rsync password prompt doesn't capture input and shows password in clear

rsync password prompt doesn't capture input and shows password in clear

[Marki]

Hello,

SSH password prompt captures the input correctly, and does not show it.

user@client /cygdrive/c/temp
$ ssh server
Password:
Password:

Rsync on the other hand won't even let me enter the password correctly.

user@client /cygdrive/c/temp
$ rsync -av xmppdb.db root@server:/tmp/
Password: 123
123
123
rsync error: received SIGINT, SIGTERM, or SIGHUP (code 20) at 
rsync.c(701) [sender=3.2.4dev]

user@client /cygdrive/c/temp
$ 123
-bash: 123: command not found

user@client /cygdrive/c/temp
$ 123
-bash: 123: command not found

user@client /cygdrive/c/temp
$ 123
-bash: 123: command not found

user@client /cygdrive/c/temp
$

Bye,
Marki

Re: rsync password prompt doesn't capture input and shows password in clear

[Andrey Repin]

Greetings, Marki!

> SSH password prompt captures the input correctly, and does not show it.

Unable to reproduce.

> user@client /cygdrive/c/temp
> $ ssh server
> Password:
> Password:

> Rsync on the other hand won't even let me enter the password correctly.

> user@client /cygdrive/c/temp
> $ rsync -av xmppdb.db root@server:/tmp/
> Password: 123
> 123
> 123
> rsync error: received SIGINT, SIGTERM, or SIGHUP (code 20) at 
> rsync.c(701) [sender=3.2.4dev]

$ rsync -av ./server.sgc $REMOTE:/home/x/
$USER@$REMOTE's password:
sending incremental file list
rsync: mkdir "/home/x" failed: Permission denied (13)
rsync error: error in file IO (code 11) at main.c(674) [Receiver=3.1.0]


> --

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-- 
With best regards,
Andrey Repin
Wednesday, March 10, 2021 23:55:06

Sorry for my terrible english...

Re: rsync password prompt doesn't capture input and shows password in clear

[Marki]

On March 10, 2021 9:58:14 PM GMT+01:00, Andrey Repin 
<anrdaemon@yandex.ru> wrote:
>Greetings, Marki!
>
>> SSH password prompt captures the input correctly, and does not show
>it.
>
>Unable to reproduce.

Unable to reproduce that SSH works as expected? Well, that's not good.

Anyway. I'll get back to you with the guides you provided.

Thanks.
Marki

Re: rsync password prompt doesn't capture input and shows password in clear

[Andrey Repin]

Greetings, Marki!

> On March 10, 2021 9:58:14 PM GMT+01:00, Andrey Repin 

>>Greetings, Marki!
>>
>>> SSH password prompt captures the input correctly, and does not show
>>it.
>>
>>Unable to reproduce.

> Unable to reproduce that SSH works as expected? Well, that's not good.

wat…

You blamed rsync, I displayed that it works as expected.

> Anyway. I'll get back to you with the guides you provided.

Please don't quote cleartext emails. We do not endorse spam bots harvesting
addresses.


-- 
With best regards,
Andrey Repin
Thursday, March 11, 2021 1:52:31

Sorry for my terrible english...

Re: rsync password prompt doesn't capture input and shows password in clear

[Marki]

Hello,

First, I showed that SSH password prompt works as expected: you can 
input the password such that SSH client can process it, and it will not 
be echoed to the command prompt.

You claimed that you could not reproduce!? While that was the expected 
outcome for SSH. (It is working correctly)

Only then I showed that the same is not true for rsync. When I input a 
password, it will get echoed and also rsync will not process it, since 
standard input somehow goes elsewhere.

I am working on why rsync would behave like that on my end.

Thanks.

Re: rsync password prompt doesn't capture input and shows password in clear

[David Dombrowsky]

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On 3/10/21 6:20 PM, Marki wrote:
> Only then I showed that the same is not true for rsync. When I input a
> password, it will get echoed and also rsync will not process it, since
> standard input somehow goes elsewhere.

If I had to guess, it's probably the same as the problems I was seeing
with gpg-agent not being able to capture the tty correctly to prompt for
the password.  I never had a problem with the ssh agent though.

Unfortunately I do not have a good solution for it, as it seems to
happen only to some people some time on some systems.  After fighting
with it for an afternoon, I simply wrote a pinentry program with my
password hardcoded into it.  Yay for security.

The hack is here for reference (DO NOT USE ON PUBLIC PRODUCTION
MACHINES!) -> https://x.cygwin.com/ml/cygwin/2019-01/msg00178.html

I recheck the stock program every few months, and this problem still exists.

-- 
David Dombrowsky | Chief Software Engineer
6th Street Radio LLC | 6thstreetradio.org | 518-374-3204
https://www.linkedin.com/in/david-dombrowsky-94334415
VHVlIE1hciAgOSAwMjoxMzowMiBFU1QgMjAyMQo=


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 473 bytes --]

Re: rsync password prompt doesn't capture input and shows password in clear

[Corinna Vinschen]

On Mar 10 19:11, Marki wrote:
> Hello,
> 
> SSH password prompt captures the input correctly, and does not show it.
> 
> user@client /cygdrive/c/temp
> $ ssh server
> Password:
> Password:
> 
> Rsync on the other hand won't even let me enter the password correctly.
> 
> user@client /cygdrive/c/temp
> $ rsync -av xmppdb.db root@server:/tmp/
> Password: 123
> 123
> 123
> rsync error: received SIGINT, SIGTERM, or SIGHUP (code 20) at rsync.c(701)
> [sender=3.2.4dev]

I tried this myself in mintty as well as in a Console window, and in
both cases the password was not echoed and taken correctly:

  $ rsync -av x.exe user@remote:/tmp/
  Password:
  sending incremental file list
  x.exe
  [...]

Are you sure you're using the Cygwin rsync?


Corinna

Re: rsync password prompt doesn't capture input and shows password in clear

[Andrey Repin]

Greetings, Corinna Vinschen via Cygwin!

> On Mar 10 19:11, Marki wrote:
>> Hello,
>> 
>> SSH password prompt captures the input correctly, and does not show it.
>> 
>> user@client /cygdrive/c/temp
>> $ ssh server
>> Password:
>> Password:
>> 
>> Rsync on the other hand won't even let me enter the password correctly.
>> 
>> user@client /cygdrive/c/temp
>> $ rsync -av xmppdb.db root@server:/tmp/
>> Password: 123
>> 123
>> 123
>> rsync error: received SIGINT, SIGTERM, or SIGHUP (code 20) at rsync.c(701)
>> [sender=3.2.4dev]

> I tried this myself in mintty as well as in a Console window, and in
> both cases the password was not echoed and taken correctly:

>   $ rsync -av x.exe user@remote:/tmp/
>   Password:
>   sending incremental file list
>   x.exe
>   [...]

> Are you sure you're using the Cygwin rsync?

-rsync
+ssh

There's no MS-provided rsync, but there's ssh in C:\Windows\System32\OpenSSH\


-- 
With best regards,
Andrey Repin
Thursday, March 11, 2021 13:40:03

Sorry for my terrible english...

Re: rsync password prompt doesn't capture input and shows password in clear

[Corinna Vinschen]

On Mar 11 13:42, Andrey Repin wrote:
> Greetings, Corinna Vinschen via Cygwin!
> 
> > On Mar 10 19:11, Marki wrote:
> >> Hello,
> >> 
> >> SSH password prompt captures the input correctly, and does not show it.
> >> 
> >> user@client /cygdrive/c/temp
> >> $ ssh server
> >> Password:
> >> Password:
> >> 
> >> Rsync on the other hand won't even let me enter the password correctly.
> >> 
> >> user@client /cygdrive/c/temp
> >> $ rsync -av xmppdb.db root@server:/tmp/
> >> Password: 123
> >> 123
> >> 123
> >> rsync error: received SIGINT, SIGTERM, or SIGHUP (code 20) at rsync.c(701)
> >> [sender=3.2.4dev]
> 
> > I tried this myself in mintty as well as in a Console window, and in
> > both cases the password was not echoed and taken correctly:
> 
> >   $ rsync -av x.exe user@remote:/tmp/
> >   Password:
> >   sending incremental file list
> >   x.exe
> >   [...]
> 
> > Are you sure you're using the Cygwin rsync?
> 
> -rsync
> +ssh
> 
> There's no MS-provided rsync, but there's ssh in C:\Windows\System32\OpenSSH\

If that ssh is first in $PATH, then that's the potential problem.


Corinna

Re: rsync password prompt doesn't capture input and shows password in clear

[Takashi Yano]

On Thu, 11 Mar 2021 13:38:58 +0100
Corinna Vinschen wrote:
> On Mar 11 13:42, Andrey Repin wrote:
> > Greetings, Corinna Vinschen via Cygwin!
> > 
> > > On Mar 10 19:11, Marki wrote:
> > >> Hello,
> > >> 
> > >> SSH password prompt captures the input correctly, and does not show it.
> > >> 
> > >> user@client /cygdrive/c/temp
> > >> $ ssh server
> > >> Password:
> > >> Password:
> > >> 
> > >> Rsync on the other hand won't even let me enter the password correctly.
> > >> 
> > >> user@client /cygdrive/c/temp
> > >> $ rsync -av xmppdb.db root@server:/tmp/
> > >> Password: 123
> > >> 123
> > >> 123
> > >> rsync error: received SIGINT, SIGTERM, or SIGHUP (code 20) at rsync.c(701)
> > >> [sender=3.2.4dev]
> > 
> > > I tried this myself in mintty as well as in a Console window, and in
> > > both cases the password was not echoed and taken correctly:
> > 
> > >   $ rsync -av x.exe user@remote:/tmp/
> > >   Password:
> > >   sending incremental file list
> > >   x.exe
> > >   [...]
> > 
> > > Are you sure you're using the Cygwin rsync?
> > 
> > -rsync
> > +ssh
> > 
> > There's no MS-provided rsync, but there's ssh in C:\Windows\System32\OpenSSH\
> 
> If that ssh is first in $PATH, then that's the potential problem.

That seems to be the cause. I can reproduce the issue by:

env PATH="/cygdrive/c/Windows/system32/OpenSSH:$PATH" rsync -av somefile user@server:/tmp

in mintty with 64bit cygwin.

-- 
Takashi Yano <takashi.yano@nifty.ne.jp>