FileSystem Level IDS in python

ids.py

#!/usr/bin/python3

import hashlib
import os
import argparse
import pickle
import sys
import time


CHUNK_SIZE = 10240
#SCAN

hashDict ={ 'metadata':{} , 'header':{}}
#hashDict ={  'header':{}}
hashListRescan = []

parser = argparse.ArgumentParser(description="")
parser.add_argument('-i',  help='Initalize the database.' ,dest='dbInitialize', action='store_true', default=False)
parser.add_argument('-f',  help='File to store the Meta-data.' , dest='dbName',metavar='')
parser.add_argument('-d',  help='Directory Name To Scan' , dest='dirName',metavar='',nargs='+')
parser.add_argument('-r',  help='Re-Scan the MetaData.', dest='dbReScan',action='store_true', default=False)
args = parser.parse_args()

DB_initailize = args.dbInitialize
DB_name= args.dbName
DB_rescan = args.dbReScan
DIR_names = args.dirName

def printHelp():
  print('')
  print(' INTIALIZE : ids.py  -i  -d dir1 dir2 ..  -f somefile.db')
  print(' RE-SCAN : ids.py  -r  -f somefile.db')
  print('')
  
# This funtion will return the hash value of a resource.
# resource can be a file(rtype=f) or string(rtype=s)
def getHash(resource,rtype='f'):
    if rtype == 'f': 
      fh = open(resource,'rb')
      md5sum = hashlib.new('md5')
      while True:
        chunk = fh.read(CHUNK_SIZE)
        if not chunk:
          break
        md5sum.update(chunk)
      return md5sum.hexdigest()
    if rtype == 's':
      md5sum = hashlib.new('md5')
      md5sum.update(resource.encode('utf-8'))
      return md5sum.hexdigest()

def creatingHeader():
  headerDict = {}
  headerDict['date'] = time.strftime("%d-%b-%Y-%H-%M-%S")
  headerDict['directory'] = DIR_names
  hashDict['header'].update(headerDict)
  return None

# dictName can be hashDict 0r hashDictRescan
def metaDictToHashDict(fileName): 
  statInfo = os.stat(fileName)
  metaDict = {}
  metaDict[fileName] = {}
  metaDict[fileName]['permission'] = {} 
  metaDict[fileName]['permission']['octal']= oct(statInfo.st_mode)[-4:]
  metaDict[fileName]['role'] = {}
  metaDict[fileName]['role']['uid'] = statInfo.st_uid
  metaDict[fileName]['role']['gid'] = statInfo.st_gid
  metaDict[fileName]['content'] = {}
  metaDict[fileName]['content']['length'] = statInfo.st_size
  metaDict[fileName]['content']['hash']= getHash(fileName)
  hashDict['metadata'].update(metaDict)
  return None   

#def fetchMetaData(f,metaType):
#  statInfo = os.stat(f)

'''
if DB_initailize and DB_name and DB_rescan and DIR_names:
  printHelp()
  sys.exit(1)

if DB_initailize and DB_rescan:
  printHelp()
  sys.exit(1)

if DB_initailize and DB_name:
  printHelp()
  sys.exit(1)
'''


if DB_initailize and DB_name and DIR_names:
  creatingHeader() 
  for DIR_Name in DIR_names:
    for  rootDir,subDirs,subFiles in os.walk(DIR_Name):
      for fName in subFiles:
        absPath = os.path.join(rootDir,fName)
        try:
          print('[ Scaning ] : ',absPath)
          metaDictToHashDict(absPath)
          fileObject = open(DB_name,'wb') 
          pickle.dump(hashDict,fileObject)
        except FileNotFoundError:
          pass

if DB_name and DB_rescan:
  fileObject = open(DB_name,'rb') 
  hashDict = pickle.load(fileObject)
  print('')
  print(' [X] READING DATABASE HEADER')
  print('')
  print('  -  Scan Date : ', hashDict['header']['date'])
  print('  -  Directory : ', hashDict['header']['directory'])
  print('')
  print(' [X] READING FILE NAMES')
  print('')
  hashListRescan = hashDict['metadata'].keys()
  print('  -  Total File Found : ', len(hashListRescan))
  print('')
  print(' [X] CHECKING FOR MISSING FILES ')
  print('')
  for  item in hashListRescan:
    if not os.path.exists(item):
      print('  -  :',item)    
  print('')
  print(' [X] CHECKING FOR PERMISSION CHANGES ')
  print('')
  for  item in hashListRescan:
    if  os.path.exists(item):
      curPermission = oct(os.stat(item).st_mode)[-4:]
      oldPermission = hashDict['metadata'][item]['permission']['octal']
      if  curPermission != oldPermission:
        print('  -  :', '[ O:'+oldPermission+'  C:'+curPermission+']' ,item )    

  print('')
  print(' [X] CHECKSUM VARIFICATION OF CONTENT ')
  print('')
  for  item in hashListRescan:
    if  os.path.exists(item):
      curHash = getHash(item)
      oldHash = hashDict['metadata'][item]['content']['hash']
      if  curHash != oldHash:
        print('  -  :', item )   

  print('')
  print(' [X] OWNERSHIP VARIFICATION OF CONTENT ')
  print('')
  for  item in hashListRescan:
    if  os.path.exists(item):
      curOwner = os.stat(item).st_uid
      oldOwner = hashDict['metadata'][item]['role']['uid']
      if  curOwner != oldOwner:
        print('  -  :', item )   

  print('')
  print(' [X] GROUP VARIFICATION OF CONTENT ')
  print('')

  for  item in hashListRescan:
    if  os.path.exists(item):
      curGid = os.stat(item).st_gid
      oldGid = hashDict['metadata'][item]['role']['gid']
      if  curGid != oldGid:
        print('  -  :', item )