Using Python and MD5 to implement the site hanging horse detection program

One, procedure test

# python check_change.py
    Usage: python check_change.py update /home/wwwroot
           python check_change.py check /home/wwwroot
# python check_change.py update /data/www # Generated site md5 value 
# echo ' ' > /data/www/sitemap.html # Test clean file 
# rm -rf /data/www/sitemap.xml # Test delete file 
# python check_change.py check /data/www  # Look for files that have been tampered with 
/data/www/sitemap.xml
/data/www/sitemap.html

#!/usr/bin/env python
import os,sys,subprocess
def update(path):
    f = open(file,'w')
    for root,dirs,files in os.walk(path):
        for name in files:
            line = os.path.join(root, name)
            (stdin,stderr) = subprocess.Popen(['md5sum',line],stdout=subprocess.PIPE).communicate()
            f.write(stdin)
    f.close()
def check(path):
    f = open(file,'r')
    for line in f:
        check_ok = """echo '%s' | md5sum -c > /dev/null 2>&1""" % line
        #print check_ok
        if not subprocess.call(check_ok, shell = True) == 0:
            abnormal = line.split()
            print abnormal[1]
    f.close()
def Usage():
    print '''
    Usage: python %s update /home/wwwroot
           python %s check /home/wwwroot
    ''' % (sys.argv[0],sys.argv[0])
    sys.exit()
if len(sys.argv) != 3:
    Usage()
file = 'file.key'
model = sys.argv[1]
path = sys.argv[2]
if os.path.exists(path) == False:
    print "033[;31mThe directory or file does not exist033[0m"
    sys.exit()
elif model == 'update':
    update(path)
elif model == 'check':
    check(path)
else:
    Usage()