fqdn_rotate: Don't use the value itself as part of the random seed

[elyscape]

Previously, the random number generator was seeded with the array or string to be rotated in addition to any values specifically provided for seeding. This behavior is potentially insecure in that it allows an attacker who can modify the source data to choose the post-shuffle order. While this is probably not a particularly big issue, it's still worth changing.

This also improves the documentation for fqdn_rotate.

[puppet-community-ci]

The result of the test was: PASS
Details at http://planck.nibalizer.com/buildlogs//puppetlabs+puppetlabs-stdlib+462+1432864204+PASS

I am a beta ci bot. I am probably lying to you.
You can contact nibalizer for more details

[DavidS]

Hi @elyscape , I think I like that change, but I'm having a hard time to put into words why this is needed. Would you mind enhancing the commit message to explain that?

[puppet-community-ci]

The result of the test was: PASS
Details at http://planck.nibalizer.com/buildlogs/puppetlabs+puppetlabs-stdlib+462+1432892309+PASS

I am a beta ci bot. I am probably lying to you.
You can contact nibalizer for more details.

[elyscape]

@DavidS: Sure. Will do.

[puppet-community-ci]

The result of the test was: PASS
Details at http://ci.puppet.community/buildlogs/puppetlabs+puppetlabs-stdlib+462+1433062069+PASS

I am a beta ci bot. I am probably lying to you.
You can contact nibalizer for more details.

[elyscape]

@DavidS: Done.

[elyscape]

Hold up, there's a bug in the spec tests.

[elyscape]

Or not. By chance, the rotation in this test is the same before and after the change.

That being said, question: why was this test added?

it {
  pending("Current implementation ignores parameters after the first.")
  is_expected.to run.with_params("one", "two").and_raise_error(Puppet::ParseError)
}

This has never been the case. It has always accepted a seed in the second parameter. In light of that, I have removed it.

[elyscape]

Ah, looks like there are no spec tests for the custom seed functionality. I'll add some real quick.

[puppet-community-ci]

The result of the test was: PASS
Details at http://ci.puppet.community/buildlogspuppetlabs+puppetlabs-stdlib+462+1433201432+PASS

I am a beta ci bot. I am probably lying to you.
You can contact nibalizer for more details.

[puppet-community-ci]

The result of the test was: PASS
Details at http://ci.puppet.community/buildlogspuppetlabs+puppetlabs-stdlib+462+1433202081+PASS

I am a beta ci bot. I am probably lying to you.
You can contact nibalizer for more details.

[elyscape]

Okay, improved spec tests are in. Improved acceptance tests will come in another PR that will also improve the acceptance tests for fqdn_rand_string().

[puppet-community-ci]

The result of the test was: PASS
Details at http://ci.puppet.community/buildlogspuppetlabs+puppetlabs-stdlib+462+1433202713+PASS

I am a beta ci bot. I am probably lying to you.
You can contact nibalizer for more details.

[puppet-community-ci]

The result of the test was: PASS
Details at http://ci.puppet.community/buildlogspuppetlabs+puppetlabs-stdlib+462+1433204642+PASS

I am a beta ci bot. I am probably lying to you.
You can contact nibalizer for more details.

[DavidS]

Thank you for this work!