Subject: SFTP SSH_FXP_REALPATH packet question

From: "Nickolay L." <[email-masked]>
Date: Tue, 8 Nov 2005 18:36:10 +0200

Hello,

  In draft-ietf-secsh-filexfer-10.txt said, that packet has the
  following format :

  byte   SSH_FXP_REALPATH
  uint32 request-id
  string original-path [UTF-8]
  byte   control-byte [optional]
  string compose-path[0..n] [optional]

  So the question is : how do I logicaly-correct recognize, is the
  control-byte present, or absent? The way is to see the first byte
  after other fields, if it zero (It seems that compose-path will not
  be bigger than 2^24), the control-byte is absent. But this way not
  looks like the best..

  And another question, are there any available implementations of
  clients/server which supports versions 5 or/and 6 of SFTP protocol?

-- 
  Best regards,Nickolay mailto:<[email-masked]>

---

From: Joseph Galbraith <[email-masked]>
Date: Tue, 08 Nov 2005 10:06:32 -0700

>   be bigger than 2^24), the control-byte is absent. But this way not

Sorry that it isn't clear.  control-byte is _not_ optional
if compose-path is specified.

In other words, it is permissible to omit:

a.) both control-byte & compose-path
b.) compose-path only

It is not permissible to omit the control-byte if the compose-path
is present.

>   clients/server which supports versions 5 or/and 6 of SFTP protocol?

The WinSCP client supports v5.

VanDykes VShell server supports v5.

I don't know of any v6 implementations yet, though I know both
VanDyke's VShell and WinSCP do support some of the extensions
from v6.

Thanks,

Joseph

---

From: "Nickolay L." <[email-masked]>
Date: Tue, 8 Nov 2005 19:24:06 +0200

Hello Joseph,

JG> Sorry that it isn't clear.  control-byte is _not_ optional
JG> if compose-path is specified.

JG> In other words, it is permissible to omit:

JG> a.) both control-byte & compose-path
JG> b.) compose-path only

JG> It is not permissible to omit the control-byte if the compose-path
JG> is present.

Thank you for a quick answer.
I think, it would be useful to insert such note to draft?

---

From: Joseph Galbraith <[email-masked]>
Date: Tue, 08 Nov 2005 10:31:55 -0700

> I think, it would be useful to insert such note to draft?

Yes, I'll take care of this in the next round of editing.

Thanks,

Joseph