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FON fixes maps vulnerability, and why Martin should apologize

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You probably remember the post I made regarding FON’s figures, and how much I thought they differed from reality. It got quite a lot of attention, particularly from detractors, and from Martin Varsavsky himself. Many comments were posted on my blog and some others, which pointed towards the fact that I am involved in a startup which supposedly is a clone of FON, and thus I was biased and in no position to comment on FON. To cut a long story short, Martin posted a rather vicious personal attack on his blog, which I answered, he counter-commented, to which I again answered, but he never conceded a bit.Fon Maps

During my investigations that led to the statistics post, I also discovered a serious flaw in the maps management system, which would allow anyone to re-position any FON hotspot and change its address without first logging into the user area.

All that was required was the node’s ID and the hotspot owner’s user ID, both easily obtainable from the public queries that maps.fon.com launches against the database where hotspot data is held, and which I used to gather the statistics. For a determined attacker, it would have been very easy to place every single FON hotspot right in the middle of 1600 Pennsylvania Avenue, Washington DC.

I could have very easily posted about this, but I refrained from doing so for a reason – while I do not work full-time in the IT security industry, I have done quite a bit of consultancy work in the past, related to IT security, particularly in the wireless field. This means that I am fully aware of the industry-approved vulnerability disclosure procedure, which can be explained simply as:

  • Document the vulnerability, and inform the company about the fact that you have found it.
  • Wait for an initial response, establish contact points, and work a schedule for fixing the issue.
  • Work with the company to help them solve the issue.
  • Once the issue has been fixed, make a public disclosure on both sides about the vulnerability, giving credit to the person or company that discovered it.

You can find more references to this policy at Microsoft’s Security Response Center, here and here. A PDF from oisafety.org also describes this process in detail. A perfect example on how not to do things is the recent disclosure of a code injection vulnerability, which allowed manipulation of FON’s routers without even having to open them – even though their points are valid, they should have given FON the chance to fix the problem before going public.

In this case, I contacted FON’s support email first September 27th, and received a response on the 29th. This was really generic, only wanting to know about the details, and not acknowledging the normal procedure as I have explained above. On October 2nd, I emailed them again, asking to confirm that they understood the procedure, and on the 3rd they replied that they agreed on following the procedure.

I started compiling the information I had into a working document, but after becoming so frustrated at the attacks received as a result on my post about the statistics, the decision was to simply let the issue go, forget about FON, and concentrate on my own project. A couple of days ago, browsing around for stuff to clean up on the laptop, I came across the half-written report, and decided to finish it and send it to FON support, with CC to Martin, just to close the case. I received a reply today that they have in fact fixed the vulnerability, with a short ‘thanks’ (actually, quoting his email in full: “thanks Mike, i understand its been fixed”) from Martin.

The public acknowledgement of the discovery posted by FON is found in this forum post. Only in the English forums, by a user created apparently for this particular purpose, as this is his first post ever, where it is not likely to draw much attention. This would be fine by me, had not there been the precedent of Martin’s fierce replies to my statistics post, followed by countless attacks by FON’s followers, including an unfortunate incident better left forgotten. What I really cannot understand is that, when I criticize FON, I get such a huge public lashing, whereas when I help them out, I get a three-line remark in a forum where it will go mostly unnoticed. The end result may well be that other vulnerabilities, and it is likely they exist, go unreported.

Whatever the case, this should show those who accused me of unfair, biased attacks on FON that I really just call the shots as I see them, when I smell bullshit, I will point to it, when I see a hole, I will help them fix it – again, IMHO, blogging is not about being or not biased, it is about being ethical and maintaining a set of standards. In my view, it should also prompt Martin to write an apology, but I am not holding my breath. Not that I care much either, what is most important is my work; this is my blog, where I spend part of my spare time, which is not actually that much.

Conference WiFi IS important

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Robert Scoble writes about whether having a decent WiFi connection at a conference is something that important, and concludes that if you can afford the $3500 price tag to get in, you can also afford a $80 a month Verizon mobile data plan. Ethan Kaplan thinks it is important, and I agree, but for different motives.
What Robert fails to appreciate is, that while Web 2.0 may be more US-centered in terms of visitor origin, there are many conferences where the bulk of atendees come from abroad. In this case, it makes little sense to get into a Verizon plan just for the few days when you are visiting. Roaming data charges (when roaming data connections such as GPRS even work, which I found impossible around California) are astronomical.

I am in favor of event organizers providing a good quality, solid and stable WiFi connection, even though it can be very expensive. An example was the WOMMA conference at the San Francisco Hilton, which didn’t provide WiFi, as the hotel wanted $20.000 to put a router in the hall. However, a compromise between the two postulates would be for Verizon to offer a rent-a-card service. Just like I pick up my car at Hertz for a week at SFO, I could also pick up a Verizon card, use it while moving about, and return it at the airport before leaving the country. I can already hear critics saying “but people would just keep the cards” – maybe, but what good would they be to them? Additionally, just like you have a retainer placed on your credit card when you rent a car, the same could apply to the card, if you don’t return it, Verizon actually could make more money!

Autopsy of a Fonera

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Yesterday, I posted a few pictures of the opened Fonera, with a few initial views on the device. When I tried to plug it in, it failed to work, only the power LED lighting up. Neither the WiFi signal was coming up, nor the ethernet port was tickling the switch.

The only course of action? To open it up even more. So, the aluminium chassis came off, and that’s when I realized I had seen this before. The WiFi section, which includes the Atheros AR2315, crystal, filters, power amplifiers and ancilliary circuitry are housed inside this casing, and correspond to a reference design provided most likely by Atheros themselves. Check out the Meraki Mini router. For reference, I provide a side-by-side picture below (click for large image).

Meraki Mini vs Fonera

There is nothing wrong with using reference designs per se, as it is the fastest and easiest way to bring a product to market. If you don’t need to customize your design much, simply use what the manufacturer suggests, and you will be playing on the safe side. A perfect example is Bluetooth headsets, where CSR dominates the market. Virtually all headsets in the market use their reference design, with very little changes between them, other than physical placement of LEDs and buttons.

Block-by-block, here is an overview of the Fonera.

Power

Power is supplied to the Fonera via jack SK1, and is fed through a rapid fuse (Polychem type) to a simple drop-down regulator, which drops voltage from around 5V (4.85V as measured on the wall power supply, using a Fluke 179 multimeter) to 3.3V. The regulator appears to be an AME1117 (though the package markings read AME117), in its CCCT configuration, TO-252 form factor. The regulator is stabilized using three electrolyic capacitors. In these types of regulators, ESR (equivalent series resistance) of the input decoupling capacitors is very important, and this can usually be controlled nicely with tantalum capacitors. These are very expensive compared to electrolytic, however.

There is a second stage of regulation, this time done by an Anpec APL1117, which further drops the voltage to 2.5V. This supply appears to be used by the wireless subsection. Two ceramic capacitors stabilize the regulator.

Without the Atheros chip in place, the PCB drew 90mA at 5V, or 450mW. Since the device was not functioning, the total supply current with WiFi active could not be determined.

Memory

Two memory ICs are available on the Fonera, the first is an ST M25P64 serial flash, with a 50MHz SPI bus and 64Mbit capacity (8MB), in 300mil SO16 format. The fact that SPI has been chosen has the advantage that extra memory devices could be attached to the bus, but it has the caveat that it is slower than a parallel bus. Thus, flashing a new firmware could take a rather long time. Interestingly, there are two footprints on the PCB, presumably to fit a different size and format memory IC, one SO16 and one SO8.
The second memory IC is a Hynix HY57V281620E synchronous DRAM, with a capacity of 128Mbit organized in 16bit blocks. In practice, this results in 16MB of RAM available to the processor.

Ethernet

At the heart of the wired ethernet subsystem is an Altima AC101 ethernet transceiver, capable of 10/100 full duplex operation. The IC is placed on the bottom layer of the PCB, and runs off a 25MHz crystal, strangely placed next to the main power regulator, where it could absorb electrical noise. Usually, crystals are placed well away from sources of interference. Nothing else too exciting here, the transceiver is connected to a standard RJ45 socket, TP1.

Wireless

The wireless section is the most interesting. This is where the Atheros AR2315 single-chip WiFi processor lives. Little public information is available about this or any other Atheros chipset, so it is hard to figure out exactly how it is put in place, but a few details are clear.

First, the chip gets hot. This is why a double heat-conductive adhesive tape bonds the surface to the metal cover, and in turn to the heatsink placed on top. The processor runs from a 40MHz clock source. After the Atheros core, come a couple of filters, and a power amplifier stage. This then runs off to the two antenna tracks. The first antenna exits the aluminium cage and runs up to a test connector. This connector breaks the antenna track when the right mating plug is inserted, which is then fed into a dedicated RF analyzer, which validates that the device is within constraints.

After the antenna test point, there is a split, which can be configured using a zero-ohm resistor, to run to an internal solder pad, or to a PCB-mounted right-angle SMA connector. It is unclear why they chose to use the solder pad, as an in-place soldered connector needs less handling than soldering a pigtail by hand. Besides, my intuition tells me the losses would be lower – I will test this when I get a working Fonera. Both tracks run through an impedance matching network, consisting of two capacitors to ground from the RF track, and an inductor between the capacitors . The purpose if this small circuit is to get the impedance of the PCB track as close to 50 ohms as possible. If the track impedance is mismatched to the antenna, losses take place.

The second antenna runs straight to a PCB pad, where a pigtail may be soldered, also passing a matching network. Below is a picture showing the details of this subsection.

Fonera - WiFi subsystem in detail

Interfaces

There are two IDC-style connectors on the PCB, one 2×5, and one 2×7 but unpopulated. The 2×5 looks like a serial connector, as only power, ground and two tracks lead out from it. The layout has to be studied in more detail to confirm this assumption.
It can be speculated that this is in fact a serial port, but without the AR2315 pinout, this cannot be determined for sure. The 2×7 header seems to be a JTAG interface, possibly compliant with MIPS EJTAG 2.6. The mapping of the header pins to the AR2315 BGA balls is shown below (thanks for adding a row/column silkscreen for the Atheros chip, and thanks to the OpenWRT project wiki for the JTAG information!):

Fonera - JTAG connector

Between the Ethernet jack and the empty SMA footprint, there is a footprint of 6-way header, which needs a bit more study to determine where it leads internally [I will update the post when I find out –Mike].

Conclusion

This is a very compact and simple WiFi router, designed not for being easy to hack, but for lowest cost. The cheap power regulator, use of large SMDs and choice of pigtail rather than board-mounted SMA connector point in this direction. There is only one port which could be used for something useful, if it is indeed a serial port, the only two GPIOs available being the WLAN and Ethernet LEDs – as long as the Ethernet LED is not controlled by the Altima but by the Atheros. The power LED is on as long as there is power applied to the device, so there is no control over this by the Atheros processor. Power consumption is a bit high, considering the wireless device was not present. The PCB layout is very professional, except in a few particular cases such as the large crystal, but overall, quite nice.

In all, a very small device which could have a lot of potential, had it not been for its lack of I/O. It is unclear whether the router will accept custom firmware, as there are rumors that an encryption & signature system is used. The Fonera is probably OK for regular use by Foneros, but it does not have the hackable edge of the Linksys WRT54Gx. The only suprise could come from the edge connector, as of yet of unknown usefulness.

References

Atheros AR2315 chipset website section and product brief.

The naked Fonera

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After a few days of silence, digesting the hubbub created by my analysis of Fon’s status, I’ve put my head back into more useful things than answering hate mail and out-of-line comments (thanks to those who provided balanced views, either for or against!). So, I decided to open a Fonera and see what lives inside.

A full review is coming, but first impressions:

  • The plastic casing looks and feels very nice, the molds must have been expensive, as the different parts mate very well.
  • Inside lives a single PCB, with components on both sides. The top holds the bulkier components, such as power regulator, RAM and WiFi section, inside an aluminium RF shield.
  • The PCB looks professional and well laid out on first inspection.
  • Components used (I haven’t opened the aluminium chassis yet) are older SOIC and TSSOP, thus cheaper to handle and solder. Balled components require from special handling, such as baking in hydrogen for 24 hours to dry them before soldering, etc.

Here are some pics (click each photo for bigger views on Flickr) I have taken with a Nokia N93 (really nice phone btw, mini-review coming):

Fonera - underside of casing

The underside of the case, with screws off.

Fonera - perspective view

Perspective view of the top PCB.

Fonera - Bottom PCB

Bottom side of the PCB.

Fonera - firmware version

Sticker on the flash IC showing the firmware version.

The real FON statistics – lies, manipulation or fantasy

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On September 14th, FON launched the new version of their online mapping service, after several months of complaints from users that the service wasn’t up to scratch, and announcements stating the development team was working on the problem.

On a first look, the maps look really nice – they use Google Maps, by default in the mixed view, where you see a satellite image and an overlay of roads and placemarks. I will not bore you with the details, as it is better that you check them out yourself and make up your mind.

This post is not intended as a review of the service itself, but rather, a revelation of the real figures behind FON’s network – peeking under the layer of PR and flamboyance. Martin Varsavsky is always boasting about FON being the largest WiFi community of the world – in my view, this is not accurate.
During months, FON has been claiming to be a “movement”, with a marked communist image behind (the marching workers, the spray-painted logos, etc.). This movement was supposed to kill mobile operators, who currently oppress people with their sky-high tariffs. We could go into a long debate just on this topic, but lets move on. During all this time, FON has suffered untold problems with staffing, PR mini-scandals, shipping broken routers or taking weeks and months to even send them out, not replying to repeated requests to support@fon.com, and blatantly ignoring the public forums, where the community behind the movement was expressing its increasing anger and frustration.

The blinding truth – less than 3.700 routers online worldwide

Digging a bit deeper into the workings behind the maps, I have found that there is a method to run a query to retrieve all the hotspots in FON’s database, not just two hundred, or those in a particular region. If you want to see an example, click here. This is a query that will return all hotspots on the planet that have been FONing home during the last hour. It can take a little while to load, so be patient. Until a couple of days ago, results were returned in XML format, which has been dropped in favor of the new plain, comma-delimited format.

I predict that FON will not like the above link, and thus will try to either change the format of the php call, or add artificial records to confuse the application I have written to process the data. First, I wrote a simple application using RealBasic (having been a long-time Visual Basic acolyte, it is a welcome change, allowing me to code under Mac and Windows transparently) – source code here. A screenshot of a full run is shown below.

Application screenshot

Just from the details shown after the run, a few enlightening facts surface:

  • The highest user ID found is 92.192, but the total amount of processed records is only 55.384. I have to investigate a bit further, but it appears that in some cases, a record is stored twice, once holding the user type (Linus, Alien or Bill), and again holding the router mode (online or unknown). This is the reason why some people see both the orange dot and the green halo on their locations at maps.fon.com, and also the reason why at this time I cannot confirm that the real number of Foneros is 43.896.
  • There are only 3.674 routers online on the entire planet. So much for the largest WiFi community in the world. The other 7.814 are registered routers, from which nothing has been heard during the last hour. These figures have been checked a few times during the last few days, and they stay more or less constant.
  • Out of the entire user base, only 1.317 have become Bills. So much for milking one’s WiFi.
  • The highest router ID found in the results was 19.889, so if we add offline and online routers (best case scenario), then around 8.401 routers have never been registered, representing 42.2% of sold routers. Extrapolating this to the 1 million routers Martin wants to sell would results in a loss of $10.55 million!.

Looking at the per-country statistics (per-city could be made, given some extra time and coding), some curious details also stand out:

  • There are two registered routers in Afghanistan – but neither is online. Not surprising, considering the amount of explosives that have been dropped on the place.
  • China and Taiwan have 9 routers registered, but none online. Martin was blogging about his expansion into Asia, which looks rather bleak right now. 165 Foneros are registered however.
  • Germany and Spain have around the same number of registered routers, although Germany almost doubles Spain in the number of online routers.
  • The United States ranks third in number of registered and online routers, however, it holds the highest number of Bills (408). The next is Germany, with 237.

Finally, we can derive a few figures from these numbers. These are highly interpreted, and must be taken as theoretical extremes.

  • If FON sold one $3 one-day pass every day of the year on each of the online routers, it would make a gross income of $4 million. This is before tax and the Bill’s share where applicable. You at the back, stop giggling!
  • Making a wild assumption that each router’s signal reaches 100 people, FON would only cover 0.11% of Germany’s population of 82 million.
  • Boingo gives you access to 45.000 hotspots. FON has about 8% of that figure, and with location quality debatable – it is a fact most FON hotspots will not be optimized for even street-level coverage.

I believe it is time for FON to stop boasting about having the largest WiFi community in the world, and start concentrating on its real problems. And if they still don’t know what these are, they have a nice summary at the online forums. Besides, for spending 500.000 Euros per month, this is a pretty poor show, in my humble opinion.

Digi – an example of excellent costumer support

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What do you do when you need to embed WiFi into a project really quick? You look for OEM modules – one of the best manufacturers being Digi. They make, amongst other variations, the Wi-ME, a small box that has a RTOS chip (it can be made to run Linux apparently) and the WiFi adapter, with a serial interface and GPIOs that go to your application. In essence, you can bridge a serial port to a TCP or UDP port and stream data to the internet, all without messy wires!

After looking at the ordering page, I duly contacted the spanish distributor Matrix. I needed two modules by this last Monday, and so I requested to have the devices shipped by Friday last week. It all turned out into one big mess, with vague excuses about not being able to ship due to warehouse problems, or that the proforma could not be generated – and so I could not pay, and they could not ship…to cut a long story short, I got the units on Tuesday.

It usually is not a problem to have a shipping delay, but in this case, I arranged a meeting with the mechanical engineers working on the project, in order for them to see the device and fit it into the 3D plastics project. They actually measure the parts, as they say working from datasheets can usually spell trouble, so ideally they would take them away after the meeting. Had Matrix simply said “we cannot send it until Monday”, I would have arranged the meeting on Wednesday – no worries. But, as it frequently happens, they wanted to look good, without having the solid ground under their feet to do so.

When a company makes a commitment, whatever it may be, it has to stick to it. And when the costumer calls, obviously pissed off at the poor performance and the mount of problems he has landed on, you have to be hellbent on fixing the situation. If the person answering the phone cannot handle the situation, he/she must be trained to transfer the call to someone who can.

What did I do? I emailed the CEO, Joseph Dunsmore. His email address is not published on Digi’s site, but if you look on the Management Team page, and scroll down a bit, Jan McBride’s email is displayed. It was a case of formatting Joseph’s name in the same manner as Jan’s email, send the diatribe, and wait. The next day, I got a reply from Joseph, telling me he would follow up the case with Digi’s Managing Director in Europe. Not three hours had passed, and I got a call from Digi’s top man in Spain, who was very supportive and understanding. By this time, I had been so smoothed over, that I really didn’t want to complain anymore! The conversation ended up very well, with Digi offering their full support on our development, and a visit arranged sometime next week.

Would I recommend Digi to anyone deciding about whether to use their products? Absolutely!