Merge pull request #39 from fgrehm/port-forwarding

Port forwarding support using redir

README.md

@@ -5,12 +5,12 @@ Highly experimental Linux Containers support for Vagrant 1.1.
 
 ## Dependencies
 
-Vagrant >= 1.1.0, the `lxc` package and a Kernel [higher than 3.5.0-17.28](#help-im-unable-to-restart-containers),
+Vagrant >= 1.1.0, `lxc` and `redir` packages and a Kernel [higher than 3.5.0-17.28](#help-im-unable-to-restart-containers),
 which on Ubuntu 12.10 means something like:
 
 ```
 sudo apt-get update && sudo apt-get dist-upgrade
-sudo apt-get install lxc
+sudo apt-get install lxc redir
 wget "http://files.vagrantup.com/packages/67bd4d30f7dbefa7c0abc643599f0244986c38c8/vagrant_`uname -m`.deb" -O /tmp/vagrant.deb
 sudo dpkg -i /tmp/vagrant.deb
 ```
@@ -22,6 +22,7 @@ sudo dpkg -i /tmp/vagrant.deb
 * Shared folders
 * Provisioning
 * Setting container's host name
+* Port forwarding
 
 *Please refer to the [closed issues](https://github.com/fgrehm/vagrant-lxc/issues?labels=&milestone=&page=1&state=closed)
 for the most up to date list.*
@@ -29,7 +30,7 @@ for the most up to date list.*
 
 ## Current limitations
 
-* Port forwarding does not work [yet](https://github.com/fgrehm/vagrant-lxc/issues/6)
+* Port forwarding collision detection
 * A hell lot of `sudo`s
 * Only a [single ubuntu box supported](boxes), I'm still [figuring out what should go
   on the .box file](https://github.com/fgrehm/vagrant-lxc/issues/4)

development/site.pp

@@ -20,7 +20,8 @@ exec {
 
 # Install dependencies
 package {
-  [ 'libffi-dev', 'bsdtar', 'exuberant-ctags', 'ruby1.9.1-dev', 'htop', 'git', 'build-essential' ]:
+  [ 'libffi-dev', 'bsdtar', 'exuberant-ctags', 'ruby1.9.1-dev', 'htop', 'git',
+    'build-essential', 'redir' ]:
     ensure   => 'installed'
   ;
 

lib/vagrant-lxc/action.rb

@@ -5,11 +5,13 @@ require 'vagrant-lxc/action/base_action'
 require 'vagrant-lxc/action/boot'
 require 'vagrant-lxc/action/check_created'
 require 'vagrant-lxc/action/check_running'
+require 'vagrant-lxc/action/clear_forwarded_ports'
 require 'vagrant-lxc/action/create'
 require 'vagrant-lxc/action/created'
 require 'vagrant-lxc/action/destroy'
 require 'vagrant-lxc/action/disconnect'
 require 'vagrant-lxc/action/forced_halt'
+require 'vagrant-lxc/action/forward_ports'
 require 'vagrant-lxc/action/handle_box_metadata'
 require 'vagrant-lxc/action/is_running'
 require 'vagrant-lxc/action/network'
@@ -55,10 +57,10 @@ module Vagrant
           # b.use ClearSharedFolders
           b.use ShareFolders
           b.use Network
-          # b.use ForwardPorts
           b.use Vagrant::Action::Builtin::SetHostname
           # b.use SaneDefaults
           # b.use Customize
+          b.use ForwardPorts
           b.use Boot
         end
       end
@@ -131,6 +133,7 @@ module Vagrant
             if env[:result]
               # TODO: If vagrant >=...
               b2.use Disconnect
+              b2.use ClearForwardedPorts
               b2.use Vagrant::Action::Builtin::Call, Vagrant::Action::Builtin::GracefulHalt, :stopped, :running do |env2, b3|
                 if !env2[:result] && env2[:machine].provider.state.running?
                   b3.use ForcedHalt

lib/vagrant-lxc/action/clear_forwarded_ports.rb

@@ -0,0 +1,47 @@
+module Vagrant
+  module LXC
+    module Action
+      class ClearForwardedPorts
+        def initialize(app, env)
+          @app = app
+          @logger = Log4r::Logger.new("vagrant::lxc::action::clear_forwarded_ports")
+        end
+
+        def call(env)
+          @env = env
+
+          if redir_pids.any?
+            env[:ui].info I18n.t("vagrant.actions.vm.clear_forward_ports.deleting")
+            redir_pids.each do |pid|
+              next unless is_redir_pid?(pid)
+              @logger.debug "Killing pid #{pid}"
+              system "sudo pkill -9 -P #{pid}"
+            end
+
+            remove_redir_pids
+          end
+
+          @app.call env
+        end
+
+        protected
+
+        def redir_pids
+          @redir_pids = Dir[@env[:machine].data_dir.join('pids').to_s + "/redir_*.pid"].map do |file|
+            File.read(file).strip.chomp
+          end
+        end
+
+        def is_redir_pid?(pid)
+          `ps -o cmd= #{pid}`.strip.chomp =~ /redir/
+        end
+
+        def remove_redir_pids
+          Dir[@env[:machine].data_dir.join('pids').to_s + "/redir_*.pid"].each do |file|
+            File.delete file
+          end
+        end
+      end
+    end
+  end
+end

lib/vagrant-lxc/action/forward_ports.rb

@@ -0,0 +1,83 @@
+module Vagrant
+  module LXC
+    module Action
+      class ForwardPorts
+        def initialize(app, env)
+          @app    = app
+          @logger = Log4r::Logger.new("vagrant::lxc::action::forward_ports")
+        end
+
+        def call(env)
+          @env = env
+
+          # Continue, we need the VM to be booted in order to grab its IP
+          @app.call env
+
+          # Get the ports we're forwarding
+          env[:forwarded_ports] = compile_forwarded_ports(env[:machine].config)
+
+          # Warn if we're port forwarding to any privileged ports
+          env[:forwarded_ports].each do |fp|
+            if fp[:host] <= 1024
+              env[:ui].warn I18n.t("vagrant.actions.vm.forward_ports.privileged_ports")
+              break
+            end
+          end
+
+          env[:ui].info I18n.t("vagrant.actions.vm.forward_ports.forwarding")
+          forward_ports
+        end
+
+        def forward_ports
+          @container_ip = @env[:machine].provider.container.assigned_ip
+
+          @env[:forwarded_ports].each do |fp|
+            message_attributes = {
+              # TODO: Add support for multiple adapters
+              :adapter    => 'eth0',
+              :guest_port => fp[:guest],
+              :host_port  => fp[:host]
+            }
+
+            # TODO: Remove adapter from logging
+            @env[:ui].info(I18n.t("vagrant.actions.vm.forward_ports.forwarding_entry",
+                                  message_attributes))
+
+            redir_pid = redirect_port(fp[:host], fp[:guest])
+            store_redir_pid(fp[:host], redir_pid)
+          end
+        end
+
+        private
+
+        def compile_forwarded_ports(config)
+          mappings = {}
+
+          config.vm.networks.each do |type, options|
+            if type == :forwarded_port
+              mappings[options[:host]] = options
+            end
+          end
+
+          mappings.values
+        end
+
+        def redirect_port(host, guest)
+          redir_cmd = "sudo redir --laddr=127.0.0.1 --lport=#{host} --cport=#{guest} --caddr=#{@container_ip}"
+
+          @logger.debug "Forwarding port with `#{redir_cmd}`"
+          fork { exec redir_cmd }
+        end
+
+        def store_redir_pid(host_port, redir_pid)
+          data_dir = @env[:machine].data_dir.join('pids')
+          data_dir.mkdir unless data_dir.directory?
+
+          data_dir.join("redir_#{host_port}.pid").open('w') do |pid_file|
+            pid_file.write(redir_pid)
+          end
+        end
+      end
+    end
+  end
+end

spec/spec_helper.rb

@@ -7,6 +7,8 @@ end
 
 require 'bundler/setup'
 
+require 'i18n'
+
 require 'rspec-spies'
 
 Dir[File.dirname(__FILE__) + "/support/**/*.rb"].each { |f| require f }

spec/unit/action/clear_forwarded_ports_spec.rb

@@ -0,0 +1,42 @@
+require 'unit_helper'
+
+require 'vagrant-lxc/action/clear_forwarded_ports'
+
+describe Vagrant::LXC::Action::ClearForwardedPorts do
+  let(:app)       { mock(:app, call: true) }
+  let(:env)       { {machine: machine, ui: stub(info: true)} }
+  let(:machine)   { mock(:machine, data_dir: data_dir) }
+  let!(:data_dir) { Pathname.new(Dir.mktmpdir) }
+  let(:pids_dir)  { data_dir.join('pids') }
+  let(:pid)       { 'a-pid' }
+  let(:pid_cmd)   { 'redir' }
+
+  subject { described_class.new(app, env) }
+
+  before do
+    pids_dir.mkdir
+    pids_dir.join('redir_1234.pid').open('w') { |f| f.write(pid) }
+    subject.stub(system: true, :` => pid_cmd)
+    subject.call(env)
+  end
+
+  after { FileUtils.rm_rf data_dir.to_s }
+
+  it 'removes all files under pid directory' do
+    Dir[pids_dir.to_s + "/redir_*.pid"].should be_empty
+  end
+
+  context 'with a valid redir pid' do
+    it 'kills known processes' do
+      subject.should have_received(:system).with("sudo pkill -9 -P #{pid}")
+    end
+  end
+
+  context 'with an invalid pid' do
+    let(:pid_cmd)   { 'sudo ls' }
+
+    it 'does not kill the process' do
+      subject.should_not have_received(:system).with("sudo pkill -9 -P #{pid}")
+    end
+  end
+end

spec/unit/action/forward_ports_spec.rb

@@ -0,0 +1,41 @@
+require 'unit_helper'
+
+require 'vagrant-lxc/action/forward_ports'
+
+describe Vagrant::LXC::Action::ForwardPorts do
+  let(:app)          { mock(:app, call: true) }
+  let(:env)          { {machine: machine, ui: stub(info: true)} }
+  let(:machine)      { mock(:machine) }
+  let!(:data_dir)    { Pathname.new(Dir.mktmpdir) }
+  let(:networks)     { [[:other_config, {}], [:forwarded_port, {guest: guest_port, host: host_port}]] }
+  let(:host_port)    { 8080 }
+  let(:guest_port)   { 80 }
+  let(:provider)     { fire_double('Vagrant::LXC::Provider', container: container) }
+  let(:container)    { fire_double('Vagrant::LXC::Container', assigned_ip: container_ip) }
+  let(:container_ip) { '10.0.1.234' }
+  let(:pid)          { 'a-pid' }
+
+  subject { described_class.new(app, env) }
+
+  before do
+    machine.stub_chain(:config, :vm, :networks).and_return(networks)
+    machine.stub(provider: provider, data_dir: data_dir)
+
+    subject.stub(exec: true)
+    subject.stub(:fork) { |&block| block.call; pid }
+    subject.call(env)
+  end
+
+  after { FileUtils.rm_rf data_dir.to_s }
+
+  it 'forwards ports using redir' do
+    subject.should have_received(:exec).with(
+      "sudo redir --laddr=127.0.0.1 --lport=#{host_port} --cport=#{guest_port} --caddr=#{container_ip}"
+    )
+  end
+
+  it "stores redir pids on machine's data dir" do
+    pid_file = data_dir.join('pids', "redir_#{host_port}.pid").read
+    pid_file.should == pid
+  end
+end