Net::SSH::Perl

Hi all,

Below is my script that will be used to connect to a remote host and
change my password automatically:

===========================================
#!/usr/bin/perl


use strict();
use Net::SSH::Perl;


$user="jaws";
$pass="password";
$host="xxx.xxx.xxx.xxx";
$old_password="password";
$new_password="newpass";


my $ssh = Net::SSH::Perl->new($host,debug=>1,use_pty=>1);
$ssh->login($user, $pass);


$ssh->register_handler("stderr", sub {
my($channel, $buffer) = @_;
my $str = $buffer->bytes;


if ($str eq "Enter login password: ") {
$channel->send_data($old_password);
}


elsif ($str eq "New password: ") {
$channel->send_data($new_password);
}

elsif ($str eq "Re-enter new password: ") {
$channel->send_data($new_password);
}
});
$ssh->cmd('passwd');
==========================================

After running the program, my password didnt changed I was still able to
connect using the old password.

Does anybody has an idea what's missing or wrong with my script?

Thanks.

Jaws

Sorry, I cant comment on the perl as yet but, are you not in the least bit
worried that someone might hack into your base system - get the unencrypted
password (old password) then log on - using ssh to the other box ?

ssh is not 100% flawless

From a security point of view it is a nightmare, from a SA point of view - I
can see where you are coming from !

Just curious is all
"blob" <jaws@skyinet.net> wrote in message news:3f57f2ae@news.skyinet.net...[color=blue]
> Hi all,
>
> Below is my script that will be used to connect to a remote host and
> change my password automatically:
>
> ===========================================
> #!/usr/bin/perl
>
>
> use strict();
> use Net::SSH::Perl;
>
>
> $user="jaws";
> $pass="password";
> $host="xxx.xxx.xxx.xxx";
> $old_password="password";
> $new_password="newpass";
>
>
> my $ssh = Net::SSH::Perl->new($host,debug=>1,use_pty=>1);
> $ssh->login($user, $pass);
>
>
> $ssh->register_handler("stderr", sub {
> my($channel, $buffer) = @_;
> my $str = $buffer->bytes;
>
>
> if ($str eq "Enter login password: ") {
> $channel->send_data($old_password);
> }
>
>
> elsif ($str eq "New password: ") {
> $channel->send_data($new_password);
> }
>
> elsif ($str eq "Re-enter new password: ") {
> $channel->send_data($new_password);
> }
> });
> $ssh->cmd('passwd');
> ==========================================
>
> After running the program, my password didnt changed I was still able to
> connect using the old password.
>
> Does anybody has an idea what's missing or wrong with my script?
>
> Thanks.
>
> Jaws
>[/color]

On Fri, 05 Sep 2003 10:07:49 -0800
blob <jaws@skyinet.net> wrote:[color=blue]
> Hi all,
>
> Below is my script that will be used to connect to a remote host and
>
> change my password automatically:[/color]
<sniped for brevity>[color=blue]
>
> After running the program, my password didnt changed I was still
> able to connect using the old password.
>
> Does anybody has an idea what's missing or wrong with my script?[/color]

Just a suggestion - you may wish to use one of the Expect modules for
what you're doing. Expect is, IMHO, better suited for this task. And
in true Perl fashion, there is a module to interact with Expect :)

HTH

--
Jim

Copyright notice: all code written by the author in this post is
released under the GPL. http://www.gnu.org/licenses/gpl.txt
for more information.

a fortune quote ...
Hlade's Law: If you have a difficult task, give it to a lazy
person -- they will find an easier way to do it.

On Fri, 05 Sep 2003 10:07:49 -0800, blob wrote:
[color=blue]
> Hi all,
>
> Below is my script that will be used to connect to a remote host and
> change my password automatically:
>
> ===========================================
> #!/usr/bin/perl
>
>
> use strict();
> use Net::SSH::Perl;
>
>
> $user="jaws";
> $pass="password";
> $host="xxx.xxx.xxx.xxx";
> $old_password="password";
> $new_password="newpass";
>
>
> my $ssh = Net::SSH::Perl->new($host,debug=>1,use_pty=>1);
> $ssh->login($user, $pass);
>
>
> $ssh->register_handler("stderr", sub {
> my($channel, $buffer) = @_;
> my $str = $buffer->bytes;
>
>
> if ($str eq "Enter login password: ") {
> $channel->send_data($old_password);
> }
>
>
> elsif ($str eq "New password: ") {
> $channel->send_data($new_password);
> }
>
> elsif ($str eq "Re-enter new password: ") {
> $channel->send_data($new_password);
> }
> });
> $ssh->cmd('passwd');
> ==========================================
>
> After running the program, my password didnt changed I was still able to
> connect using the old password.
>
> Does anybody has an idea what's missing or wrong with my script?
>
> Thanks.
>
> Jaws[/color]

Instead of waiting for the exact string, why not use regular expresions,
which might eliminate typo's. Something like:

if ($str =~ /enter\s+login\s+password/i ) {
$channel->send_data($old_password);
}


elsif ($str =~ /new\s+password/i ) {
$channel->send_data($new_password);
}

elsif ($str =~ /re.enter\s+new\s+password/i ) {
$channel->send_data($new_password);
}

Cheers

--
Nico Coetzee

http://www.itfirms.co.za/
http://za.pm.org/
http://forums.databasejournal.com/

To the systems programmer, users and applications serve only to provide a
test load.