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All posts for the month October, 2018

The Raspberry Pi is a wonderful platform, not only because it’s well supported, but that’s as a result of it’s price and flexibility. Lots of USB ports on the 2 and 3 models, HDMI, Ethernet, and now it also includes wireless and Bluetooth onboard.

I have been meaning to experiment a build a wireless repeater using a Pi, and finally got a chance (and the courage) to attempt this feat. It wasn’t easy, and this is by no means a comprehensive guide, but rest assured that if you get it to work, you’ll understand why.

I started with a Pi 3, 16GB Kingston micro SD card, and an external Atheros AR9271 based adapter from TP-Link and made for a TCL television. I got this from an infamous friend, @d4rkm4tter of the #WifiCactus and it’s “high-gain” antenna gives it extra reach for connecting to distant APs.

Raspbian Stretch was used, the full version because I’m not a full cli master, starting with the April 2018 image, then eventually using the October 2018 installer (which is nicer).

My intention is to use the external USB adapter to associate with a remote AP and get a connection. This would be bridged by the Pi and dnsmasq with the built-in wireless adapter on the Pi. My testing shows that the 802.11n Atheros adapter with the external antenna does indeed have improved gain.

I followed the guide found here: <a href=”https://pimylifeup.com/raspberry-pi-wifi-extender/”>PiMyLifeUp</a>

All of this was very helpful, and the guide is extremely well written and intended for the Pi2/3 owners. My only change to this guide, or difficulty with, was that I wanted to invert the adapter role, so changing “wlan0” to “wlan1” and vice-versa throughout was necessary.

The packages called dnsmasq and hostpad are the real workers here, and to the heavy lifting, routing, and interfacing with the adapters. I had some success with just following this setup, but also found that it didn’t _just work_ so the tinkering and frustration curve began.

One neat trick that I did learn from elsewhere is that hostpad can be run with a config file as an argument, which means that you’ll start the service with a verbose console feed, but it will let you know if the config file is working and whether the AP has started. When you see “AP-ENABLED” and few, if any errors, you’ll finally know you’re there.

As of this writing, I’ve been running the AP for several days. Performance is weak for throughput, at less than 10Mbps, but the application this is meant for, or would be used in, is a location that has very poor cellular coverage for non-Verizon customers. This application of the Pi can be configured in a place or situation where _some_ connection is an improvement over _none_.

Interestingly, the PW-4210D adapter does have a removable antenna, so the use of a parabolic, omnidirectional, or yagi antenna with an adapter is possible for a very long run. There are also more solid, cheaper wireless bridges available online, but if you’re a tinkerer like I am, and have the spare hardware, there’s something special in feeling like you’ve made a bucket of parts do something interesting.

Go, do it.

Password managers like LastPass, Dashlane, Keepass, and 1Password (among others) are increasingly popular. Browsers, however, have been able to hold and store passwords for quite a long time.

Most of us use Firefox Sync or Chrome’s Google sign-in to keep things closer than a password manager is, with an eye towards simplicity rather than outright security. Sure, browsers have password requirements to use their vaults, but…

On a new PC, in Firefox, I’m struggling to get the browser to ask to save passwords. This is weird, as I’ve always seen the prompt when I enter a new password for a site, or update one. Not this time. In an effort to try again, perhaps thinking that a stored login was causing the issue, I clocked Remove All, and told Firefox to go ahead and remove all of the passwords.

Bear in mind that I’d put in text to filter this list down to two, a login item with and without “www” in the URL. So, it was showing a list of two items. Remove all would remove these two, right? Nope.

I got annoyed when Firefox stopped responding, and eventually got the message that a script was taking longer to run than expected, etc. I didn’t think more of this until I tried again to get Firefox to remember the site, and after it didn’t suggest saving the password, I checked the Saved Logins again only to find a completely empty list.

Oops. Breathe.

New PC is less than a month old. Old PC is right there. Sync loves to be tidy, so make sure it’s not connected to a network because, sure as anything, it’s going to remove them from that PC too if it can.

Open Firefox on the in-tact PC, enter “about:support” and look for the Profile Folder entry and click the Open Folder button. Search for “logins.json”, “key3.db” and “key4.db”.

I copied these to a USB stick, put that in the new PC, immediately put a backup elsewhere in the cloud, then closed Firefox on the new PC after opening that same profile folder on thew new PC. After copying all three files to the folder on the new PC, I held my breath, started Firefox, checked in Options for Saved Logins and saw a full list again.

Whew.

Now to get LastPass installed and export these to somewhere else more secure and cull the list of heavily-outdated passwords.

Oh, and yeah, figure out why Firefox isn’t asking to update or save new passwords…

I’ve had the unusual opportunity to get several used, late 2000s HP printers for use at work. Normally we get these new, fresh out of the box, and they’re maintained from that point. This has led to some interesting issues with firmware updates.

Anyone familiar with updates to firmware on HP printers made in the last decade knows that there are several ways to do these. The first is to install the printer locally on a Windows computer and run the updater program against this installed device. This works, and works well, but only if the firmware on the device supports it. Second is to use a built-in updater located on the printer’s web server, which is a feature on the higher-end Enterprise devices. Third is via FTP. Yeah, FTP.

After installing the printer as a local device, I have seen situations where the installer program will not work with a network printer object, whether it’s WSD or a TCP mapping. Usually this is resolved by plugging a device directly in to the printer, installing the local version, then running the program.

When this doesn’t work, however, FTP is still an option. It’s simple, and easy, but also a bit scary because this port is open by default, has no username or password, and allows a binary transfer directly to the devices. Even after a firmware update to a version less than 18 months old, this port remains open.

This works, and gets around the frustrating update process that most end users would use, but hey, at least isn’t not TFTP.