mysqlchecker.py

监控大型网络的软件。能够自动发现拓扑结构

# -*- coding: UTF-8 -*-
#
# Copyright 2007 University of Troms酶
#
# This file is part of Network Administration Visualized (NAV)
#
# NAV is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# NAV is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with NAV; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
#
# $Id: MysqlChecker.py 3966 2007-04-12 12:00:06Z mortenv $
# Author: Ole Martin Bj酶rndalen <[e-mail]>
#

import socket
from nav.statemon.abstractChecker import AbstractChecker
from nav.statemon.event import Event

class MysqlError(Exception):
	pass

class MysqlConnection:
	"""
	Very minimal implementation of MySQL protocol.
	(Packet layer only.)
	Error messages from the server raise MysqlError exceptions.
	"""
	
	def __init__(self, addr, timeout=None):
		sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
		if timeout != None:
			sock.settimeout(timeout)
		sock.connect(addr)
		self.file = sock.makefile('r+')

		self.seqno = 0

	def read_packet(self):
		header = self.file.read(4)

		ll = ord(header[0])
		mm = ord(header[1])
		hh = ord(header[2])
		size = hh << 16 | mm << 8 | ll
		seqno = ord(header[3])

		self.seqno = seqno

		data = self.file.read(size)

		if data.startswith('\xff'):
			raise MysqlError(data[3:])
		
		return data

	def write_packet(self, data):
		size = len(data)
		ll = size >> 16
		mm = (size >> 8) & 0xff 
		hh = size & 0xff 
		seqno = self.seqno = (self.seqno + 1) % 256

		header = '%c%c%c%c' % (hh, mm, ll, seqno)

		self.file.write(header + data)
		self.file.flush()

	def write_auth_packet(self, username):
		data = '\x85\xa4\x00\x00\x00%s\x00\x00' % username
		self.write_packet(data)

	def close(self):
		self.write_packet(chr(1))  # Send COM_QUIT
		self.file.close()
			
class MysqlChecker(AbstractChecker):
	def __init__(self,service, **kwargs):
		AbstractChecker.__init__(self, "mysql", service, port=3306, **kwargs)

	def execute(self):

		try:
			#
			# Connect and read handshake packet.
			#
			conn = MysqlConnection(self.getAddress(), self.getTimeout())
			data = conn.read_packet()

			#
			# Get server version from handshake
			#
			version = data[1:].split('\0')[0]  # Null terminated string
			self.setVersion(version)

			#
			# Send authentication packet to make server happy.
			# (If we don't do this, the server will be angry at
			# us for a while.)
			#
			conn.write_auth_packet('navmon')
			try:
				conn.read_packet()
			except MysqlError, err:
				pass  # Ignore login error

			conn.close()

			return Event.UP, 'OK'
		
		except MysqlError, err:
			return Event.DOWN, str(err)
			
	
def getRequiredArgs():
	"""
	Returns a list of required arguments
	"""
	requiredArgs = []
	return requiredArgs