SSH key exchange in mid-session

["Mark Riordan" <mriordan@xxxxxxxxxxxx>]

Does libssh support key exchange (KEX) in mid-session?

We observed a situation during the download of a huge file in which 
the session with our libssh-based client terminated abnormally 
after just about 1 GB (1073745534 bytes, including some proxy overhead).
Upon repeated attempts, the session terminated abnormally at the same
point each time.

The server in question identifies itself as "SSH-2.0-Internet Server SSHD".

We suspect that the remote server is initiating a key exchange after 1 GB,
but this is just a hunch at this point.

I looked at the libssh code and it seems to me that it does KEX
only at the beginning of a session.  But I could be missing something.

I have not been able to find mention of this in https://red.libssh.org/
or during my limited search of the mailing list archive at 
http://www.libssh.org/archive/ .
So, let me ask:  Is this a known limitation with libssh?

If not, I will proceed with turning on tracing (1 GB - ugghh)
to further investigate.

Thanks,

Mark
---------------------------------------------------------------
Mark Riordan
Sr Software Developer
T. 608.824.3632 | mriordan@xxxxxxxxxxxx
 
www.IpswitchFT.com