[ptxdist] dropbear and sftp-server mismatch

[ptxdist] dropbear and sftp-server mismatch

[Ian Abbott]

Hi there,

Since scp now defaults to using the SFTP protocol which is not built in 
to dropbear, I thought I'd configure my platform to enable 
OPENSSH_SFTP_SERVER, but I ran into a 'gotcha'.  The server gets 
installed as "/usr/sbin/sftp-server" (and `--libexecdir` is configured 
as "/usr/sbin"), but dropbear looks for it at "/usr/libexec/sftp-server".

The path to the sftp-server can be set in dropbear by defining the 
`SFTPSERVER_PATH` macro in "localoptions.h" file (constructed by 
"rules/dropbear.make").  That is not currently done, but is easy enough 
to add.  I was wondering whether it should be made configurable by a new 
option in "rules/dropbear.in" or not (using "/usr/sbin/sftp-server" as 
the default value).

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Re: [ptxdist] dropbear and sftp-server mismatch

[Alexander Dahl]

Hello Ian,

Am Thu, Apr 28, 2022 at 07:23:09PM +0100 schrieb Ian Abbott:
> Hi there,
> 
> Since scp now defaults to using the SFTP protocol which is not built in to
> dropbear, I thought I'd configure my platform to enable OPENSSH_SFTP_SERVER,
> but I ran into a 'gotcha'.  The server gets installed as
> "/usr/sbin/sftp-server" (and `--libexecdir` is configured as "/usr/sbin"),

This happens in the OpenSSH package, where libexecdir is configured as
/usr/sbin since 2003 … wow.

> but dropbear looks for it at "/usr/libexec/sftp-server".

Yes.

> The path to the sftp-server can be set in dropbear by defining the
> `SFTPSERVER_PATH` macro in "localoptions.h" file (constructed by
> "rules/dropbear.make").  That is not currently done, but is easy enough to
> add.  I was wondering whether it should be made configurable by a new option
> in "rules/dropbear.in" or not (using "/usr/sbin/sftp-server" as the default
> value).

I would tend to hardcode it into rules/dropbear.make … I don't see a
reason to have that as configurable menu option, do you?  Because we
probably won't change the path in openssh package, and to my knowledge
there's no alternative to the one from openssh?

Care to send a patch?

Greets
Alex

Re: [ptxdist] dropbear and sftp-server mismatch

[Michael Olbrich]

Hi,

On Fri, Apr 29, 2022 at 07:33:14AM +0200, Alexander Dahl wrote:
> Am Thu, Apr 28, 2022 at 07:23:09PM +0100 schrieb Ian Abbott:
> > Hi there,
> > 
> > Since scp now defaults to using the SFTP protocol which is not built in to
> > dropbear, I thought I'd configure my platform to enable OPENSSH_SFTP_SERVER,
> > but I ran into a 'gotcha'.  The server gets installed as
> > "/usr/sbin/sftp-server" (and `--libexecdir` is configured as "/usr/sbin"),
> 
> This happens in the OpenSSH package, where libexecdir is configured as
> /usr/sbin since 2003 … wow.
> 
> > but dropbear looks for it at "/usr/libexec/sftp-server".
> 
> Yes.
> 
> > The path to the sftp-server can be set in dropbear by defining the
> > `SFTPSERVER_PATH` macro in "localoptions.h" file (constructed by
> > "rules/dropbear.make").  That is not currently done, but is easy enough to
> > add.  I was wondering whether it should be made configurable by a new option
> > in "rules/dropbear.in" or not (using "/usr/sbin/sftp-server" as the default
> > value).
> 
> I would tend to hardcode it into rules/dropbear.make … I don't see a
> reason to have that as configurable menu option, do you?  Because we
> probably won't change the path in openssh package, and to my knowledge
> there's no alternative to the one from openssh?

I agree. No need for an option.

> Care to send a patch?

That would be great.

Michael


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