• SSH testing

    From StackFault@21:1/172 to All on Wed Nov 7 04:20:25 2018
    Hi,

    I've been testing the SSH server and came to some interesting conclusions and will post here for some reference.

    When connecting from the latest OpenSSH client (ie running Arch Linux for example) you have to use: ssh -l user host -p port -c aes256-cbc

    Older clients still supports aes256-cbc as part of their base
    ciphers configuration so no need to specify.

    I noticed that when you connect via SSH and there is no NAT in the network path, the session opens directly.

    If there is a NAT device, the behavior is a little bit different.

    1, After authentication, the session sits there without displaying anything
    and you get disconnected after a couple of seconds.
    2, After authentication, when the session sits you press any key, the node comes up and you can use it normally.

    This is interesting and I would like to know if anyone have similar observations.

    Thnaks,


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  • From eggy@21:4/143 to All on Thu Nov 8 01:10:03 2018
    On 11/06/18, StackFault said the following...

    When connecting from the latest OpenSSH client (ie running Arch Linux for example) you have to use: ssh -l user host -p port -c aes256-cbc
    Older clients still supports aes256-cbc as part of their base
    ciphers configuration so no need to specify.
    I noticed the same thing when I tried to SSH from one of my more recent Linux systems, it complained about ciphers when I tried to connect. I hadn't dug
    into it, but this explains what was happening at least.

    If there is a NAT device, the behavior is a little bit different.

    1, After authentication, the session sits there without displaying anything and you get disconnected after a couple of seconds.
    2, After authentication, when the session sits you press any key, the
    node comes up and you can use it normally.
    I've observed the same behavior on this side while using NAT with SSH. I was about to post a question asking about SSH when I ran across this reporting the same issue I noticed.

    Thanks,
    Eggy

    --- Mystic BBS v1.12 A39 2018/04/21 (Linux/64)
    * Origin: Eggy BBS (21:4/143)
  • From eggy@21:4/143 to All on Fri Nov 9 02:08:24 2018
    On 11/07/18, eggy said the following...
    I've observed the same behavior on this side while using NAT with SSH. I was about to post a question asking about SSH when I ran across this reporting the same issue I noticed.

    To follow up on this thread some more.. after testing with a couple random volunteers from the EFNet IRC channel, we have confirmed SSH is working
    through NAT when using SyncTERM. It doesn't seem to work to well with anything else. I tested with putty on windows, I haven't tried from an external Linux system.

    Thanks,
    Eggy

    --- Mystic BBS v1.12 A39 2018/04/21 (Linux/64)
    * Origin: Eggy BBS (21:4/143)
  • From StackFault@21:1/172 to eggy on Fri Nov 9 12:23:58 2018
    On 11/07/18, eggy said the following...
    I've observed the same behavior on this side while using NAT with SSH was about to post a question asking about SSH when I ran across this reporting the same issue I noticed.

    To follow up on this thread some more.. after testing with a couple
    random volunteers from the EFNet IRC channel, we have confirmed SSH is working through NAT when using SyncTERM. It doesn't seem to work to well with anything else. I tested with putty on windows, I haven't tried from an external Linux system.

    Exact same thing here.
    Tried disabling CP and charset auto-detect, same thing again.

    Too bad we can't display an SSH banner at that point, we could print to press escape twice, in memories of good old FrontDoor days :)

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    * Origin: The Bottomless Abyss BBS (21:1/172)