Module: User

Extended by:
User
Included in:
User
Defined in:
lib/nub/user.rb

Overview

Some user related helper methods

Instance Method Summary collapse

Instance Method Details

#drop_privileges ⇒ Object

Drop root privileges to original user

Parameters:

  • optional (Proc) —

    block to execut in context of user



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# File 'lib/nub/user.rb', line 53

def drop_privileges
  result = nil
  uid = gid = nil

  # Drop privileges
  if Process.uid.zero?
    uid, gid = Process.uid, Process.gid
    user_uid = ENV['SUDO_UID'].to_i
    user_gid = ENV['SUDO_GID'].to_i
    Process::GID.grant_privilege(user_gid)
    Process::UID.grant_privilege(user_uid)
  end

  # Execute block if given
  begin
    result = Proc.new.call
    self.raise_privileges(uid, gid)
  rescue ArgumentError
    # No block given just return ids
    result = [uid, gid]
  rescue
    self.raise_privileges(uid, gid)
  end

  return result
end

#drop_privileges! ⇒ Object

Correctly and permanently drops privileges timetobleed.com/5-things-you-dont-know-about-user-ids-that-will-destroy-you/ requires you drop the group before the user and use a safe solution



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# File 'lib/nub/user.rb', line 42

def drop_privileges!
  if Process.uid.zero?
    nobody = Etc.getpwnam('nobody')
    Process::Sys.setresgid(nobody.gid, nobody.gid, nobody.gid)
    Process::Sys.setresuid(nobody.uid, nobody.uid, nobody.uid)
  end
end

#name ⇒ Object

Get the real user taking into account sudo priviledges



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# File 'lib/nub/user.rb', line 35

def name
  return Process.uid.zero? ? Etc.getpwuid(ENV['SUDO_UID'].to_i).name : ENV['USER']
end

#raise_privileges(uid, gid) ⇒ Object

Raise privileges if dropped earlier

Parameters:

  • uid (String) —

    uid of user to assume

  • gid (String) —

    gid of user to assume



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# File 'lib/nub/user.rb', line 83

def raise_privileges(uid, gid)
  if uid and gid
    Process::UID.grant_privilege(uid)
    Process::GID.grant_privilege(gid)
  end
end

#root? ⇒ Boolean

Check if the current user has root privileges

Returns:

  • (Boolean) 


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# File 'lib/nub/user.rb', line 30

def root?
  return Process.uid.zero?
end