David Gessel
Signal Desktop: Probably a good thing
Signal is an easy to use chat tool that competes (effectively) with What’sApp or Viber. They’ve just released a desktop version which is being “preview released/buzz generating released.” It is developed by a guy with some cred in the open source and crypto movement, Moxie Marlinspike. I use it, but do not entirely trust it.
I’m not completely on board with Signal. It is open source, and so in theory we can verify the code. But there’s some history I find disquieting. So while I recommend it as the best, easiest to use, (probably) most secure messaging tool available, I do so with some reservations.
- It originally handled encrypted SMS messages. There is a long argument about why they broke SMS support on the mailing lists. I find all of the arguments Whisper Systems made specious and unconvincing and cannot ignore the fact that the SMS tool sent messages through the local carrier (Asiacell, Korek, or Zain here). Breaking that meant secure messages only go through Whisper Systems’ Google-managed servers where all metadata is captured and accessible to the USG. Since it was open source, that version has been forked and is still developed, I use the SMSSecure fork myself
- Signal has captured all the USG funding for messaging systems. Alternatives are not getting funds. This may make sense from a purely managerial point of view, but also creates a single point of infiltration. It is far easier to compromise a single project if there aren’t competing projects. Part of the strength of Open Source is only achieved when competing development teams are trying to one up each other and expose each other’s flaws (FreeBSD and OpenBSD for example). In a monoculture, the checks and balances are weaker.
- Signal has grown more intimate with Google over time. The desktop version sign up uses your “google ID” to get you in the queue. Google is the largest commercial spy agency in the world, collecting more data on more people than any other organization except probably the NSA. They’re currently an advertising company and make their money selling your data to advertisers, something they’re quite disingenuous about, but the data trove they’ve built is regularly mined by organizations with more nefarious aims than merely fleecing you.
What to do? Well, I use signal. I’m pretty confident the encryption is good, or at least as good as anything else available. I know my metadata is being collected and shared, but until Jake convinces Moxie to use anonymous identifiers for accounts and message through Tor hidden nodes, you have to be very tech savvy to get around that and there’s no Civil Society grants going to any other messaging services using, for example, an open standard like a Jabber server on a hidden node with OTR.
For now, take a half step up the security ladder and stop using commercial faux security (or unverifiable security, which is the same thing) and give Signal a try.
Maybe at some later date I’ll write up an easy to follow guide on setting up your own jabber server as a tor hidden service and federating it so you can message securely, anonymously, and keep your data (meta and otherwise) on your own hardware in your own house, where it still has at least a little legal protection.
Successful connect to WPA2 with Linux Mint 17
I found myself having odd problems connecting to WPA2 encrypted wireless networks with a new laptop. There must be more elegant solutions to this problem, but this worked for me. The problem was that I couldn’t connect to a nearby hotspot secured with WPA2 whether I used the default config tool for mint, Wicd Network Manager, or the command line. Errors were either “bad password” or the more detailed errors below.
As with any system variation mileage may vary, my errors look like:
wlan0: CTRL-EVENT-SCAN-STARTED wlan0: SME: Trying to authenticate with 68:72:51:00:26:26 (SSID='WA-bullet' freq=2462 MHz) wlan0: Trying to associate with 68:72:51:00:26:26 (SSID='WA-bullet' freq=2462 MHz) wlan0: Associated with 68:72:51:00:26:26 wlan0: CTRL-EVENT-DISCONNECTED bssid=68:72:51:00:26:26 reason=3 locally_generated=1
and my system config is reported as:
# lspci -vv |grep -i wireless 3e:00.0 Network controller: Intel Corporation Wireless 7260 (rev 6b) Subsystem: Intel Corporation Dual Band Wireless-AC 7260 # uname -a Linux dgzb 3.16.0-38-generic #52~14.04.1-Ubuntu SMP Fri May 8 09:43:57 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux
I found useful commands for manually setting up a wpa_supplicant.conf file here, and for disabling 802.11n here. The combination was needed to get things working.
The following successfully connects to a WPA2-secured network:
$ sudo su $ iw dev ... Interface [interfacename] (typically wlan0, assumed below) $ iw wlan0 scan ... SSID: [ssid] ... RSN: (if present means the network is secured with WPA2) $ wpa_passphrase [ssid] >> /etc/wpa_supplicant.conf ...type in the passphrase for network [ssid] and hit enter... $ sh -c 'modprobe -r iwlwifi && modprobe iwlwifi 11n_disable=1' $ wpa_supplicant -i wlan0 -c /etc/wpa_supplicant.conf
(should show CTRL-EVENT-CONNECTED)
(open a new terminal leaving the connection open, ending the command disconnects)
$ sudo su $ dhclient wlan0
(should be connected now)
That’s so Colorado
“…Not allowed in the cargo hold: lithium batteries, e-cigarettes, personal vapes.”
United’s Magic Trays
@United has new coach trays that are coated with a material that has an amazing coefficient of friction. They are not sticky at all—there’s no adhesion effect—it is all friction. Even low surface energy plastics don’t slide on it at all.
The approximately 75-80° angle in the picture is the point at which the cup topples over itself. It isn’t adhered to the surface and it doesn’t appear to slide at all before toppling.
This would be the perfect coating for a smart phone pad in a car. I never managed to find out who made it.
Disk Checks for Large Arrays
If you have a large array of disks attached to your server, which is obviously going to be running FreeBSD or OpenBSD if you care about security, stability, and scalability; there are some tricks for dealing with large numbers of disks (like having 227 4TB disks attached to a single host).
Using Bash (yes there are security issues, but it is powerful)
# for i in `seq 0 227`; do smartctl -t short /dev/da$i; sleep 15; done 1Thanks Jared
executes a short smart test on all disks. Smartctl seems to max out at 32 concurrent tests, so sleep 15 ensures the 3 minute tests are finishing before new ones are executed. If you’re in a hurry, sleep 5 should do the trick and ensure all of them execute.
to get results try something like:
# for i in `seq 0 227`; do echo "/dev/da$i"; smartctl -a /dev/da$i; sleep .5; done
Bulk Fixes
Problem with the disks – need to clear existing formatting?
unmount each disk
# for i in `seq 0 227`; do umount -f /dev/da$i; done
unlock (if needed)
# sysctl kern.geom.debugflags=0x10
Overwrite the start of each disk
# for i in `seq 0 227`; do dd if=/dev/zero of=/dev/da$i bs=1k count=100; done
Overwrite the end of each disk
# for i in `seq 0 227`; do dd if=/dev/zero of=/dev/da$i bs=1m oseek=`diskinfo da$i | awk '{print int($3 / (1024*1024)) - 4;}'`; done
Recreate GPT (for ZFS)
# for i in `seq 0 227`; do gpart create -s gpt /dev/da$i; sleep .5; done
Destroy multipaths
# for i in `seq 1 114`; do gmultipath destroy disk$i; done
Disable multipath completely
# for i in `seq 1 114`; do gmultipath destroy disk$i; done
# gmultipath unload
# mv /boot/kernel-debug/geom_multipath.ko /boot/kernel-debug/geom_multipath.ko.bad
# mv /boot/kernel/geom_multipath.ko /boot/kernel/geom_multipath.ko.bad
Footnotes
| ↑1 | Thanks Jared |
|---|
