Re^2: Using SSH and SCP in a perl script with taint flag

Hi Salva, thanks for your reply. I've read through the documentation for OpenSSH and it seems like a much better method than my current attempts. I'm getting really confused though with the examples in the documentation, and my own attempts aren't going well. Would you be able to help further? My current code sample is below.

#!/usr/bin/perl -wT

use Net::OpenSSH;
$ENV{PATH} = "/bin";
my $ssh = Net::OpenSSH->new("<IP>", user => "<username>", password => 
+"<password>");
$ssh->error and die "Can't ssh to host: " . $ssh->error;
$ssh->system('whoami')or die "whoami failed: " .$ssh->error;
[download]

I should say, I have tried this without the password bit (as I use private key authentication) as well, and I have tried using syntax such as my $ssh = Net::OpenSSH->new("<user>\@<Host IP>");.
I get the following error:

Can't exec "ssh": No such file or directory at /usr/share/perl5/Net/Op
+enSSH.pm line 731.
Can't ssh to host: unable to establish master SSH connection: master p
+rocess exited unexpectedly
[download]

Do you have any further advice?
Thanks very much again! Really appreciate your help.

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Re^3: Using SSH and SCP in a perl script with taint flag by salva (Canon) on May 29, 2015 at 11:01 UTC
The problem is that the OpenSSH client `ssh` is not in the scrawny path you are using. Try adding `/usr/bin` too: `$ENV{PATH} = "/bin:/usr/bin";` [download]	[reply] [d/l] [select]
Re^4: Using SSH and SCP in a perl script with taint flag by stefl (Acolyte) on May 29, 2015 at 14:20 UTC
Thanks very much salva, your advice was brilliant. Got it working now, you've saved me days of frustration! For anyone else in my situation who is new to this stuff, I fixed this by adding the ctl_dir option: `my $ssh = Net::OpenSSH->new($host, user=>$user, ctl_dir=>$ctldir);`. I created the $ctldir (called .libnet-openssh-perl) within my /var/www directory and ensured the owner was www-data. I hope this can help someone else too! Thanks again salva, legend!	[reply] [d/l]
Re^4: Using SSH and SCP in a perl script with taint flag by stefl (Acolyte) on May 29, 2015 at 13:31 UTC
Genius! Thanks very much! Is there anything special I need to do to get this to work when running the script as www-data? On the command line (to emulate running the webform) I run it as follows: `sudo -u www-data perl -T test` but get an error message: `Can't ssh to host: unable to create ctl_dir /var/www/.libnet-openssh-perl` This might be more of a general Linux question, in which case I apologise. I am able to ssh as the www-data outwith the perl script though, so I don't know what is wrong. Thanks very much for your advice, you seem to know a lot about using this module and I'm very, very new to this sort of thing.	[reply] [d/l] [select]
Re^5: Using SSH and SCP in a perl script with taint flag by salva (Canon) on May 29, 2015 at 13:54 UTC
The module is trying to create the directory `/var/www/.libnet-openssh-perl` but it can't. It needs it to place a UNIX socket there for communication with the OpenSSH client. The module documentation has a TROUBLESHOOTING section that discusses most of the issues you can encounter in detail. You should read it. But in any case, fell free to ask here again if that doesn't solve your problems. you seem to know a lot about using this module Hey, I should! I wrote it!	[reply] [d/l]


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