[HN Gopher] Starlink User Terminal Teardown
       ___________________________________________________________________
        
       Starlink User Terminal Teardown
        
       Author : walterbell
       Score  : 275 points
       Date   : 2025-05-09 03:03 UTC (19 hours ago)
        
 (HTM) web link (www.darknavy.org)
 (TXT) w3m dump (www.darknavy.org)
        
       | walterbell wrote:
       | https://web.archive.org/www.darknavy.org/blog/a_first_glimps...
        
       | latchkey wrote:
       | Discussions on similar submissions:
       | 
       |  _Teardown of the SpaceX Starlink User Terminal_
       | https://news.ycombinator.com/item?id=25277171 (December 2, 2020
       | -- 158 points, 138 comments)
        
       | londons_explore wrote:
       | I'm surprised to hear all packets are processed in userspace...
       | 
       | If one is doing 1Gbps of traffic which is 100 byte UDP packets,
       | that's a million packets per second you're gonna need to process.
       | 
       | A 1Ghz CPU only then gets 1000 cycles to process each one...
       | 
       | Very doable, but certainly not easy unless your engineers like
       | hand coding assembly and having to think about every lookup table
       | trick in the book...
        
         | hackernudes wrote:
         | > Drawing on existing research [3], our preliminary analysis of
         | these programs and configurations suggests that the network
         | stack architecture is somewhat similar to DPDK [4], mainly
         | relying on a user-space C++ program to bypass the kernel for
         | handling network packets.
         | 
         | The way it usually works is that the initial packets are
         | handled in software but once the endpoints are established it
         | flows through hardware. Sometimes certain patterns are always
         | handled in software. The software could be a patched kernel or
         | a XDP style kernel bypass.
         | 
         | Source: worked peripherally on an Intel Puma cable modem
         | router/gateway that used DPDK or something like it. So I'm not
         | 100% sure, but it is an educated guess.
        
         | riehwvfbk wrote:
         | Why would it be any less efficient than processing the packets
         | in the kernel? There's a way to map the hardware queues into
         | userspace (the article talks about the system being DPDK-like).
         | At that point why does it matter that the polling code isn't in
         | the kernel?
        
           | londons_explore wrote:
           | Most hardware >100Mbps has hardware offload - ie. the
           | hardware is told which packets to send where, and software
           | doesn't touch individual packets (except rare packets like
           | ping).
        
             | Hikikomori wrote:
             | Not really, you can easily find CPU only routers in every
             | product segment from home routers to enterprise for that
             | speed, even many years ago.
        
             | riehwvfbk wrote:
             | Yes, but you can have GSO and GRO in combination with
             | userspace protocol processing.
        
         | rapsey wrote:
         | > which is 100 byte UDP packets
         | 
         | 100 byte?? Starlink has regular 1500 byte MTU.
        
           | Tepix wrote:
           | With RTP traffic you often have lots of small packets.
        
           | tuetuopay wrote:
           | In networking, it is the norm to measure performance in
           | packets per second, so with small packets. Unless you're
           | performing DPI or encryption, routers only use the headers to
           | take routing decisions, so whether the payload is 10 bytes or
           | 1000 bytes does not matter: the processing cost will be
           | identical. Only the hardware bandwidth will matter for large
           | packets, though this is rarely the issue (I've hit DDR4
           | limits once using XDP, and fixed by adding another stick of
           | memory);
        
         | dilyevsky wrote:
         | > I'm surprised to hear all packets are processed in
         | userspace...
         | 
         | Specifically for cases of forwarding DPDK-style approach can be
         | faster because it will incur fewer buffer copies.
         | 
         | Starlink only does 25-200Mbps and average packets are like 7-8x
         | larger so at most you're doing ~36000 PPS which is pretty
         | manageable even on 1Ghz
        
         | _joel wrote:
         | Doing it in userspace aviods another memcpy, it's much faster.
        
       | jwrallie wrote:
       | > During device initialization, if the system identifies itself
       | as a user terminal, the initialization script automatically
       | writes 41 SSH public keys into /root/.ssh/authorized_keys.
       | Notably, port 22 on the UTA remains open to the local network at
       | all times.
       | 
       | Forty-one? So who does _not_ have root access to  "your" user
       | terminal?
        
         | ronsor wrote:
         | You, of course.
        
         | yonatan8070 wrote:
         | You, probably.
         | 
         | On a more serious note, is this any different from ISPs having
         | a remote management system for ISP provided routers? In terms
         | of privacy, if SpaceX didn't have access to the user terminal,
         | they could still just capture your traffic on the sattelite or
         | the ground stations
        
           | ronsor wrote:
           | If they have access to the router, they can capture local
           | network traffic as well as internet traffic.
        
             | arghwhat wrote:
             | Note that such capture would be quite terrible for
             | performance, not only requiring disabling any hardware
             | offload (a great router might be able to route a few
             | hundred megabit in large packets without offload assuming
             | it _doesn 't_ do anything else) to make packets visible for
             | capture, but it would also have to stream the output back
             | to the adversary over the uplink as you would be limited to
             | at most a few gigabytes of local, extremely slow storage,
             | giving no means for local offline analysis...
             | 
             | The risk of access to the router is more that they can
             | access your network and touch unprotected and vulnerable
             | things rather than active monitoring.
        
               | db48x wrote:
               | And most of that wouldn't be useful. We use encryption
               | for almost everything now for a reason.
               | 
               | No, wiretaps on modern networks do not rely on backdoors,
               | or even big labeled front doors like SSH, on individual
               | subscriber devices. Instead it is built into the lower
               | level routing. When an ISP gets a warrant (or whatever
               | relevant document your country uses) they configure their
               | routers to tag all of your traffic and mirror it to a
               | server to be recorded. It's entirely invisible to the
               | subscriber, and highly automated.
        
               | tredre3 wrote:
               | > And most of that wouldn't be useful. We use encryption
               | for almost everything now for a reason.
               | 
               | The topic at hand is local network access. Some examples
               | of things happening on your local network that you might
               | not want Elon/ISP to see:
               | 
               | - Many people have public shares on their NAS for things
               | like media or family photos
               | 
               | - Security cameras
               | 
               | - Printers
               | 
               | - If you're casting, the title of everything you watch is
               | broadcasted on the network
               | 
               | - Even if you're not casting, if you use an Android TV
               | then the title of everything you watch is also
               | broadcasted to the network by default
               | 
               | - The list of all your devices
               | 
               | - If you torrent things, then the hash of all your
               | torrents is likely broadcasted to your local network
               | (through Local Peer Discovery)
        
             | edf13 wrote:
             | I sit my external routers (and Starlink) behind another
             | network (DMZ).
        
           | danieldk wrote:
           | _On a more serious note, is this any different from ISPs
           | having a remote management system for ISP provided routers?_
           | 
           | Maybe, but in more and more European countries, ISPs are
           | required to accommodate you hooking up your own router/modem.
           | E.g., I am on fiber and if I want to I can hook up my own
           | router directly to fiber with an SFP+ module (I currently use
           | the ISP-provided media converter, but my own router). Lots of
           | tech users use their own Ubiquiti/OPNsense/OpenWrt routers,
           | so no remote management.
           | 
           | I wonder if this requirement applies to Starlink as well,
           | since they are an ISP.
        
             | prajaybasu wrote:
             | As far as I'm aware, they are only required to allow you to
             | use your own router.
             | 
             | DSL tech is far simpler and it's always a combo unit so I
             | could see a case where you would be allowed to bring your
             | own DSL modem.
             | 
             | But it just doesn't work like that for DOCSIS or GPON where
             | the cable modems or ONTs these days do much more than just
             | media conversion - SIP, PPPoE, IGMP, etc. even if they
             | don't do Wi-Fi (so ISPs don't call them "routers" - except
             | SingTel, which uses "ONR" to distinguish these units
             | because they are in fact routers for IPTV and SIP).
             | 
             | For all of those modems/ONTs, the firmware updates and the
             | configuration for telephony/SIP and PPPoE are controlled by
             | the ISP and also tested to work with their OLT or CMTS so
             | it's just not possible for the ISP to guarantee support for
             | any random modem or ONT.
             | 
             | And to support the advanced configuration required these
             | days for VoIP, IPTV, etc. on the "modem" or "ONT", ISPs
             | basically have a backdoor called TR-069 which is really not
             | too dissimilar to what Starlink has access to with their
             | SSH keys.
             | 
             | Even if you get "true" dumb modems or ONTs which do not do
             | any routing whatsoever, the device on the other side still
             | has full control over your dumb device via the DOCSIS
             | provisioning process or GPON's OMCI. Starlink seems to be
             | using SSH instead of building a whole protocol - because
             | satellite tech is proprietary and doesn't need to work on
             | other hardware.
             | 
             | So, I find that it's highly unlikely that the ISP is
             | officially required to support a user supplied modem,
             | although I haven't consulted the EU laws on this.
             | 
             | At most, I think using your own router would require the EU
             | ISPs to provide bridge mode support, but that's not special
             | to EU. However, the TR-069 backdoor is still active even
             | with bridge mode.
             | 
             | It can be fairly easy to stop TR-069 with a "dumb" ONT
             | (usually SFP) but ISPs can and will notice that. Whether
             | they allow it is up to them.
        
               | bkor wrote:
               | > So, I find that it's highly unlikely that the ISP is
               | officially required to support a user supplied modem,
               | although I haven't consulted the EU laws on this.
               | 
               | Ziggo (called UPC in other EU countries) uses DOCSIS. The
               | instructions on how to use your own DOCSIS modem are at
               | the following link (in Dutch):
               | https://www.ziggo.nl/klantenservice/apparaten/wifi-
               | modems/ei...
               | 
               | Edit: it really is using your own modem. It's not about
               | putting it in bridge mode.
        
               | donnachangstein wrote:
               | "Your" modem is netbooting "their" firmware and they have
               | full remote access on a management interface.
        
               | kotaKat wrote:
               | This. I can just provision in the backdoor interface on
               | the modem with a config file anyways and gain access.
               | 
               | Plus depending on model (like Arris modems), I can do
               | things like set the password of the day seed (away from
               | the factory default) to further lock it down and gain
               | management access remotely.
        
               | claudex wrote:
               | >DSL tech is far simpler and it's always a combo unit so
               | I could see a case where you would be allowed to bring
               | your own DSL modem.
               | 
               | Not really, when you want to increase the bandwith, e.g.
               | with vectoring[1], you need to have all neighbor modems
               | to participate, which prevent free modem choice for the
               | users.
               | 
               | >But it just doesn't work like that for DOCSIS or GPON
               | where the cable modems or "ONT" router combo units these
               | days do much more than just media conversion - SIP,
               | PPPoE, IGMP, etc.
               | 
               | In Belgium, the ONT is just media conversion these days,
               | SIP is done on the provider box, so you can have your own
               | GPON SFP.
               | 
               | >so it's just not possible for the ISP to guarantee
               | support for any random modem or ONT.
               | 
               | The ISP doesn't have to guarantee support to let you use
               | your own hardware. It just have to give you the specs to
               | use it and let you plug the ISP box if you can't
               | configure vlan of dhcpv6 client.
               | 
               | [1]: https://en.wikipedia.org/wiki/VDSL#VDSL2_vectoring
        
               | claudex wrote:
               | Each country regulator in the European Union have to set
               | it's own regulation, but the BEREC (Association of UE
               | telecom regulators) guidelines say that in most case, the
               | free choice of router and modem is what's is required by
               | the EU decisions https://www.berec.europa.eu/sites/defaul
               | t/files/files/docume...
        
               | fx1994 wrote:
               | Provider will not support my modem that is for sure so if
               | you have any issues you are on your own. I use my own
               | Mikrotik + Zyxel PMG3000 GPON SPF and no issues at all.
        
               | chgs wrote:
               | Not the case in the U.K., dal or fibre doesn't matter,
               | domestically you typically have a standard sfp or other
               | converter from anywhere which presents it as Ethernet
               | which you then run pppoe over.
               | 
               | Tr069 allows the isp to remotely configure their
               | equipment which most people are happy with, but if you
               | want to use your own then that's fine, and obviously
               | unless you enable it the isp won't configure your router
               | or any other equipment.
               | 
               | Starlink acts far more than a media converter.
        
               | AnssiH wrote:
               | > But it just doesn't work like that for DOCSIS or GPON
               | where the cable modems or ONTs these days do much more
               | than just media conversion - SIP, PPPoE, IGMP, etc. even
               | if they don't do Wi-Fi (so ISPs don't call them "routers"
               | - except SingTel, which uses "ONR" to distinguish these
               | units because they are in fact routers for IPTV and SIP).
               | 
               | At least in Finland the norm is that you can use your own
               | DOCSIS modem from any manufacturer, you just tell the ISP
               | your modem's MAC address.
               | 
               | Not for GPON, though.
        
               | devmor wrote:
               | Same here in the US. You can bring your own DOCSIS modem
               | to any cable internet provider.
        
               | bombela wrote:
               | For me, Comcast only allowed a few models. Because it
               | requires full control. They uploaded a Comcast firmware
               | on it. And they warned me that after that the device is
               | basically stuck to only work with Comcast. This was
               | around 2017.
        
               | connicpu wrote:
               | On Xfinity you can BYO DOCSIS modem. It has to be from an
               | approved list of manufacturers, but I purchased my own
               | DOCSIS modem back when you had to do that in order to
               | receive gigabit internet service (it was still early days
               | of the rollout).
        
               | immibis wrote:
               | Modems are part of the ISP's network. Where does the
               | ISP's network end, and your network begin? You might be
               | tempted to say it's at the wall jack, but your ISP is
               | tempted to say it doesn't, and your computer is theirs
               | too.
               | 
               | In the past (and again on some fiber networks), there was
               | https://en.wikipedia.org/wiki/Network_interface_device
               | and the separation occurred there.
               | 
               | Note that it might not be the same at L1 and L2, e.g.
               | your ISP may own the physical lines up to the side of
               | your building, and the data link layer up to your modem.
        
             | donnachangstein wrote:
             | > I am on fiber and if I want to I can hook up my own
             | router directly to fiber with an SFP+ module
             | 
             | I don't think you quite understand how this works.
             | 
             | The ISP controls whatever the other end of that fiber is
             | plugged into. It doesn't matter if the medium is fiber, or
             | copper, or a piece of string. The ISP always has control of
             | the other side of the customer interface. It doesn't matter
             | if the box physically resides in your home or not.
             | 
             | In the case of Starlink, it's all contained within one box.
             | 
             | In the case of DOCSIS (cable), you may physically own the
             | modem, but the ISP controls the firmware it netboots and
             | has full remote admin to the device.
        
               | mattclarkdotnet wrote:
               | Owning the modem only gives them access to the link
               | layer. It didn't give them any access to my router or to
               | my https traffic
        
               | jmb99 wrote:
               | Do you think root access on your router gives access to
               | your unencrypted https traffic?
        
               | conorjh wrote:
               | depends
        
               | lupusreal wrote:
               | It gives them access to the LAN so they can, for
               | instance, figure out how many internet gadgets your house
               | has and sell that information to advertisers, or do even
               | worse than than.
        
             | miki123211 wrote:
             | Starlink is not an ISP in the traditional sense.
             | 
             | If a normal ISP wants to operate in country a, they need
             | infrastructure in country a. This means they either follow
             | country a's laws or that infrastructure gets seized.
             | 
             | Starlink could just as well be operating entirely from the
             | US, and there's very little that foreign governments could
             | do to stop them if they break some foreign laws. They could
             | make payments and shipping complicated, which is probably
             | why Starlink would rather comply if the requests are
             | somewhat reasonable, but Musk has indicated multiple times
             | that he's willing to stand up to unreasonable restrictions
             | if the need is dire enough.
        
               | ratatoskrt wrote:
               | This is not at all how laws actually work. If you sell a
               | product to customers in a specific country, you generally
               | have to comply with local laws. You might be able to
               | avoid this if you're very small and your service is
               | entirely virtual. However, as long as Starlink needs to
               | provide their customers with physical hardware, there are
               | numerous ways to enforce regulations.
               | 
               | And you can always go after people - and I mean both
               | Starlink executives and customers.
        
               | dangus wrote:
               | Right, if this is how it worked we'd have to explain how
               | companies like DeepCool and Huawei are banned from doing
               | business in the US.
        
               | zdragnar wrote:
               | Half of the EU have also banned ZTE and Huawei equipment,
               | so it's not just a US thing.
        
               | verzali wrote:
               | Some countries require you to have ground infrastructure
               | in the country to operate satellite systems. Starlink's
               | architecture also means they need to have a lot of ground
               | stations all over the place. They can skip some areas if
               | they need to and still offer service, but they'd
               | seriously struggle to provide a global service by using
               | only US ground stations.
        
               | bbarnett wrote:
               | Yes, but...The skinny is that the end goal is a massive
               | station on the moon, and a single, powerful downlink fron
               | there.
               | 
               | This is facilitated by two things.
               | 
               | First, we at Starlink are on the cusp of forcing light
               | into 'particle only' mode, or PAM. With PAM, as the light
               | is a particle, not a wave, it undergoes perfect time
               | dilation.
               | 
               | Thus, transmit time between the moon and earth is
               | instantaneous!
               | 
               | With this idea moderately solidified, we're preparing an
               | aggressive launch schedule, to get that hardware on site!
               | 
               | Starlink receivers will be able to transmit via PAM
               | too... once we've flushed out the tech.
               | 
               | All it will require is a series of future software
               | updates, so buy your Starlink now!
        
               | Hikikomori wrote:
               | Yesterdays technology. I'm working on light that ignores
               | matter, just beam through the earth.
        
               | conorjh wrote:
               | "They could make payments and shipping complicated..."
               | 
               | eg they could outright ban the sale of StarLink products,
               | ya know, being in charge of the laws and all
        
             | lupusreal wrote:
             | AFAIK, in America, ISPs are required to permit user-
             | provided modems as long as those modems are technologically
             | compatible. I believe the Television Viewer Protection Act
             | of 2019 did this, although it was already the norm for ISPs
             | to permit third party modems before this.. I guess because
             | they knew if they pushed the issue they'd lose anyway,
             | given the precedent of telephones, cable cards, etc.
             | 
             | The problem then with Starlink is nobody is manufacturing
             | compatible third party Starlink terminals, at least yet.
        
               | surfaceofthesun wrote:
               | I'm not sure if that applies to Fiber connections. I had
               | my own fun with a firmware update causing latency issues
               | with ATT Fiber's gateways that was fixed several months
               | later [1]. I was using the combo ONT + Router originally
               | and had to switch to dedicated ONT.
               | 
               | I ended up extracting 802.1x certificates with this[2] or
               | a similar tool and interfacing directly with the ONT
               | using OPNSense [3]. I was so angry I filed an FTC
               | complaint because I had to do this bypass to do my job
               | (the latency was so bad).
               | 
               | ---
               | 
               | [1] -- Linking to Reddit due to DSLReports going Down. ht
               | tps://www.reddit.com/r/ATTFiber/comments/1dwwh61/comment/
               | l...
               | 
               | [2] -- https://github.com/0x888e/certs
               | 
               | [3] -- https://forum.opnsense.org/index.php?PHPSESSID=t6v
               | vukft2ahga...
        
             | genewitch wrote:
             | No idea if it is required, but you can use a third party
             | router with starlink; and, in fact, must, if you want
             | routable ipv6. Ipv4 is cgnat no matter what.
             | 
             | I know this because I tested this.
        
           | amelius wrote:
           | I think the main problem is that they would have access to
           | other traffic on your local network. But you can just add
           | more hardware to isolate it.
        
           | _joel wrote:
           | Is https://en.wikipedia.org/wiki/TR-069 not available?
        
         | znep wrote:
         | I wonder who would be best equipped to see if any of those keys
         | are traceable to individuals involved in special government
         | affairs lately? There have been some good leaks...
        
         | niobe wrote:
         | could simply be 41 instances of the same server in 41 regions,
         | not necessarily a cause for concern. Starlink is a global
         | service after all. I'd be more concerned if 41 instances were
         | sharing one key.
        
           | MrOwen wrote:
           | Is that normal? I would imagine that if I were managing such
           | a large deployment, I would just use a CA for the keys and
           | then issue CA signed private keys so that I don't need to add
           | a bunch of random ones to authorized_keys
        
           | overfeed wrote:
           | > I'd be more concerned if 41 instances were sharing one key.
           | 
           | Dozens/hundreds/thousands of web servers servers can easily
           | share one _private_ key in a certificate, public keys offer
           | even more options on sane designs. Directly authenticating
           | _41_ servers using ssh-keys is just poor, slap dash
           | engineering.
        
             | gardenerik wrote:
             | Is it a better idea to share private keys? In case of
             | server breach, you will have a much harder time, won't you?
        
               | overfeed wrote:
               | > Is it a better idea to share private keys
               | 
               | It is not, amd I can't see how my earlier comment can be
               | read as recommending that. This is a solved problem for
               | _private_ keys (using load balancers, for example) , so
               | _public_ keys are lower-hanging fruit than that.
               | 
               | Edit: upon rereading, I cam see how the word "share"
               | would be ambiguous in the context of if a private key. I
               | meant "jointly make use of", rather than "distribute
               | copies throughout the fleet". I have exited my root
               | comment to make my meaning clearer.
        
               | ta1243 wrote:
               | A better idea would be the terminal trusting one or two
               | core certificate authorities and then those authorities
               | creating time limited certificates when needed.
               | 
               | So the terminal accepts "sshauthority1"
               | 
               | Then the 41 remote sites contact sshauthority1 to get a 1
               | hour (10 minutes, 10 days, whatever) long certificate for
               | "site18"
               | 
               | If a remote site is compromised sshauthority1 no longer
               | issues certificates, and within an hour (10 minutes, 10
               | days, etc) the remote site can no longer reach the
               | terminals.
               | 
               | Revoking a key from that many terminals (many of which
               | will be offline) if one of the 41 keys is exposed is not
               | trivial.
               | 
               | Now if sshauthority1 is compromised then you've got the
               | same issue with rotation (although can CRL it), but it's
               | easier to secure one or two authorities than 41 keys.
        
             | jmb99 wrote:
             | I would argue reusing private keys worldwide is slapdash
             | engineering. You generally want to minimize exposure in the
             | event of a breach, not maximize it.
        
               | overfeed wrote:
               | > I would argue reusing private keys worldwide is
               | slapdash engineering
               | 
               | I wasn't suggesting it, and frankly can't see how that
               | could be a solution in this instance. I was making a
               | comparison against current practices on a harder problem
               | to solve , i.e. safely scaling a single private key in an
               | SSL certificate across many servers is solved today
               | without a 1:1 server to certification ratio
        
               | petee wrote:
               | I wonder what the reasonable balance between reuse and
               | over exposure is; I'd think you would want less keys per
               | device, and have less key overlap (ie more keys overall.)
               | But forty two sounds high, and isn't it now just 42x more
               | at risk?
        
             | harrall wrote:
             | You're asking for something that is supported in X.509 but
             | OpenSSH wrote their own certificate exchange standard that
             | does not have support for those features.
             | 
             | HTTPS uses X.509. OpenSSH has no interest in supporting
             | X.509 or, AFAIK, for changing their version to support
             | anything but "self-signed" keys.
        
               | overfeed wrote:
               | > You're asking for something that is supported in X.509
               | 
               | There's more than 1 way to skin this cat, and no, I'm not
               | asking for the a specific solution you suggested.
               | 
               | SpaceX can implement any internal auth-scheme they choose
               | to connect to a handful (not 41) of SSH intermediate
               | instances, which then connect to the terminals
        
           | connicpu wrote:
           | Notably, I believe 41 is the current count for how many
           | points of presence starlink has around the globe.
        
         | sneak wrote:
         | I'm a single user and my authorized_keys is 25 lines. I have
         | different yubikeys in laptops, keys on iPads and iPhones, and
         | secure enclave keys on macs.
         | 
         | I imagine starlink has more than 1-2 sysadmins. I think a
         | hundred pubkeys would be reasonable.
        
           | tomalpha wrote:
           | It seems wrong that each individual sysadmin human in Space X
           | would need to (a) login to my device remotely, and (b)
           | require individual credentials to do so.
           | 
           | Having some way to remotely push updates, and having some
           | kinda of (preferably with your consent!) remote access might
           | be reasonable, but I would expect that to be via some kind of
           | intermediate gateway/app/something and not direct from a
           | sysadmin's individual account.
        
           | ta1243 wrote:
           | SSH Certificates is a far better approach even if that many
           | users needed direct access. It's not 1990 any more.
        
             | sneak wrote:
             | Certificates are great, but not strictly necessary until
             | you need to distribute thousands of keys. maintaining an
             | authorized_keys text file is much simpler than running a
             | CA.
        
           | e2le wrote:
           | I can't imagine why that would be reasonable for an
           | environment that demands a higher degree of security.
           | 
           | I imagine the most ideal situation would be 1) minimising the
           | number keys, 2) use hardware backed authentication or
           | certificate based authentication, 3) lock up the private keys
           | somewhere safe.
           | 
           | The idea of 41 points of failure that can SSH into any
           | starlink terminal is not appealing.
        
           | e12e wrote:
           | I think a single trusted ssh certificate would be more
           | reasonable...
        
         | e2le wrote:
         | It would've being interesting if they had published those
         | public keys.
        
         | steveharman wrote:
         | Surely anyone with any imagination inside Starlink would have
         | insisted on there being _42_ keys?
         | 
         | Perhaps Elon _doesn't_ have a brain the size of a planet after
         | all.
        
         | adolph wrote:
         | > So who does not have root access to "your" user terminal?
         | 
         | Not to defend this but curious: Unless the terminal is attached
         | to a local network that also has internet access, the satellite
         | network would need to be traversed in order to connect using
         | those keys, right? What kind of NAT/etc does Starlink use for
         | satellite routers?
        
           | 84634E1A607A wrote:
           | /56 DHCPv6 Prefix Delegation, and NAT44444 for IPv4
           | (192.168.1.x/24 for router, 192.168.100.x/24 for dish,
           | 100.64.x.x for CGNAT, 172.16.x.x for Ground Station inner
           | net, finally you are on the Internet).
        
         | doawoo wrote:
         | I'm really perplexed by this choice... at my current employer
         | we only deploy developer SSH keys to devices with DEV or QA
         | firmware. Prod images are signed and have SSH entirely
         | disabled.
         | 
         | We have a separate piece of software to remotely access devices
         | in prod to help diagnose engineering issues, where we can pull
         | up a REPL, but that's under access control and gated by devops
         | etc.
        
           | CSSer wrote:
           | This is deeply ironic to me because this company is run by
           | the same guy who has his underlings tearing through our
           | government data, secretly building repositories with titles
           | like NxGenBdoorExtract[0]. I don't trust this guy at all.
           | 
           | [0]https://www.npr.org/2025/04/15/nx-s1-5355896/doge-nlrb-
           | elon-...
        
         | walrus01 wrote:
         | If I would have to guess this is more mundane than it first
         | might appear, and probably a good security precaution. Rather
         | than pushing out one, two or three ssh key pairs that have the
         | private key pair running on some part of spacex CPE
         | provisioning infrastructure that has access to millions of
         | CPEs, they've got a more specific series of keys (perhaps by
         | serial number of terminal produced, or production date?) where
         | the management infrastructure has access to a much smaller
         | number of terminals. Whatever they're doing with the private
         | halves of those SSH keys can be compartmentalized.
        
       | nine_k wrote:
       | Dear author, please consider fixing the typo in the title, it
       | currently reads "Ternimal".
        
         | philipwhiuk wrote:
         | Classic keming issue.
        
           | jraph wrote:
           | Just classic letter inversion (the m and the n) :-)
        
       | breppp wrote:
       | > DARKNAVY built a basic QEMU-based emulation environment for the
       | Rev3 firmware
       | 
       | Anyone has links to resources about how to emulate a firmware
       | that connects to external devices (GPS here), any ready
       | solutions?
        
         | walterbell wrote:
         | https://android.googlesource.com/platform/external/qemu/+/2d...
         | 
         |  _> Android Emulator is downstream from the QEMU emulator. It
         | adds support for booting Android devices, emulates typical
         | Android hardware (OpenGL, GPS, GSM, Sensors) and a GUI
         | interface. The android emulator extends qemu in various ways._
        
       | purpleidea wrote:
       | Post the 41 public keys, we can see which devs use them probably.
        
       | alextousss wrote:
       | I'm interested in how to secure the firmware from reverse-
       | engineering in a product. Is there somewhere an introduction to
       | the techniques used by SpaceX there?
        
         | wepple wrote:
         | Step 1 is things like encrypted firmware, so I'd suspect SpaceX
         | does nothing or is reactive - they had debug pins until someone
         | published attacks utilizing them.
        
         | doawoo wrote:
         | At a minimum you'd want to encrypt your rootfs using secrets
         | that are hard to extract from secure elements. To go a step
         | further you can employ something like ARM's TrustZone to hide
         | away the sensitive operations (bootloader, decryptions, image
         | signing, etc.)
         | 
         | The fact that they could just dump the filesystem tells me
         | there's no protection employed at SpaceX aside from the boot
         | loader mentioned in the article.
        
         | drdaeman wrote:
         | As someone who used a bunch of good products with less than
         | great firmwares I would like you to ask to _please_ consider
         | _not_ doing this, unless you have a strong, real and well-
         | analyzed reason.
         | 
         | Rather, _please_ consider spending your resources wisely, on
         | something that benefits everyone and makes your product better.
         | For power users, a theoretical ability to modify your product
         | (possibly, in a ways you 've never even thought about) can be a
         | valuable benefit. So, unless you're certain to be seriously
         | harmed by this in some way, please consider not wasting your
         | (and your users') time on something of questionable value.
         | 
         | Just saying how it looks like from a technical end-user
         | perspective. I'm just really tired and even somewhat depressed
         | of having to hack my devices (lights, cat feeders, now a rowing
         | machine) to make them work properly.
        
       | numpad0 wrote:
       | Is this based on a shared code base with their rockets!? That's
       | cool!
        
         | antidumbass wrote:
         | No, it's based on OpenWRT.
        
         | axus wrote:
         | I'd say even cooler, it's a shared code-base with the
         | satellites; or maybe just a satellite simulator. Something that
         | has to send telemetry.
        
       | account-5 wrote:
       | How do you even get into doing this sort of thing? Reverse
       | engineering stuff is hard and all trolling is either really
       | expensive, or old and no longer developed; with a few exceptions,
       | I'm sure.
        
         | dfedbeef wrote:
         | Learn some hardware engineering first? Going to be hard to
         | reverse engineer things if you don't know what components do or
         | how to work with them.
        
         | immibis wrote:
         | First, you have to buy the thing. Second, take it apart. Third,
         | think of ways to break in. Fourth, actually do them. Fifth,
         | swear because you broke it.
         | 
         | Usually there's a UART. Apparently Starlink terminals don't
         | have a UART, so the guy took off the eMMC memory chip (which is
         | basically a soldered microSD card) instead.
        
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