openssh unix dev - Nov 2018 - [BUG?] sftp is echoing back prompt and commands in batch mode

Short description: All comands sent to server in batch mode are being
echoed back along with prompt.
Software Version: "OpenSSH_7.9p1, OpenSSL 1.1.1  11 Sep 2018" (as
printed by ssh -V)
Server and client systems: ArchLinux x86_64 fully updated as of 2018-11-02.

## How to reproduce

Provided that you have proper SSH key authentication in place, from
command line run:
echo "dir /var" | sftp -b - 0

## Expected output

/var/backups    /var/cache      /var/lib        /var/local      /var/lock
/var/log        /var/mail       /var/opt        /var/puppet     /var/run
/var/spool      /var/tmp        /var/www

## Actual output

sftp> dir /var
/var/backups    /var/cache      /var/lib        /var/local      /var/lock
/var/log        /var/mail       /var/opt        /var/puppet     /var/run
/var/spool      /var/tmp        /var/www

Please note the first line is the server prompt followed by the command echo.

## Workaround

Expunge the first line from the client output
echo "dir /var" | sftp -b - 0 | tail -n +2

## Notes
Batch mode is meant for script automation, not human operations, so
echoing the prompt and the commands doesn't make any sense and creates
problems while processing the output.
A possible solution that's also backward compatible with all scripts
using batch mode is to allow for a special prefix character to
commands to avoid any echoing, just like the "-" is used to avoid a
single failing command to terminate the client. Something like "@" or
"#" would be ok IMHO.

-- 
Vincenzo Romano - NotOrAnd.IT
Information Technologies
--
NON QVIETIS MARIBVS NAVTA PERITVS

If you truly intend this as a bug report, you should file it at
bugzilla.mindrot.org.

On Fri, Nov 02, 2018 at 12:25:22 +0100, Vincenzo Romano
wrote:
> Short description: All comands sent to server in batch mode are being
> echoed back along with prompt.
> Software Version: "OpenSSH_7.9p1, OpenSSL 1.1.1  11 Sep 2018" (as
> printed by ssh -V)
> Server and client systems: ArchLinux x86_64 fully updated as of 2018-11-02.
> 
> ## How to reproduce
> 
> Provided that you have proper SSH key authentication in place, from
> command line run:
> echo "dir /var" | sftp -b - 0
> 
> ## Expected output
> 
> /var/backups    /var/cache      /var/lib        /var/local      /var/lock
> /var/log        /var/mail       /var/opt        /var/puppet     /var/run
> /var/spool      /var/tmp        /var/www
> 
> ## Actual output
> 
> sftp> dir /var
> /var/backups    /var/cache      /var/lib        /var/local      /var/lock
> /var/log        /var/mail       /var/opt        /var/puppet     /var/run
> /var/spool      /var/tmp        /var/www
> 
> Please note the first line is the server prompt followed by the command
echo.
> 
> ## Workaround
> 
> Expunge the first line from the client output
> echo "dir /var" | sftp -b - 0 | tail -n +2
> 
> ## Notes
> Batch mode is meant for script automation, not human operations, so
> echoing the prompt and the commands doesn't make any sense and creates
> problems while processing the output.
> A possible solution that's also backward compatible with all scripts
> using batch mode is to allow for a special prefix character to
> commands to avoid any echoing, just like the "-" is used to avoid
a
> single failing command to terminate the client. Something like
"@" or
> "#" would be ok IMHO.
> 
> -- 
> Vincenzo Romano - NotOrAnd.IT
> Information Technologies
> --
> NON QVIETIS MARIBVS NAVTA PERITVS
> _______________________________________________
> openssh-unix-dev mailing list
> openssh-unix-dev at mindrot.org
> https://lists.mindrot.org/mailman/listinfo/openssh-unix-dev
-- 
Iain Morgan

Thanks, Iain.
I am willing to hear from other users whether anyone else sees this as a
bug before filing it.


--
Vincenzo Romano

Il giorno ven 2 nov 2018, 20:03 Iain Morgan <imorgan at nas.nasa.gov> ha
scritto:
> If you truly intend this as a bug report, you should file it at
> bugzilla.mindrot.org.
>
> On Fri, Nov 02, 2018 at 12:25:22 +0100, Vincenzo Romano wrote:
> > Short description: All comands sent to server in batch mode are being
> > echoed back along with prompt.
> > Software Version: "OpenSSH_7.9p1, OpenSSL 1.1.1  11 Sep
2018" (as
> > printed by ssh -V)
> > Server and client systems: ArchLinux x86_64 fully updated as of
> 2018-11-02.
> >
> > ## How to reproduce
> >
> > Provided that you have proper SSH key authentication in place, from
> > command line run:
> > echo "dir /var" | sftp -b - 0
> >
> > ## Expected output
> >
> > /var/backups    /var/cache      /var/lib        /var/local     
/var/lock
> > /var/log        /var/mail       /var/opt        /var/puppet    
/var/run
> > /var/spool      /var/tmp        /var/www
> >
> > ## Actual output
> >
> > sftp> dir /var
> > /var/backups    /var/cache      /var/lib        /var/local     
/var/lock
> > /var/log        /var/mail       /var/opt        /var/puppet    
/var/run
> > /var/spool      /var/tmp        /var/www
> >
> > Please note the first line is the server prompt followed by the
command
> echo.
> >
> > ## Workaround
> >
> > Expunge the first line from the client output
> > echo "dir /var" | sftp -b - 0 | tail -n +2
> >
> > ## Notes
> > Batch mode is meant for script automation, not human operations, so
> > echoing the prompt and the commands doesn't make any sense and
creates
> > problems while processing the output.
> > A possible solution that's also backward compatible with all
scripts
> > using batch mode is to allow for a special prefix character to
> > commands to avoid any echoing, just like the "-" is used to
avoid a
> > single failing command to terminate the client. Something like
"@" or
> > "#" would be ok IMHO.
> >
> > --
> > Vincenzo Romano - NotOrAnd.IT
> > Information Technologies
> > --
> > NON QVIETIS MARIBVS NAVTA PERITVS
> > _______________________________________________
> > openssh-unix-dev mailing list
> > openssh-unix-dev at mindrot.org
> > https://lists.mindrot.org/mailman/listinfo/openssh-unix-dev
>
> --
> Iain Morgan
>
Il giorno ven 2 nov 2018, 20:03 Iain Morgan <imorgan at nas.nasa.gov> ha
scritto:
> If you truly intend this as a bug report, you should file it at
> bugzilla.mindrot.org.
>
> On Fri, Nov 02, 2018 at 12:25:22 +0100, Vincenzo Romano wrote:
> > Short description: All comands sent to server in batch mode are being
> > echoed back along with prompt.
> > Software Version: "OpenSSH_7.9p1, OpenSSL 1.1.1  11 Sep
2018" (as
> > printed by ssh -V)
> > Server and client systems: ArchLinux x86_64 fully updated as of
> 2018-11-02.
> >
> > ## How to reproduce
> >
> > Provided that you have proper SSH key authentication in place, from
> > command line run:
> > echo "dir /var" | sftp -b - 0
> >
> > ## Expected output
> >
> > /var/backups    /var/cache      /var/lib        /var/local     
/var/lock
> > /var/log        /var/mail       /var/opt        /var/puppet    
/var/run
> > /var/spool      /var/tmp        /var/www
> >
> > ## Actual output
> >
> > sftp> dir /var
> > /var/backups    /var/cache      /var/lib        /var/local     
/var/lock
> > /var/log        /var/mail       /var/opt        /var/puppet    
/var/run
> > /var/spool      /var/tmp        /var/www
> >
> > Please note the first line is the server prompt followed by the
command
> echo.
> >
> > ## Workaround
> >
> > Expunge the first line from the client output
> > echo "dir /var" | sftp -b - 0 | tail -n +2
> >
> > ## Notes
> > Batch mode is meant for script automation, not human operations, so
> > echoing the prompt and the commands doesn't make any sense and
creates
> > problems while processing the output.
> > A possible solution that's also backward compatible with all
scripts
> > using batch mode is to allow for a special prefix character to
> > commands to avoid any echoing, just like the "-" is used to
avoid a
> > single failing command to terminate the client. Something like
"@" or
> > "#" would be ok IMHO.
> >
> > --
> > Vincenzo Romano - NotOrAnd.IT
> > Information Technologies
> > --
> > NON QVIETIS MARIBVS NAVTA PERITVS
> > _______________________________________________
> > openssh-unix-dev mailing list
> > openssh-unix-dev at mindrot.org
> > https://lists.mindrot.org/mailman/listinfo/openssh-unix-dev
>
> --
> Iain Morgan
>