test_snmp.rb

# $Id: testsnmp.rb 231 2006-12-21 15:09:29Z blackhedd $

require 'common'
require 'net/snmp'

class TestSnmp < Test::Unit::TestCase

  SnmpGetRequest = "0'\002\001\000\004\006public\240\032\002\002?*\002\001\000\002\001\0000\0160\f\006\b+\006\001\002\001\001\001\000\005\000"
  SnmpGetResponse = "0+\002\001\000\004\006public\242\036\002\002'\017\002\001\000\002\001\0000\0220\020\006\b+\006\001\002\001\001\001\000\004\004test"

  SnmpGetRequestXXX = "0'\002\001\000\004\006xxxxxx\240\032\002\002?*\002\001\000\002\001\0000\0160\f\006\b+\006\001\002\001\001\001\000\005\000"


  def setup
  end

  def teardown
  end

  def test_invalid_packet
      data = "xxxx"
      assert_raise( Net::BER::BerError ) {
	ary = data.read_ber(Net::SNMP::AsnSyntax)
      }

  end

  # The method String#read_ber! added by Net::BER consumes a well-formed BER object
  # from the head of a string. If it doesn't find a complete, well-formed BER object,
  # it returns nil and leaves the string unchanged. If it finds an object, it returns
  # the object and removes it from the head of the string. This is good for handling
  # partially-received data streams, such as from network connections.
  def test_consume_string
      data = "xxx"
      assert_equal( nil, data.read_ber! )
      assert_equal( "xxx", data )

      data = SnmpGetRequest + "!!!"
      ary = data.read_ber!( Net::SNMP::AsnSyntax )
      assert_equal( "!!!", data )
      assert ary.is_a?(Array)
      assert ary.is_a?(Net::BER::BerIdentifiedArray)
  end

  def test_weird_packet
      assert_raise( Net::SnmpPdu::Error ) {
	Net::SnmpPdu.parse("aaaaaaaaaaaaaa")
      }
  end

  def test_get_request
      data = SnmpGetRequest.dup
      pkt = data.read_ber(Net::SNMP::AsnSyntax)
      assert pkt.is_a?(Net::BER::BerIdentifiedArray)
      assert_equal( 48, pkt.ber_identifier) # Constructed [0], signifies GetRequest

      pdu = Net::SnmpPdu.parse(pkt)
      assert_equal(:get_request, pdu.pdu_type )
      assert_equal(16170, pdu.request_id ) # whatever was in the test data. 16170 is not magic.
      assert_equal( [[[1,3,6,1,2,1,1,1,0],nil]], pdu.variables )

      assert_equal( pdu.to_ber_string, SnmpGetRequest )
  end

  def test_empty_pdu
      pdu = Net::SnmpPdu.new
      assert_raise( Net::SnmpPdu::Error ) {
	pdu.to_ber_string
      }
  end

  def test_malformations
      pdu = Net::SnmpPdu.new
	pdu.version = 0
	pdu.version = 2
      assert_raise( Net::SnmpPdu::Error ) {
	pdu.version = 100
      }

      pdu.pdu_type = :get_request
      pdu.pdu_type = :get_next_request
      pdu.pdu_type = :get_response
      pdu.pdu_type = :set_request
      pdu.pdu_type = :trap
      assert_raise( Net::SnmpPdu::Error ) {
	pdu.pdu_type = :something_else
      }
  end

  def test_make_response
      pdu = Net::SnmpPdu.new
      pdu.version = 0
      pdu.community = "public"
      pdu.pdu_type = :get_response
      pdu.request_id = 9999
      pdu.error_status = 0
      pdu.error_index = 0
      pdu.add_variable_binding [1,3,6,1,2,1,1,1,0], "test"

      assert_equal( SnmpGetResponse,  pdu.to_ber_string )
  end

  def test_make_bad_response
      pdu = Net::SnmpPdu.new
      assert_raise(Net::SnmpPdu::Error) {pdu.to_ber_string}
      pdu.pdu_type = :get_response
      pdu.request_id = 999
      pdu.to_ber_string
      # Not specifying variables doesn't create an error. (Maybe it should?)
  end

  def test_snmp_integers
      c32 = Net::SNMP::Counter32.new(100)
      assert_equal( "A\001d", c32.to_ber )
      g32 = Net::SNMP::Gauge32.new(100)
      assert_equal( "B\001d", g32.to_ber )
      t32 = Net::SNMP::TimeTicks32.new(100)
      assert_equal( "C\001d", t32.to_ber )
  end

  def test_community
      data = SnmpGetRequestXXX.dup
      ary = data.read_ber(Net::SNMP::AsnSyntax)
      pdu = Net::SnmpPdu.parse( ary )
      assert_equal( "xxxxxx", pdu.community )
  end

end