PuTTY bug ssh-window-adjust

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From Peter Gutmann:

Actually this isn't so much a bug as (apparently) a conceptual error in the way
this is implemented.  The problem is that Putty (any version up to 0.53) waits
for a window adjust after everything it does past the initial handshake.  If my
server sends a SSH_MSG_CHANNEL_OPEN_CONFIRMATION advertising a window size
equal to my max packet size of 32K (heck, if I advertise a 4GB window), Putty
waits for a window adjust before reading anything.  Given that the window is
already at INT_MAX, I'm not sure how much more window it expects to get before
it can start.

The fact that it appears to work OK otherwise seems to be an artifact of
OpenSSH, which sends window adjusts like mad during a connection.  OTOH using
OpenSSH to connect to a server which just uses one big window isn't a problem,
while Putty can't get past the initial handshake talking to the same server.

<200210040834.UAA08658@ruru.cs.auckland.ac.nz>

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