Class: OsCtld::DistConfig::Distributions::Base

Inherits:
Object
  • Object
show all
Includes:
OsCtl::Lib::Utils::Log, OsCtl::Lib::Utils::System, Utils::SwitchUser
Defined in:
lib/osctld/dist_config/distributions/base.rb

Direct Known Subclasses

Arch, Debian, Gentoo, Guix, NixOS, OpenSuse, Other, RedHat, Slackware, Void

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Utils::SwitchUser

#ct_attach, #ct_syscmd

Constructor Details

#initialize(ctrc) ⇒ Base

Returns a new instance of Base.

Parameters:



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# File 'lib/osctld/dist_config/distributions/base.rb', line 21

def initialize(ctrc)
  @ctrc = ctrc
  @ct = ctrc.ct
  @distribution = ctrc.distribution
  @version = ctrc.version
end

Instance Attribute Details

#configurator ⇒ Object (readonly, protected)

Returns the value of attribute configurator.



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# File 'lib/osctld/dist_config/distributions/base.rb', line 243

def configurator
  @configurator
end

#ct ⇒ Object (readonly)

Returns the value of attribute ct.



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# File 'lib/osctld/dist_config/distributions/base.rb', line 18

def ct
  @ct
end

#ctrc ⇒ Object (readonly)

Returns the value of attribute ctrc.



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# File 'lib/osctld/dist_config/distributions/base.rb', line 18

def ctrc
  @ctrc
end

#distribution ⇒ Object (readonly)

Returns the value of attribute distribution.



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# File 'lib/osctld/dist_config/distributions/base.rb', line 18

def distribution
  @distribution
end

#version ⇒ Object (readonly)

Returns the value of attribute version.



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# File 'lib/osctld/dist_config/distributions/base.rb', line 18

def version
  @version
end

Class Method Details

.distribution(n = nil) ⇒ Object 



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# File 'lib/osctld/dist_config/distributions/base.rb', line 10

def self.distribution(n = nil)
  if n
    DistConfig.register(n, self)
  else
    n
  end
end

Instance Method Details

#add_netif(opts) ⇒ Object

Called when a new network interface is added to a container

Parameters:

  • opts (Hash)

Options Hash (opts):



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# File 'lib/osctld/dist_config/distributions/base.rb', line 183

def add_netif(opts)
  with_rootfs do
    configurator.add_netif(ct.netifs, opts[:netif])
  end
end

#apply_hostname ⇒ Object

Configure hostname in a running system



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# File 'lib/osctld/dist_config/distributions/base.rb', line 152

def apply_hostname
  log(:warn, ct, "Unable to apply hostname on #{distribution}: not implemented")
end

#bin_path(_opts) ⇒ String

Return path to ‘/bin` or an alternative, where a shell is looked up

Returns:

  • (String) 


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# File 'lib/osctld/dist_config/distributions/base.rb', line 233

def bin_path(_opts)
  '/bin'
end

#configurator_class ⇒ Object 



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# File 'lib/osctld/dist_config/distributions/base.rb', line 28

def configurator_class
  raise "define #{self.class}#configurator_class" unless self.class.const_defined?(:Configurator)

  cls = self.class::Configurator
  log(:debug, "Using #{cls} for #{ctrc.distribution}")
  cls
end

#dns_resolvers(_opts = {}) ⇒ Object 



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# File 'lib/osctld/dist_config/distributions/base.rb', line 208

def dns_resolvers(_opts = {})
  with_rootfs do
    configurator.dns_resolvers(ct.dns_resolvers)
  end
end

#log_type ⇒ Object 



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# File 'lib/osctld/dist_config/distributions/base.rb', line 237

def log_type
  ct.id
end

#network(_opts = {}) ⇒ Object 



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# File 'lib/osctld/dist_config/distributions/base.rb', line 174

def network(_opts = {})
  with_rootfs do
    configurator.network(ct.netifs)
  end
end

#passwd(opts) ⇒ Object

Parameters:

  • opts (Hash) —

    options

Options Hash (opts):

  • user (String)
  • password (String) 


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# File 'lib/osctld/dist_config/distributions/base.rb', line 217

def passwd(opts)
  ret = ct_syscmd(
    ct,
    %w[chpasswd],
    stdin: "#{opts[:user]}:#{opts[:password]}\n",
    run: true,
    valid_rcs: :all
  )

  return true if ret.success?

  log(:warn, ct, "Unable to set password: #{ret.output}")
end

#post_mount(opts) ⇒ Object

Run by LXC post-mount hook on container start

Parameters:

  • opts (Hash)

Options Hash (opts):

  • :ns_pid (Integer)
  • :rootfs_mount (String) 


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# File 'lib/osctld/dist_config/distributions/base.rb', line 80

def post_mount(opts)
  return unless volatile_is_systemd?

  ContainerControl::Commands::WithMountns.run!(
    ct,
    ns_pid: opts[:ns_pid],
    chroot: opts[:rootfs_mount],
    block: proc do
      # /run is mounted by {#pre_start}
      FileUtils.mkdir_p('/run/udev')

      # Create /run/udev/control if it isn't already there
      begin
        File.stat('/run/udev/control')
      rescue Errno::ENOENT
        File.new('/run/udev/control', 'w').close
      end

      true
    end
  )
end

#pre_start(_opts = {}) ⇒ Object

Called before container start, can be used to e.g. add temporary mounts



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# File 'lib/osctld/dist_config/distributions/base.rb', line 37

def pre_start(_opts = {})
  return unless volatile_is_systemd?
  # systemd by default does not monitor udev events in containers, which
  # means that there are no device units to depend on, e.g. for network
  # interfaces. systemd decides this by the  existence of socket
  # /run/udev/control and that /dev is devtmpfs. Our /dev cannot be
  # devtmpfs since that doesn't work in containers, and /run/udev/control
  # is created by a socket unit *after* systemd makes the decision to not
  # monitor udev events. After `systemctl daemon-reload`, it actually
  # starts to monitor udev events and the device units are created.
  #
  # See https://github.com/systemd/systemd/blob/729d2df8065ac90ac606e1fff91dc2d588b2795d/src/libsystemd/sd-device/device-monitor.c#L125
  #
  # We therefore mount /run as tmpfs before systemd is run and create
  # a stub for /run/udev/control, so that the check passes and udev events
  # are monitored from the start.
  #
  # /run has to be mounted by LXC from the container's user namespace, so
  # that it is owned by that user namespace. File /run/udev/control is
  # created later in {#post_mount}.

  # Check if /run isn't mounted already by user configuration
  return unless ct.mounts.detect { |mnt| %w[/run /run/].include?(mnt.mountpoint) }.nil?

  mem_limit = ct.find_memory_limit
  mnt_opts = %w[nosuid nodev mode=755 create=dir]
  mnt_opts << "size=#{mem_limit / 2}" if mem_limit

  ct.mounts.add(Mount::Entry.new(
                  'tmpfs',
                  '/run',
                  'tmpfs',
                  mnt_opts.join(','),
                  false,
                  temp: true,
                  in_config: true
                ))
end

#remove_netif(opts) ⇒ Object

Called when a network interface is removed from a container

Parameters:

  • opts (Hash)

Options Hash (opts):



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# File 'lib/osctld/dist_config/distributions/base.rb', line 192

def remove_netif(opts)
  with_rootfs do
    configurator.remove_netif(ct.netifs, opts[:netif])
  end
end

#rename_netif(opts) ⇒ Object

Called when an existing network interface is renamed

Parameters:

  • opts (Hash)

Options Hash (opts):



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# File 'lib/osctld/dist_config/distributions/base.rb', line 202

def rename_netif(opts)
  with_rootfs do
    configurator.rename_netif(ct.netifs, opts[:netif], opts[:original_name])
  end
end

#set_hostname(opts = {}) ⇒ Object

Set container hostname

Parameters:

  • opts (Hash) (defaults to: {}) —

    options

Options Hash (opts):

  • :original (OsCtl::Lib::Hostname) —

    previous hostname



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# File 'lib/osctld/dist_config/distributions/base.rb', line 142

def set_hostname(opts = {})
  with_rootfs do
    configurator.set_hostname(ct.hostname, old_hostname: opts[:original])
    configurator.update_etc_hosts(ct.hostname, old_hostname: opts[:original])
  end

  apply_hostname if ct.running?
end

#start(_opts = {}) ⇒ Object

Run just before the container is started



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# File 'lib/osctld/dist_config/distributions/base.rb', line 104

def start(_opts = {})
  return unless ct.hostname || ct.dns_resolvers || ctrc.dist_configure_network?

  net_configured = with_rootfs do
    ret = false

    set_hostname if ct.hostname
    dns_resolvers if ct.dns_resolvers

    if ctrc.dist_configure_network?
      network
      ret = true
    end

    ret
  end

  ctrc.dist_network_configured = true if net_configured
end

#stop(opts) ⇒ Object

Gracefully stop the container

Parameters:

  • opts (Hash)

Options Hash (opts):

  • :mode (:stop, :shutdown, :kill)
  • :message (String)
  • :timeout (Integer) 


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# File 'lib/osctld/dist_config/distributions/base.rb', line 129

def stop(opts)
  ContainerControl::Commands::Stop.run!(
    ct,
    opts[:mode],
    message: opts[:message],
    timeout: opts[:timeout]
  )
end

#unset_etc_hosts(_opts = {}) ⇒ Object

Remove the osctld-generated notice from /etc/hosts



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# File 'lib/osctld/dist_config/distributions/base.rb', line 168

def unset_etc_hosts(_opts = {})
  with_rootfs do
    configurator.unset_etc_hosts
  end
end

#update_etc_hosts(opts = {}) ⇒ Object

Update hostname in ‘/etc/hosts`, optionally removing configuration of old hostname.

Parameters:

  • opts (Hash) (defaults to: {}) —

    options

Options Hash (opts):

  • :old_hostname (OsCtl::Lib::Hostname, nil) 


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# File 'lib/osctld/dist_config/distributions/base.rb', line 161

def update_etc_hosts(opts = {})
  with_rootfs do
    configurator.update_etc_hosts(ct.hostname, old_hostname: opts[:old_hostname])
  end
end

#volatile_is_systemd? ⇒ Boolean (protected)

Check if the container is using systemd as init

This method accesses the container’s rootfs from the host, which is dangerous because of symlinks and we really shouldn’t be doing it… but in this case, we only do readlink(), so it shouldn’t do any harm.

Returns:

  • (Boolean) 


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# File 'lib/osctld/dist_config/distributions/base.rb', line 273

def volatile_is_systemd?
  return true if ctrc.distribution == 'nixos'

  begin
    File.readlink(File.join(ctrc.rootfs, 'sbin/init')).include?('systemd')
  rescue SystemCallError
    false
  end
end

#with_rootfs(&block) ⇒ Object (protected) 



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# File 'lib/osctld/dist_config/distributions/base.rb', line 245

def with_rootfs(&block)
  if @within_rootfs
    block.call
  else
    ContainerControl::Commands::WithRootfs.run!(
      ctrc.ct,
      ctrc:,
      block: proc do
        @configurator = configurator_class.new(
          ct.id,
          '/',
          ct.distribution,
          ct.version
        )
        @within_rootfs = true
        block.call
      end
    )
  end
end