onlyif return code

[Björn]

Hello,

I try to ensure our password policies using /etc/login.defs and PAM cracklib.

class pci_policy::password(
    $cracklib = $pci_policy::params::cracklib,
    $pam_password = $pci_policy::params::pam_password,
) inherits pci_policy::params {

  package{$cracklib:
    ensure => installed,
  }

  file{'/etc/login.defs':
    ensure  => present,
    owner   => root,
    group   => root,
    mode    => 0644,
    source  => "puppet:///modules/pci_policy/login.defs.$::operatingsystem",
    require => Package[$cracklib],
  }

  exec{'ensure password policy for pci':
    cwd     => '/bin/',
    command => "/bin/sed -i 's/^password.*cracklib.so.*/password        requisite                       pam_cracklib.so retry=3 minlen=8 difok=5 dcredit=-1 lcredit=-1 ucredit=-1 ocredit=-1/g' $pam_password",
    path    => "/usr/bin:/usr/sbin:/bin",
    onlyif  => "grep '^password.*cracklib.so.*' $pam_password",
    require => Package[$cracklib],
  }

  exec{'ensure password policy for pci when nothing is present':
    cwd     => '/bin/',
    command => "echo 'password        requisite                       pam_cracklib.so retry=3 minlen=8 difok=5 dcredit=-1 lcredit=-1 ucredit=-1 ocredit=-1' >> $pam_password",
    path    => "/usr/bin:/usr/sbin:/bin",
    onlyif  => "grep -vq '^password.*cracklib.so.*' $pam_password",
    require => Package[$cracklib],
  }
}

My problem are the exec commands.

With the first exec I try to change an existing line with sed.

With the second exec I try to add the rule if no line with "password.*cracklib" is existing.
Unfortunately, this exec run when the return code of onlyif is 0. I don't know a command which return 0 when the line isn't available and return 1 when the line is available.

May be I'm thinking to complicated? Do you have another solution?

Thanks a lot!

Björn

[Mike Delaney]

On Wed, Oct 2, 2013 at 4:15 AM, Björn <bbecke...@googlemail.com> wrote:

  exec{'ensure password policy for pci':
    cwd     => '/bin/',
    command => "/bin/sed -i 's/^password.*cracklib.so.*/password        requisite                       pam_cracklib.so retry=3 minlen=8 difok=5 dcredit=-1 lcredit=-1 ucredit=-1 ocredit=-1/g' $pam_password",
    path    => "/usr/bin:/usr/sbin:/bin",
    onlyif  => "grep '^password.*cracklib.so.*' $pam_password",
    require => Package[$cracklib],
  }

  exec{'ensure password policy for pci when nothing is present':
    cwd     => '/bin/',
    command => "echo 'password        requisite                       pam_cracklib.so retry=3 minlen=8 difok=5 dcredit=-1 lcredit=-1 ucredit=-1 ocredit=-1' >> $pam_password",
    path    => "/usr/bin:/usr/sbin:/bin",
    onlyif  => "grep -vq '^password.*cracklib.so.*' $pam_password",
    require => Package[$cracklib],
  }
}

My problem are the exec commands.

With the first exec I try to change an existing line with sed.

With the second exec I try to add the rule if no line with "password.*cracklib" is existing.
Unfortunately, this exec run when the return code of onlyif is 0. I don't know a command which return 0 when the line isn't available and return 1 when the line is available.

May be I'm thinking to complicated? Do you have another solution?

Off the top of my head, I can't think of a way to invert grep's exit status like you want (at least not a way
that will work in an onlyif), however the use of two execs to modify a file is probably not the ideal solution.
Indeed, once the cracklib entry is present in the file, that first exec will fire every time puppet runs, which
is probably not what you want either.

If you don't want to manage the entire file, you could use either the native augeas type or the file_line
type from the stdlib module to accomplish what you want (file_line is probably easier):

  file_line { 'ensure password policy for pci':

    path    => $pam_password,

    match => '^password.*cracklib\.so',

    line     => 'password        requisite                     

  pam_cracklib.so retry=3 minlen=8 difok=5 dcredit=-1 lcredit=-1 ucredit=-1 ocredit=-1'

}

-Mike

[james.e...@fasthosts.com]

 The exec resource has an unless parameter too which I think is what you need.

From: http://docs.puppetlabs.com/references/latest/type.html#exec

onlyif

If this parameter is set, then this exec will only run if the command returns 0

unless

If this parameter is set, then this exec will run unless the command returns 0

[Björn]

Hello Mike,

thanks a lot, file_line works great! I not remember why I don't use file_line for such things.

Björn

[Björn]

Unless was also a good hint! But my sed solution was running every time puppet agent run. So I use file_line now.

Thanks!