Module: Puppet::Util::SUIDManager

Extended by:
Forwardable
Includes:
Warnings
Defined in:
lib/puppet/util/suidmanager.rb

Class Method Summary collapse

Methods included from Warnings

clear_warnings, debug_once, maybe_log, notice_once, warnonce

Class Method Details

.asuser(new_uid = nil, new_gid = nil) ⇒ Object

Runs block setting euid and egid if provided then restoring original ids. If running on Windows or without root, the block will be run with the current euid/egid.



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# File 'lib/puppet/util/suidmanager.rb', line 63

def asuser(new_uid = nil, new_gid = nil)
  return yield if Puppet::Util::Platform.windows?
  return yield unless root?
  return yield unless new_uid or new_gid

  old_euid = euid
  old_egid = egid
  begin
    change_privileges(new_uid, new_gid, false)

    yield
  ensure
    change_privileges(new_uid ? old_euid : nil, old_egid, false)
  end
end

.change_group(group, permanently = false) ⇒ Object

Changes the egid of the process if ‘permanently` is not set, otherwise changes gid. This method will fail if used on Windows, or attempting to change to a different gid without root.

Raises:



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# File 'lib/puppet/util/suidmanager.rb', line 101

def change_group(group, permanently = false)
  gid = convert_xid(:gid, group)
  raise Puppet::Error, _("No such group %{group}") % { group: group } unless gid

  return if Process.egid == gid

  if permanently
    Process::GID.change_privilege(gid)
  else
    Process.egid = gid
  end
end

.change_privileges(uid = nil, gid = nil, permanently = false) ⇒ Object

If ‘permanently` is set, will permanently change the uid/gid of the process. If not, it will only set the euid/egid. If only uid is supplied, the primary group of the supplied gid will be used. If only gid is supplied, only gid will be changed. This method will fail if used on Windows.



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# File 'lib/puppet/util/suidmanager.rb', line 85

def change_privileges(uid = nil, gid = nil, permanently = false)
  return unless uid or gid

  unless gid
    uid = convert_xid(:uid, uid)
    gid = Etc.getpwuid(uid).gid
  end

  change_group(gid, permanently)
  change_user(uid, permanently) if uid
end

.change_user(user, permanently = false) ⇒ Object

As change_group, but operates on uids. If changing user permanently, supplementary groups will be set the to default groups for the new uid.

Raises:



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# File 'lib/puppet/util/suidmanager.rb', line 117

def change_user(user, permanently = false)
  uid = convert_xid(:uid, user)
  raise Puppet::Error, _("No such user %{user}") % { user: user } unless uid

  return if Process.euid == uid

  if permanently
    # If changing uid, we must be root. So initgroups first here.
    initgroups(uid)

    Process::UID.change_privilege(uid)
  elsif Process.euid == 0
    # We must be root to initgroups, so initgroups before dropping euid if
    # we're root, otherwise elevate euid before initgroups.
    # change euid (to root) first.
    initgroups(uid)
    Process.euid = uid
  else
    Process.euid = uid
    initgroups(uid)
  end
end

.convert_xid(type, id) ⇒ Object

Make sure the passed argument is a number.

Raises:

  • (ArgumentError) 


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# File 'lib/puppet/util/suidmanager.rb', line 142

def convert_xid(type, id)
  return id if id.is_a? Integer

  map = { :gid => :group, :uid => :user }
  raise ArgumentError, _("Invalid id type %{type}") % { type: type } unless map.include?(type)

  ret = Puppet::Util.send(type, id)
  if ret.nil?
    raise Puppet::Error, _("Invalid %{klass}: %{id}") % { klass: map[type], id: id }
  end

  ret
end

.groups=(grouplist) ⇒ Object 



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# File 'lib/puppet/util/suidmanager.rb', line 27

def groups=(grouplist)
  Process.groups = grouplist
rescue Errno::EINVAL => e
  # We catch Errno::EINVAL as some operating systems (OS X in particular) can
  # cause troubles when using Process#groups= to change *this* user / process
  # list of supplementary groups membership.  This is done via Ruby's function
  # "static VALUE proc_setgroups(VALUE obj, VALUE ary)" which is effectively
  # a wrapper for "int setgroups(size_t size, const gid_t *list)" (part of SVr4
  # and 4.3BSD but not in POSIX.1-2001) that fails and sets errno to EINVAL.
  #
  # This does not appear to be a problem with Ruby but rather an issue on the
  # operating system side.  Therefore we catch the exception and look whether
  # we run under OS X or not -- if so, then we acknowledge the problem and
  # re-throw the exception otherwise.
  if !osx_maj_ver || osx_maj_ver.empty?
    raise e
  end
end

.initgroups(uid) ⇒ Object

Initialize primary and supplemental groups to those of the target user. We take the UID and manually look up their details in the system database, including username and primary group. This method will fail on Windows, or if used without root to initgroups of another user.



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# File 'lib/puppet/util/suidmanager.rb', line 161

def initgroups(uid)
  pwent = Etc.getpwuid(uid)
  Process.initgroups(pwent.name, pwent.gid)
end

.osx_maj_ver ⇒ Object 



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# File 'lib/puppet/util/suidmanager.rb', line 20

def osx_maj_ver
  return @osx_maj_ver unless @osx_maj_ver.nil?

  @osx_maj_ver = Puppet.runtime[:facter].value('os.macosx.version.major') || false
end

.root? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/puppet/util/suidmanager.rb', line 47

def self.root?
  if Puppet::Util::Platform.windows?
    require_relative '../../puppet/util/windows/user'
    Puppet::Util::Windows::User.admin?
  else
    Process.uid == 0
  end
end