[syslinux] dynamic tftp content?

[H. Peter Anvin]

Craig wrote:
> Hi.
> 
> Has there ever been any consideration to allowing the tftp server to 
> provide dynamic content?
> 

Yes.  The protocol makes it difficult.

You pretty much have to guarantee that the contents is generated in a 
fraction of a second, or your client will most likely flood your server.

The problem is that in order to be able to answer a tsize query you have 
to know the full size of the output.  However, since TFTP isn't 
guaranteed to distinguish between an RRQ resend and a new request 
(pxelinux will make the distinction, but it's hard for the TFTP server 
to make use of it), so you have to have a reply before the first request.

I have a proposal for a TFTP "pause" option and opcode, but I would have 
to (a) implement it, and (b) write it up as an RFC, (c) figure out how 
to get it through IETF, which like to pretend TFTP doesn't exist.

	-hpa