Re: Channel close logic, needs clarification?

[Tatu Ylonen <ylo%ssh.com@localhost>]

> On Sun, Mar 11, 2001 at 10:41:00PM +0200, Tatu Ylonen wrote:
> > It is legal to send other messages, e.g. channel requests, after both
> > sending and receing EOF.
> 
> Is it legal to send SSH_MSG_CHANNEL_EXTENDED_DATA after a EOF is
> sent?  I asume that the EOF refers to both SSH_MSG_CHANNEL_DATA and
> SSH_MSG_CHANNEL_EXTENDED_DATA.

I actually never thought about this.

I think it should be legal, since extended data is used for things like
stderr.

> > > The OpenSSH server does not wait for the EOF message from the client.
> > > However, since the servers' child process is dead, the server decides
> > > that it will not write to more data to the 'stdin' handle and does _not_
> > > wait for the EOF message from the client.  This way the the channel is
> > > correctly closed.
> > 
> > It is legal to send SSH_MSG_CHANNEL_CLOSE before receiving/sending EOF
> 
> I think this is a typo. Is it really legal to send
> a SSH_MSG_CHANNEL_CLOSE before a SSH_MSG_CHANNEL_EOF is sent?

To be more accurate, it is legal to send SSH_MSG_CHANNEL_CLOSE without
sending SSH_MSG_CHANNEL_EOF.  A party MUST NOT send
anything to the channel after it has sent SSH_MSG_CHANNEL_CLOSE.

    Tatu

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