4 ms·

Now if only there were a PCI ADSL2+ modem that was a real network interface and not another crappy, exploitable, buffer bloat infested, traffic intercepting ces

by nullc 12y ago

Now if only there were a PCI ADSL2+ modem that was a real network interface and not another crappy, exploitable, buffer bloat infested, traffic intercepting cesspool (but embedded on a PCI card)...

mindslight 12y ago
Any DSL modem is going to be a proprietary cesspool of who knows what - putting that on a trusted PCI bus seems like the exact wrong thing to do. I was just looking into ADSL2+ routers supported by OpenWRT and concluded it wasn't worth the bother. Just get any old proprietary ADSL2+ modem, set it to bridge mode, and treat its ethernet as the actual demarc point. Better galvanic isolation, too.
- nullc 12y ago
  One problem there is that you lose all queue management and it seems they all do awful things. Many of them also randomly intercept and tamper with tcp connections even while not natting.
  - mindslight 12y ago
    Yes, it's less than ideal. But I don't think you're ever going to find a nice, proper, trustable device. Communications gear is basically just complex software (DSP and the like). The parts count will be minimized to keep costs down, so the necessarily-proprietary parts get mingled with the needlessly-proprietary ones. Redeveloping those blobs as free software is certainly possible, but it will always lag behind the proprietary version. IMHO, that effort is better spent on working around the brokenness of such devices - maintain your own txqueue at a slightly slower rate than the modem, etc. (My thinking on the "ideal cellphone" is the same - physically separate the baseband from the personal computer, with an IP-only interface (eg Wifi) between them.) FWIW, I haven't noticed any packet mangling from my ADSL2+ modem in bridge mode, but I haven't looked very hard either.
    - walterbell 12y ago
      > physically separate the baseband from the personal computer, with an IP-only interface (eg Wifi) between them Are there any options on the market besides iPod Touch and Samsung Galaxy S WiFi?
      - mindslight 12y ago
        Eh? Any laptop or wifi-only tablet would do, so I don't see why you're implying there's a shortage? I've been meaning to enumerate the possibilities of things with long battery life that will ideally run normal GNU/Linux with a chorded keyboard for input. If that works out successfully, then a smart watch for notifications would be the logical next step.
        walterbell 12y ago
        Since you mentioned "ideal cellphone", I was thinking of pocketable devices (< 5"), not many of those around which are baseband-free.
        mindslight 12y ago
        Ah sorry, good point. I had other requirements in mind that made me think I would end up with a larger device (battery life, un-tablety to hopefully run GNU as a base), and forgot about those when writing my comment. Not that I really want something that won't fit in my pocket, so thanks for your suggestions of things to look into :> Although a device with a baseband (but antenna removed) could even be a decent starting point. Lacking a network channel, it would be basically equivalent security to a desktop CPU (that's an uncomfortable truth).
        walterbell 12y ago
        Thanks for pointer on antenna removal, will search for teardown examples of successful removal. Could be added to a future version of guides similar to https://blog.torproject.org/blog/mission-impossible-hardening-android-security-and-privacy https://blog.torproject.org/blog/mission-impossible-hardenin...
pktgen 12y ago
Agreed. For now you can use bridge mode and rate limit on your router (to counter the ridiculous buffer on the modem).
martinml 12y ago
Something like this? http://linitx.com/product/adsl2-pci-card-single-port-adsl-modem-annex-a/12181 http://linitx.com/product/adsl2-pci-card-single-port-adsl-mo...
- nullc 12y ago
  Nope, thats actually an ADSL router with its own operating system which just presents an ethernet interface to the host. Maybe it's better than typical consumer routers. But I'd bet it still does awful queuing stuff that you cannot control.
  - martinml 12y ago
    Hm, are you sure? It has a jumper to change it to "PCI" instead of "LAN", which I guess would expose directly a PPP interface, but I can't seem to find any documentation on that feature. Edit: well, you were right. It seems to be a full blown Linux-based router, just with a weird form factor: http://tjworld.net/wiki/Linux/Embedded/Infineon/Danube/ADSL2PCI http://tjworld.net/wiki/Linux/Embedded/Infineon/Danube/ADSL2...

by nullc 12y ago

Now if only there were a PCI ADSL2+ modem that was a real network interface and not another crappy, exploitable, buffer bloat infested, traffic intercepting cesspool (but embedded on a PCI card)...

mindslight 12y ago

Any DSL modem is going to be a proprietary cesspool of who knows what - putting that on a trusted PCI bus seems like the exact wrong thing to do. I was just looking into ADSL2+ routers supported by OpenWRT and concluded it wasn't worth the bother. Just get any old proprietary ADSL2+ modem, set it to bridge mode, and treat its ethernet as the actual demarc point. Better galvanic isolation, too.

nullc 12y ago
One problem there is that you lose all queue management and it seems they all do awful things. Many of them also randomly intercept and tamper with tcp connections even while not natting.
- mindslight 12y ago
  Yes, it's less than ideal. But I don't think you're ever going to find a nice, proper, trustable device. Communications gear is basically just complex software (DSP and the like). The parts count will be minimized to keep costs down, so the necessarily-proprietary parts get mingled with the needlessly-proprietary ones. Redeveloping those blobs as free software is certainly possible, but it will always lag behind the proprietary version. IMHO, that effort is better spent on working around the brokenness of such devices - maintain your own txqueue at a slightly slower rate than the modem, etc. (My thinking on the "ideal cellphone" is the same - physically separate the baseband from the personal computer, with an IP-only interface (eg Wifi) between them.) FWIW, I haven't noticed any packet mangling from my ADSL2+ modem in bridge mode, but I haven't looked very hard either.
  - walterbell 12y ago
    > physically separate the baseband from the personal computer, with an IP-only interface (eg Wifi) between them Are there any options on the market besides iPod Touch and Samsung Galaxy S WiFi?
    - mindslight 12y ago
      Eh? Any laptop or wifi-only tablet would do, so I don't see why you're implying there's a shortage? I've been meaning to enumerate the possibilities of things with long battery life that will ideally run normal GNU/Linux with a chorded keyboard for input. If that works out successfully, then a smart watch for notifications would be the logical next step.
      - walterbell 12y ago
        Since you mentioned "ideal cellphone", I was thinking of pocketable devices (< 5"), not many of those around which are baseband-free.
        mindslight 12y ago
        Ah sorry, good point. I had other requirements in mind that made me think I would end up with a larger device (battery life, un-tablety to hopefully run GNU as a base), and forgot about those when writing my comment. Not that I really want something that won't fit in my pocket, so thanks for your suggestions of things to look into :> Although a device with a baseband (but antenna removed) could even be a decent starting point. Lacking a network channel, it would be basically equivalent security to a desktop CPU (that's an uncomfortable truth).
        walterbell 12y ago
        Thanks for pointer on antenna removal, will search for teardown examples of successful removal. Could be added to a future version of guides similar to https://blog.torproject.org/blog/mission-impossible-hardening-android-security-and-privacy https://blog.torproject.org/blog/mission-impossible-hardenin...

pktgen 12y ago

Agreed. For now you can use bridge mode and rate limit on your router (to counter the ridiculous buffer on the modem).

martinml 12y ago

Something like this? http://linitx.com/product/adsl2-pci-card-single-port-adsl-modem-annex-a/12181 http://linitx.com/product/adsl2-pci-card-single-port-adsl-mo...

nullc 12y ago
Nope, thats actually an ADSL router with its own operating system which just presents an ethernet interface to the host. Maybe it's better than typical consumer routers. But I'd bet it still does awful queuing stuff that you cannot control.
- martinml 12y ago
  Hm, are you sure? It has a jumper to change it to "PCI" instead of "LAN", which I guess would expose directly a PPP interface, but I can't seem to find any documentation on that feature. Edit: well, you were right. It seems to be a full blown Linux-based router, just with a weird form factor: http://tjworld.net/wiki/Linux/Embedded/Infineon/Danube/ADSL2PCI http://tjworld.net/wiki/Linux/Embedded/Infineon/Danube/ADSL2...