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Security when transferring files - passwordless ssh or rsync daemon?
by Chris Green 04 Jun '14

04 Jun '14

I want to copy files from a BeagleBone Black (running Ubuntu) to my home dmz system. This has got to work unattended as the BBB is sat on our boat moored on the Somme. It's also got to be a 'push' from the BBB as it's connected via WiFi and while I can connect to it through an ssh tunnel copying files via that connection would be decidedly tricky. So, as I see it, I have two obvious options:- 1 - Set up a public key login for the BBB on my dmz that requires no passphrase, so it's effectively passwordless. Then the BBB can run rsync to copy the files. The security hole in this approach is that if someone accessed the BBB then they could login to the dmz without further difficulty. 2 - Run an rsync daemon on the dmz and copy the files by connecting to this from the BBB. The advantage is that someone at the BBB end can't do anything but copy files (and I can limit what can be copied with the rsyncd configuration), the disadvantage is that the connection isn't encrypted at all. There's nothing valuable in the files, they're just temperature and electrical measurements from the boat so I don't care at all about the files being visible to the world. My security concern is to minimise the risk of someone getting into my dmz system. OK, it's a dmz and it's just a Raspberry Pi so is hardly full of valuable data but it would be a nuisance and *might* be a jumping off place for further nefarious deeds. I guess I'm being a bit paranoid really, the BBB on the boat is headless and anyone breaking into the boat is hardly likely to be an accomplished Linux hacker. Option 1 above is certainly the easiest as rsync daemon takes a bit of setting up. Are there any really obvious flaws - is it only really vulnerable to someone who accesses the BBB? There is an option 3 but it's more difficult to set up, I could implement a passphraseless rsync connection from the BBB to the dmz that only allows rsync file copying to a specific directory. I've done this on one other system and it works pretty well (you do it by adding a command= at the front of the authorized_keys file) but like the rsync daemon it takes a bit of setting up and I'm wondering if it's worth the effort. Any comments anyone? Are there more obvious and/or easier ways of copying files without making systems vulnerable to other attacks? -- Chris Green

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27U rack looking for a new home
by Adam Bower 04 Jun '14

04 Jun '14

At work we have a 27U rack cluttering up our office, it has front and rear doors, some fans in the top and is on wheels to make it easy to move around. For this wonderful item I hear you say "but how much does he want for such a lovely thing?" well, the answer to that is, it's free if you come and collect it from Cambourne business park (8 miles west of Cambridge). Please mail me off list if you are interested, I have offered it around a few other places so it will be first who is able to collect gets it. Adam

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2600 meeting at 18:00 on Friday the 6th June.
by Viperfang 03 Jun '14

03 Jun '14

Quick heads up about this months Norwich 2600 meeting, more info at http://www.norwich2600.co.uk

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Probably OT: Using a wifi connection as a WAN
by Mark Rogers 28 May '14

28 May '14

I'm not sure if this is simple or not; if not then the solution is almost certainly going to use a Linux box so this might be on topic, but if not I can't think who else to ask. In my office I have a Draytek router, connected to ADSL (was O2, now Sky), with it's WAN port connected to another ADSL router, itself connected to PlusNet, and load balancing between the two. I have it set up this way due to the pretty useless speeds we get here (I just ran a speed test and got 3Mbps up, 0.5Mpbs down). No prospect of it changing much either in the short term. On the other hand, the same speed test on my phone shows 20Mbps down, 8Mpbs up (4G on Three). And I have free unlimited data including tethering. So I want to find a way to tether my office network onto my phone when I'm in the office. Is this just as simple as replacing the second ADSL router with an access point, or do I need to be more clever than that? (Also: the Draytek has a USB port for (eg) a USB 4G dongle, but could I use a USB wifi dongle to tether to my phone instead?) The "right" solution is to get a 4G dongle for the Draytek, but data plans on data SIMs don't seem all that great - and even phone contracts aren't as good as they were (I get unlimited tethering, but new contracts limit to 5GB while tethering). So I'd like to find a way to use my existing phone connection if I can, albeit that it's going to kill my battery when I use it. Although if anyone can point at decent 4G data plans instead I'd be happy to switch (I am already paying for two ADSL lines so I can ditch one of those if I get this working). (Apologies to anyone who would kill for the 3Mbps I currently get!) Mark -- Mark Rogers // More Solutions Ltd (Peterborough Office) // 0844 251 1450 Registered in England (0456 0902) @ 13 Clarke Rd, Milton Keynes, MK1 1LG

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Does NFS across subnets need to be able to 'see both ways'?
by Chris Green 28 May '14

28 May '14

As part of my improving security exercise I have implemented a DMZ system on a subnet separate from my main home subnet. Thus I have (similar to Mark Rogers) the following:- Draytek Vigor 2820n on subnet 192.168.1.0 WAN1 ADSL connection WAN2 Ethernet 192.168.13.0 to second ADSL router I have a Raspberry Pi plugged into to the second ADSL router's LAN so it's on the 192.168.13.0 subnet, this is the DMZ machine which will have a number of ports open to the internet. The 192.168.1.0 firewall doesn't allow any connections from the 192.168.13.0 subnet, but the Draytek Vigor 2820n does route anything addressed to 192.168.13.0 to WAN2. Thus for example I can ssh from my desktop machine on 192.168.1.0 to the Raspberry Pi. Now (finally!) to the question, can the Raspberry Pi export its files to my desktop (or anything on the 192.168.1.0 subnet) without opening up any holes in the firewall? I tried the obvious:- / *(rw,async,no_subtree_check) on the Raspberry Pi but although I could mount the filesystem successfully on my desktop any attempt to access it just hangs. -- Chris Green

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Decent player wanted for internet radio streams (specifically BBC)
by Chris Green 28 May '14

28 May '14

I'm looking for a way to (simply) play BBC Radio 4 and other BBC stations on my desktop machine. I used to use radiotray but updating to xubuntu 14.04 seems to have broken that completely (it was always a *bit* flakey). I don't want a full blown music player really, though one that's easy to configure to play BBC would be OK. I *definitely* don't want a list of thousands of stations to select from which rarely includes BBC anyway, I just want to be able to enter a BBC radio URL and hear the radio. I have clementine installed but I can't see how to get that to play URLs, it looks like it should but seems to be broken when you try it. Like so many other players I've found. -- Chris Green

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Would someone burn a distro for me?
by James Freer 24 May '14

24 May '14

My PC I think has a faulty DVD drive/corrupted installation as it doesn't seem to burn. My spare machine with a CDROM doesn't seem to work now and for some odd reason neither boot on the USB (even with PLoP). Not been a good day! If someone is prepared to help me out maybe you can reply off list - I live North of Bury. The distro is Fedora xfce and Salix (CDs as opposed to DVD). thanks james

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Fwd: Re: Overheard in the bar
by RustyHinge 24 May '14

24 May '14

Apropos Chalk Hill? -------- Original Message -------- Subject: Re: Overheard in the bar Date: Sun, 18 May 2014 12:53:41 +0100 From: Znep <E-0C001302-5256-E(a)cleopatra.co.uk> Organization: None, really.... Newsgroups: uk.rec.sheds etc. In uk.rec.sheds, (Murff) wrote in <ll917d$q4k$20(a)dont-email.me>:: >On Sun, 18 May 2014 01:58:53 +0100, Mike Fleming wrote: > >> I've had some that's been good and >> some that hasn't coped so well. > >Just finishing some Naylor's Old Ale, from Kildwick. About 1 mile from >here, bought by the case from the brewers. At that distance, whether beer >travels or not is rather less of an issue. Um. I once took a mate of mine to the Lass o'Gowrie, and had a pint of their finest- which I rather liked. He didn't. "Where's this from?" he asked. "They make it out the back, there." "Huh. Doesn't travel well, does it?" -- Marc

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I haven't tried *really* hard, but...
by Anthony Anson 19 May '14

19 May '14

Thunderguts is set to read Usenet offline. Posts for only one group are duly downloaded, but try to access them? Every time I try to open one, the cursor on the newsgroups column goes to the next one, where there are, of course, only headers. Is this a feature? Or am I doing something silly? -- Tony http://www.girolle.co.uk/

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Re: [ALUG] Is there any point in using an 'unusual' private IP address range for security?
by Phil Ashby 18 May '14

18 May '14

On 18/05/14 12:00 Chris Green <cl(a)isbd.net> wrote: > ... > What I'm thinking of doing to improve my security (or at least reduce > the likelihood of a break-in doing much damage) is to have a dedicated > 'dmz' server on the LAN/WAN between the Speedtouch router and the > 2820n's WAN port. I can then open up the appropriate ports on *that* > system to provide access from the outside world but if someone breaks > in they won't be able to see anything much except that machine and a > couple of routers. This would be a "good thing" (tm), provided there are appropriate firewall settings on the 2820 that prevent connections from the DMZ back into the house network (ie: treat the DMZ as the internet from the house network point of view). > My question is about what private IP address ranges to use, currently > they're as follows:- > > 2820n - 192.168.1.1 > This has *everything* hanging on it, backup NAS, family > computers, media boxes, etc. > > Speedtouch - 192.168.13.254 > 2820n WAN - 192.168.13.65 (assigned by Speedtouch DHCP) > New dmz computer would be added to this LAN > > > Would it be worth changing things around so that the Speedtouch LAN is > 192.168.1.x (the almost universal default for home LANs) and the 2820n > one is 192.168.13.0, or even 10.0.0.0 or 172.16.0.0 so that an > intruder is less likely to guess that there's another LAN to look for? > I know this is 'security by obscurity' to some extent but it's no > effort really except some minor configuration changes to some static > addresses and DHCP servers so if it offers any advantage it's probably > worth doing. Prior knowledge of internal network addressing may help someone prepare a drive-by attack on your 2820 via your browser, otherwise there won't be much extra protection once they are on the DMZ host and can see all the network traffic passing by. Phil

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