Add recipe lyraphase_workstation::loopback_alias_ip for re-creating I…

…P alias on lo0 every reboot (For use with Docker for Mac)

Use case: Docker container == socks5h:// ==> Alias IP of macOS Host running SSH Tunnel => Bastion Host

See diagram: https://gist.github.com/trinitronx/6427d6454fb3b121fc2ab5ca7ac766bc

References:

 - [user-defined networks](https://docs.docker.com/network/bridge/##differences-between-user-defined-bridges-and-the-default-bridge)

 - [Docker forum thread: Connecting docker container to macOS Host](https://forums.docker.com/t/accessing-host-machine-from-within-docker-container/14248/13)

 - [Terraform enhancement request for SOCKS5h support and Explanation of Use Case](hashicorp/terraform#17754 (comment))

attributes/loopback_alias_ip.rb

@@ -0,0 +1,2 @@
+default['lyraphase_workstation']['loopback_alias_ip'] = {}
+default['lyraphase_workstation']['loopback_alias_ip']['alias_ip'] = '172.16.222.111'

recipes/loopback_alias_ip.rb

@@ -0,0 +1,37 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2018 James Cuzella
+# 
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+loopback_alias_ip = nil
+if ! node['lyraphase_workstation']['loopback_alias_ip'].nil? && ! node['lyraphase_workstation']['loopback_alias_ip']['alias_ip'].nil?
+  loopback_alias_ip = node['lyraphase_workstation']['loopback_alias_ip']['alias_ip']
+end
+
+template "/Library/LaunchDaemons/com.runlevel1.lo0.alias.plist" do
+  source "com.runlevel1.lo0.alias.plist.erb"
+  user "root"
+  group "wheel"
+  mode "0644"
+  variables({ loopback_alias_ip: loopback_alias_ip })
+  notifies :run, 'execute[load the com.runlevel1.lo0.alias plist into launchd]'
+end
+
+execute "load the com.runlevel1.lo0.alias plist into launchd" do
+  command "launchctl load -w /Library/LaunchDaemons/com.runlevel1.lo0.alias.plist"
+  user node['lyraphase_workstation']['user']
+  not_if 'launchctl list com.runlevel1.lo0.alias'
+end

spec/unit/recipes/loopback_alias_ip_spec.rb

@@ -0,0 +1,61 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2018 James Cuzella
+# 
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+require 'spec_helper'
+
+describe 'lyraphase_workstation::loopback_alias_ip' do
+
+  let(:launchd_plist) { "/Library/LaunchDaemons/com.runlevel1.lo0.alias.plist" }
+  let(:loopback_alias_ip) { '172.16.222.111' }
+
+  let(:chef_run) {
+    klass = ChefSpec.constants.include?(:SoloRunner) ? ChefSpec::SoloRunner : ChefSpec::Runner
+    klass.new(platform: 'mac_os_x', version: '10.11.1') do |node|
+      create_singleton_struct "EtcPasswd", [ :name, :passwd, :uid, :gid, :gecos, :dir, :shell, :change, :uclass, :expire ]
+      node.normal['etc']['passwd']['brubble'] = Struct::EtcPasswd.new('brubble', '********', 501, 20, 'Barney Rubble', '/Users/brubble', '/bin/bash', 0, '', 0)
+      node.normal['lyraphase_workstation']['user'] = 'brubble'
+      node.normal['lyraphase_workstation']['home'] = '/Users/brubble'
+
+      stub_command("which git").and_return('/usr/local/bin/git')
+
+      stub_command('launchctl list com.runlevel1.lo0.alias').and_return(true)
+    end.converge(described_recipe)
+  }
+
+  it 'installs launchd plist for adding IP alias to loopback network interface lo0' do
+    expect(chef_run).to create_template(launchd_plist).with(
+      user:   'root',
+      group:  'wheel',
+      mode:   '0644'
+    )
+    expect(chef_run).to render_file(launchd_plist).with_content(Regexp.new("^\\s+<string>/sbin/ifconfig</string>$"))
+    expect(chef_run).to render_file(launchd_plist).with_content(Regexp.new("^\\s+<string>#{loopback_alias_ip}</string>$"))
+
+    expect(chef_run.template(launchd_plist)).to notify('execute[load the com.runlevel1.lo0.alias plist into launchd]').to(:run)
+  end
+
+  context "when launchd plist is already loaded" do
+    before(:all) do
+      stub_command('launchctl list com.runlevel1.lo0.alias').and_return(true)
+    end
+
+    it "skips loading com.runlevel1.lo0.alias launchd plist file" do
+      expect(chef_run.execute('load the com.runlevel1.lo0.alias plist into launchd')).to do_nothing
+    end
+  end
+end
+

templates/default/com.runlevel1.lo0.alias.plist.erb

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+  <dict>
+      <key>Label</key>
+      <string>com.runlevel1.lo0.alias</string>
+      <key>RunAtLoad</key>
+      <true/>
+      <key>ProgramArguments</key>
+      <array>
+          <string>/sbin/ifconfig</string>
+          <string>lo0</string>
+          <string>alias</string>
+          <string><%= @loopback_alias_ip %></string>
+          <string>up</string>
+      </array>
+      <key>StandardErrorPath</key>
+      <string>/var/log/loopback-alias.log</string>
+      <key>StandardOutPath</key>
+      <string>/var/log/loopback-alias.log</string>
+      <key>UserName</key>
+      <string>root</string>
+  </dict>
+</plist>