Turning off seccomp sandbox in vsftpd

Within the last week, I set up virtual web server using Arch Linux to satisfy my own curiosity since the DIY nature of Arch means that you can build up exactly what you need without having any real constraints put upon you. What didn’t surprise me about this was that it took me more work than the virtual server that I created using Ubuntu Server but I didn’t expect ProFTPD to be missing from the main repositories. The package can be found in the AUR but I didn’t fancy the prospect of dragging more work on myself so I went with vsftpd (Very Secure FTP Daemon) instead. In contrast to ProFTPD, this is available in the standard repositories and there is a guide to its use in the Arch user documentation.

However, while vsftpd worked well just after installation, connections to the virtual FTP soon failed with FileZilla  began issuing uninformative messages. In fact, it was the standard command line FTP client on my Ubuntu machine that was more revealing. It issued the following message that let me to the cause after my engaging the services of Google:

500 OOPS: priv_sock_get_cmd

With version 3.0 of vsftpd, a new feature was introduced and it appears that this has caused problems for a few people. That feature is seccomp sandboxing and it can turned off by adding the following line in /etc/vsftpd.conf:


That solved my problem and version 3.0.2 of vsftpd should address the issue with seccomp sandboxing anyway. In case, this solution isn’t as robust as it should be because seccomp isn’t supported in the Linux kernel that you are using, turning off the new feature still needs to be an option though.

Piggybacking an Android Wi-Fi device off your Windows PC’s internet connection

One of the disadvantages of my Google/Asus Nexus 7 is that it needs a Wi-Fi connection to use. Most of the time this is not a problem since I also have a Huawei mobile WiFi hub from T-Mobile and this seems to work just about anywhere in the U.K. Away from the U.K. though, it won’t work because roaming is not switched on for it and that may be no bad thing with the fees that could introduce. My HTC Desire S could deputise but I need to watch costs with that too.

There’s also the factor of download caps and those apply both to the Huawei and to the HTC. Recently, I added Anquet‘s Outdoor Map Navigator (OMN) to my Nexus 7 through the Google Play store for a fee of £7 and that allows access to any walking maps that I have bought from Anquet. However, those are large downloads so the caps start to come into play. Frugality would help but I began to look at other possibilities that make use of a laptop’s Wi-Fi functionality.

Looking on the web, I found two options for this that work on Windows 7 (8 should be OK too): Connectify Hotspot and Virtual Router Manager. The first of these is commercial software but there is a Lite edition for those wanting to try it out; that it is not a time limited demo is not something that I can confirm though that did not seem to be the case since it looked as if only features were missing from it that you’d get if you paid for the Pro variant. The second option is an open source one and is free of charge apart from an invitation to donate to the project.

Though online tutorials show the usage of either of these to be straightforward, my experiences were not all that positive at the outset. In fact, there was something that I needed to do and that is why this post has come to exist at all. That happened even after the restart that Conectify Hotspot needed as part of its installation; it runs as a system service so that’s why the restart was needed. In fact, it was Virtual Router Manager that told me what the issue was and it needed no reboot. Neither did it cause network disconnection of a laptop like the Connectify offering did on me and that was the cause of its ejection from that system; limitations in favour of its paid addition aside, it may have the snazzier interface but I’ll take effective simplicity any day.

Using Virtual Router Manager turns out to be simple enough. It needs a network name (also known as an SSID), a password to restrict who accesses the network and the internet connection to be shared. In my case, the was Local Area Connection on the drop down list. With all the required information entered,  I was ready to start the router using the Start Network Router button. The text on this changes to Stop Network Router when the hub is operational or at least it should have done for me on the first time that I ran it. What I got instead was the following message:

The group or resource is not in the correct state to perform the requested operation.

The above may not say all that much but it becomes more than ample information if you enter it into the likes of Google. Behind the scenes, Virtual Router Manager is using native Windows functionality is create a WiFi hub from a PC and it appears to be the Microsoft Virtual Wi-Fi Miniport Adapter from what I have seen. When I tried setting up an adhoc Wi-Fi network from a laptop to the Nexus 7 using Windows’ own network set up capability via its Control Panel, it didn’t do what I needed so there might be something that third party software can do. So, the interesting thing about the solution to my Virtual Router Manager problem was that it needed me to delve into the innards of Windows a little.

Firstly, there’s running Command Prompt (All Programs > Accessories) from the Start Menu with Administrator privileges. It helps here if the account with which you log into Windows is in the Administrators group since all you have  to do then is right click on the Start Menu entry and choose Run as administrator entry in the pop-up context menu. With a command line window now open, you then need to issue the following command:

netsh wlan set hostednetwork mode=allow ssid=[network name] key=[password] keyUsage=persistent

When that had done its thing, Virtual Router Manager worked without a hitch though it did turn itself after a while and that may be no bad thing from the security standpoint. On the Android side, it was a matter of going in Settings > Wi-Fi and choose the new network that have been creating on the laptop. This sort of thing may apply to other types of tablet (Dare I mention iPads?) so you could connect anything to the hub without needing to do any more on the Windows side.

For those wanting to know what’s going on behind the scenes on Windows, there’s a useful tutorial on Instructables that shows what third party software is saving you from having to do. Even if I never go down the more DIY route, I probably have saved myself having to buy a mobile Wi-Fi hub for any trips to Éire. For now, the Irish 3G dongle that I already have should be enough.

A new phone

After a few years with a straightforward Nokia 1661 and a PAYG Blackberry 8520, I decided to go and upgrade from the former to an HTC Wildfire S. So far, the new phone has been good to me with only a few drawbacks. Other than working out how to insert a SIM card, the phone has been easy to use with just a few nuances to learn, such as finger pinch zooming and dealing with an onscreen keyboard as opposed to a real one.

The touchscreen interface and the 3G capability are the big changes from my Blackberry and both make web browsing so much faster too, especially with the larger screen. For instance, checking RSS feeds with Google Reader and emails is so much faster on the move with the screen being very responsive most of the time that I am using it; it does get dirty like others so either a screen cover or frequent cleaning with a camera lens cloth would be no bad thing. The onscreen keyboard remains something to which I need to grow accustomed and probably is the one area where the Blackberry continues to hold sway though turning the phone sideways and tapping it on the side to change orientation helps a lot. That makes the keys larger and, while my finger are not the thickest, there are fewer cases of hitting the wrong key. Even then, you need to get used to switching between alphabet and numeric keyboards and that applies also when you need punctuation marks like commas and so on.

Otherwise, the user interface is bright and pleasing to the eye with the typical presentation of both a clock and current weather on there. Handily, the screen is locked easily too with a press of the button at the top right of the phone. That will put a stop to inadvertent phone calls, emailing, web browsing and other things so it is to be commended. To unlock the screen, all that’s needed is to swipe the lock bar to the bottom. Any alerts are viewed in a similar way with holding down your finger on the top bar presenting an extension that can be pulled all of the way down to see what’s there.

With an icon for the Android Marketplace on the main screen, I got to adding a few apps and you can set these to update automatically too but you need to watch your phone contract’s data allowance. The one for WordPress works better than it does on my Blackberry but it seems that retweeting with UberSocial is much less good on the Android platform. For one thing, feeds for all accounts are presented on the one screen and swiping left to right is needed for replying, retweeting and other operations and that’s not working out so smoothly for me yet. Maybe I’ll try an alternative. There are others that I have downloaded too and these include one from CrossCountry Trains and that seems to be a nice offering even if it failed to find trains between Macclesfield and Edale of a Sunday morning. For those omissions, I have an alternative in place and I also have the LinkedIn app too. That seems to work well too. Usefully, it is possible to move these to the phones microSD card to avoid filling up the limited space that’s on offer. However, that isn’t to say that I will be going mad on these things.

Of course, any phone should be good at making and taking phones and the Wildfire seems to be doing well on this score too. Firstly, contacts were read from the SIM but they can be transferred from an old phone using Bluetooth connections too. Sound is good and loud though you need to be on a call to adjust the speaker volume with the rocker button on the side of the phone. Otherwise, that just changes the volume of the ring tone. Without any adjustments, the phone seems to vibrate and ring at the same time though that may be something that I get to changing in time. The pings emitted when new text messages, emails or tweets fall into the same category.

If there’s any downside to this phone, it has to be battery life. Unlike others that I have had, this is a phone that needs charging every night at the very least. Maybe that’s the price of having a nice bright responsive screen but it would be no harm if it lasted longer. Others have found the same thing and reported as much on the web though some have having worse experiences than others. There are some hints regarding how to conserve battery life but they include such things as switching off 3G or data capabilities and neither appeal to me; after all, I might as well use my old Nokia if this is all that can be offered. Instead, I am wondering if acquiring a spare battery might be no bad idea because that’s what I do for my Pentax DSLR (note in passing: I haven’t got to using the phone’s own camera but recent wintry weather had me tempted by the idea, especially with the likes of Twitpic and YFrog out there.). Taking things further, others have mentioned getting a larger capacity replacement but that sounds more risky.

All in all, first impressions of the HTC Wildfire are good ones. Over time, I should find out more about the ins and outs of the gadget. After all, it is a mini-computer with its own operating system and other software. Since I continue to learn more and more about PC’s everyday, the same should be the case here too.

A waiting game

Having been away every weekend in July, I was looking forward to a quiet one at home to start August. However, there was a problem with one of my websites hosted by Fasthosts that was set to occupy me for the weekend and a few weekday evenings afterwards.

The issue appeared to be slow site response so I followed advice given to me by second line support when this website displayed the same type of behaviour: upgrade from Apache 1.3 to 2.2 using the control panel. Unfortunately for me, that didn’t work smoothly at all and there seemed to be serious file loss as a result. Raising a ticket with the support desk only got me the answer that I had to wait for completion and I now have come to the conclusion that the migration process may have got stuck somewhere along the way. Maybe another ticket is in order.

There were a number of causes of the waiting that gave rise to the title of this post. Firstly, support for low costing isn’t exactly timely and I do wonder if it’s any better for more prominent websites. Restoration of websites by FTP is another activity that takes up plenty of time as does rebuilding databases and populating them with data. Lastly, there’s changing the DNS details for a website. In hindsight, there may be ways of reducing the time demands of these. For instance, contacting a support team by telephone may be quicker unless there is a massive queue awaiting attention and there was a wait of several hours one night when a security changeover affected a multitude of Fasthosts users. Of course, it is not a panacea at the best of times as we have known since all those stories began to do the rounds in the middle of the 1990’s. Doing regular backups would help the second though the ones that I was using for the restoration weren’t too bad at all. Nevertheless, they weren’t complete so there was unfinished business that required resolution later. The last of these is helped along by more regular PC restarts so that unexpected discovery will remain a lesson for the future though I don’t plan on moving websites around for a while. After all, getting DNS details propagated more quickly really is a big help.

While awaiting a response from Fasthosts, I began to ponder the idea of using an alternative provider. Perusal of the latest digital edition of .Net (I now subscribe to the non-paper edition so as to cut down on the clutter caused by having paper copies about the place) ensued before I decided to investigate the option of using Webfusion. Having decided to stick with shared hosting, I gave their Unlimited Linux option a go. For someone accustomed to monthly billing, it was unusual to see annual biannual and triannual payment schemes too. The first of these appears to be the default option so a little care and attention is needed if you want something else. In order to encourage you to stay with Webfusion longer, the per month is on sliding scale: the longer the period you buy, the lower the cost of a month’s hosting.

Once the account was set up, I added a database and set to the long process of uploading files from my local development site using FileZilla. Having got a MySQL backup from the Fasthosts site, I used the provided PHPMyAdmin interface to upload the data in pieces not exceeding the 8 MB file size limitation. It isn’t possible to connect remotely to the MySQL server using the likes of MySQL Administrator so I bear with this not so smooth process. SSH is another connection option that isn’t available but I never use it much on Fasthosts sites anyway. There were some questions to the support people along and the first of these got a timely answer though later ones took longer before I got an answer. Still, getting advice on the address of the test website was a big help while I was sorting out the DNS changeover.

Speaking of the latter, it took a little doing and not little poking around Webfusion’s FAQ’s before I made it happen. First, I tried using name servers that I found listed in one of the articles but this didn’t seem to achieve the end that I needed. Mind you, I would have seen the effects of this change a little earlier if I had rebooted my PC earlier than I did than I did but it didn’t occur to me at the time. In the end, I switched to using my domain provider’s name servers and added the required information to them to get things going. It was then that my website was back online in some fashion so I could any outstanding loose ends.

With the site essentially operating again, it was time to iron out the rough edges. The biggest of these was that MOD_REWRITE doesn’t seem to work the same on the Webfusion server like it does on the Fasthosts ones. This meant that I needed to use the SCRIPT_URI CGI variable instead of PATH_INFO in order to keep using clean URL’s for a PHP-powered photo gallery that I have. It took me a while to figure that out and I felt much better when I managed to get the results that I needed. However, I also took the chance to tidy up site addresses with redirections in my .htaccess file in an attempt to ensure that I lost no regular readers, something that I seem to have achieved with some success because one such visitor later commented on a new entry in the outdoors blog.

Once any remaining missing images were instated or references to them removed, it was then time to do a full backup for sake of safety. The first of these activities was yet another consumer while the second didn’t take so long and I need to do this more often in case anything happens. Hopefully though, the relocated site’s performance continues to be as solid as it is now.

The question as to what to do with the Fasthosts webspace remains outstanding. Currently, they are offering free upgrades to existing hosting packages so long as you commit for a year. After my recent experience, I cannot say that I’m so sure about doing that kind of thing. In fact, the observation leaves me wondering if instating that very extension was the cause of breaking my site. In fact, it appears that the migration from Apache 1.3 to 2.2 seems to have got stuck for whatever reason. Maybe another ticket should be raised but I am not decided on that yet. All in all, what happened to that Fasthosts website wasn’t the greatest of experiences but the service offered by Webfusion is rock solid thus far. While wondering if the service from Fasthosts wasn’t as good as it once was, I’ll keep an open mind and wait to see if my impressions change over time.

Ubuntu 10.10 and Citrix

Many of us with the opportunity to work from home will have met up with logging via a Citrix server. With that in mind, I set to getting an ICA client going on my main Ubuntu box at home. There is information scattered about the web in the form of question on the Ubuntu forum and a step-by-step guide by Liberian Geek. To summarise the process that I followed here, you have to download a copy of the Citrix Receiver installer for Linux from the company’s website. There, you’ll see DEB and RPM packages along with a tarball for other systems. The latter needs a bit more work so I got the x86 DEB package and installed that in the usual way using Ubuntu’s Software Centre to do the installation following the download. Needing to start the Citrix connection via a browser session meant that a browser restart was needed too. That wasn’t the end of the leg work because Thawte certificate errors were to stop me in my tracks until I downloaded their root certificates from their website. Once the zip file was on my PC, I extracted it and copied the required certificate (Thawte Server CA.cer from the thawte Server CA directory) to /usr/lib/ICAClient/keystore/cacerts on my system; it helped that the error message had told me which was the one I needed from the collection in the zip file. With that matter addressed, the connection happened without a glitch and I was able to get to working without recourse to a Windows virtual machine. For once, Linux wasn’t to be excluded from one of the ways of using computers that has been getting more prevalent these days.

Update 2012-04-14: On an equivalent installation on Linux Mint Debian Edition, I found that the installation location for the certificate had moved to /opt/Citrix/ICAClient/keystore/cacerts. This was for the 64-bit edition.

Update 2012-12-17: The above applied to an installation of version 12.10 on 32-bit Ubuntu GNOME Remix too.