Automating SSH public key pushes with Perl

Automating SSH public key pushes to servers.

The code below uses Expect and SSH to create & permission the .ssh directory. Followed by SSH copying the local temp file as the authorized_keys file to the .ssh subdir on the target server .

Be sure to set StrictHostKeyChecking=no in the SSH client side config.

---

#!/usr/bin/perl

use strict;
use warnings;
use English;
use Expect;
use Net::Ping;

my $username = "USER";
my $password = "PASS";
my $homedir  = "\/export\/home\/$username";
my $ssh_dir  = "$homedir\/.ssh";
my $ssh_pub  = "
ssh-dss BLAH BLAH use your own public key file entry here.
";

if ( ! $ARGV[0] ) {
        print "$0  \n";
        exit
} 

my $host = "$ARGV[0]";
my $p 	 = Net::Ping->new();
if ( $p->ping($host) ) {
	print "Deploying public key to $host \n";
	create_ssh_dir();
	chmod_ssh_dir();
	push_ssh_key();
} else {
	print "Seems $host is not reachable \n";
}
$p->close();

sub create_ssh_dir {
my $ssh_cmd  = "/usr/bin/ssh $username\@$host 'mkdir $ssh_dir'";

my $timeout  = '5';
my $exp      = Expect->spawn($ssh_cmd) or die "Cannot spawn ssh command \n";
$exp->expect($timeout, ["Password:"]);
$exp->send("$password\n");
$exp->soft_close();
}

sub chmod_ssh_dir {
my $ssh_cmd  = "/usr/bin/ssh $username\@$host 'chmod 755 $ssh_dir'";

my $timeout  = '5';
my $exp      = Expect->spawn($ssh_cmd) or die "Cannot spawn ssh command \n";
$exp->expect($timeout, ["Password:"]);
$exp->send("$password\n");
$exp->soft_close();
}

sub push_ssh_key {
my $tmp_file  = "/tmp/authorized_keys.$$";
chomp $ssh_pub;

open  ( AUTHKEY, ">$tmp_file") || die ("Unable to create $tmp_file\n");
print AUTHKEY "$ssh_pub" . "\n";
close ( AUTHKEY );

my $scp_cmd  = "/usr/bin/scp $tmp_file $username\@$host:$ssh_dir/authorized_keys";

my $timeout = '5';
my $exp = Expect->spawn($scp_cmd) or die "Cannot spawn scp command \n";
$exp->expect($timeout, ["Password:"]);
$exp->send("$password\n");
$exp->soft_close();

unlink("$tmp_file");
}