systems I manage is putting “@reboot /usr/sbin/parted -l > /root/parted.log” in the root crontab, then when the system is backed up the backup server gets any recent changes to partitioning (I don’t backup /var/log on all my systems).
Firstly run parted on the device to create the EFI and /boot partitions, note that if you want to copy and paste from this you must do so one line at a time, a block paste seemed to confuse parted.
mklabel gpt
mkpart EFI fat32 1 99
mkpart boot ext3 99 300
toggle 1 boot
toggle 1 esp
p
# Model: CT1000P1SSD8 (nvme)
# Disk /dev/nvme1n1: 1000GB
# Sector size (logical/physical): 512B/512B
# Partition Table: gpt
# Disk Flags:
#
# Number Start End Size File system Name Flags
# 1 1049kB 98.6MB 97.5MB fat32 EFI boot, esp
# 2 98.6MB 300MB 201MB ext3 boot
q
Here are the commands needed to create the filesystems and install the necessary files. This is almost to the stage of being scriptable. Some minor changes need to be made to convert from NVMe device names to SATA/SAS but nothing serious.
mkfs.vfat /dev/nvme1n1p1
mkfs.ext3 -N 1000 /dev/nvme1n1p2
file -s /dev/nvme1n1p2 | sed -e s/^.*UUID/UUID/ -e "s/ .*$/ \/boot ext3 noatime 0 1/" >> /etc/fstab
file -s /dev/nvme1n1p1 | tr "[a-f]" "[A-F]" |sed -e s/^.*numBEr.0x/UUID=/ -e "s/, .*$/ \/boot\/efi vfat umask=0077 0 1/" >> /etc/fstab
# edit /etc/fstab to put a hyphen between the 2 groups of 4 chars for the VFAT filesystem UUID
mount /boot
mkdir -p /boot/efi /boot/grub
mount /boot/efi
mkdir -p /boot/efi/EFI/debian
apt install efibootmgr shim-unsigned grub-efi-amd64
cp /usr/lib/shim/* /usr/lib/grub/x86_64-efi/monolithic/grubx64.efi /boot/efi/EFI/debian
file -s /dev/nvme1n1p2 | sed -e "s/^.*UUID=/search.fs_uuid /" -e "s/ .needs.*$/ root hd0,gpt2/" > /boot/efi/EFI/debian/grub.cfg
echo "set prefix=(\$root)'/boot/grub'" >> /boot/efi/EFI/debian/grub.cfg
echo "configfile \$prefix/grub.cfg" >> /boot/efi/EFI/debian/grub.cfg
grub-install
update-grub
If someone would like to make a script that can handle the different partition names of regular SCSI/SATA disks, NVMe, CCISS, etc then that would be great. It would be good to have a script in Debian that creates the partitions and sets up the EFI files.
If you want to have a second bootable device then the following commands will copy a GPT partition table and give it new UUIDs, make very certain that $DISKB is the one you want to be wiped and refer to my previous mention of “parted -l“. Also note that parted has a rescue command which works very well.
sgdisk /dev/$DISKA -R /dev/$DISKB
sgdisk -G /dev/$DISKB
To backup a GPT partition table run a command like this. Note that if sgdisk is told to backup a MBR partitioned disk it will say “Found invalid GPT and valid MBR; converting MBR to GPT forma” which is probably a viable way of converting MBR format to GPT.
sgdisk -b sda.bak /dev/sda
|
|
